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Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise
Open accessAbstract
The hippocampus has been shown to demonstrate a remarkable degree of plasticity in response to a variety of tasks and experiences. For example, the size of the human hippocampus has been shown to increase in response to aerobic exercise. However, it is currently unknown what underlies these changes. Here we scanned sedentary, young to middle-aged human adults before and after a six-week exercise intervention using nine different neuroimaging measures of brain structure, vasculature, and diffusion. We then tested two different hypotheses regarding the nature of the underlying changes in the tissue. Surprisingly, we found no evidence of a vascular change as has been previously reported. Rather, the pattern of changes is better explained by an increase in myelination. Finally, we show that hippocampal volume increase is temporary, returning to baseline after an additional six weeks without aerobic exercise. This is the first demonstration of a change in hippocampal volume in early to middle adulthood suggesting that hippocampal volume is modulated by aerobic exercise throughout the lifespan rather than only in the presence of age related atrophy. It is also the first demonstration of hippocampal volume change over a period of only six weeks, suggesting that gross morphometric hippocampal plasticity occurs faster than previously thought.
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TL;DR
In sedentary young-to-middle-aged adults, six weeks of supervised aerobic exercise increased anterior hippocampal volume, but this increase returned to baseline after six further weeks without exercise. Multimodal MRI measures did not support a vascular change; the pattern was better explained by increased myelination.
Key findings
- Six weeks of aerobic exercise significantly changed anterior hippocampal volume (LME log likelihood ratio = 6.95, P = 0.0084), with volume increased immediately post-training; at six weeks post-training, volume was not statistically different from baseline (log likelihood ratio = 0.38, P = 0.54).
- Fitness improved with exercise (V̇O2 max model log likelihood ratio = 13.25, P < 0.001), but was not significantly elevated six weeks after training ended (log likelihood ratio = 0.01, P = 0.92).
- The vascular-change hypothesis was not supported by combined multimodal measures (Stouffer’s Z = −1.05, P = 0.78), whereas the myelination-change hypothesis was supported (Z = 2.64, P = 0.01).
- No significant changes were observed in any cognitive task, and thalamus volume showed no significant exercise effect (log likelihood ratio = 0.0007, P = 0.98).
Methods
- 62 sedentary adults (35 women, 27 men; mean age 33.7, SD 11.9) were studied; 54 were pseudo-randomly assigned in a crossover design to “rest first” or “exercise first,” and 8 were baseline-only. Exercise consisted of 30 minutes of supervised stationary cycling, 5 days/week for 6 weeks; average attendance was 29.05 of 30 sessions (SD 1.05).
- MRI at 3T included T1, T2, QSM, SWI, CBV, diffusion measures (MD, FA), and gray/white matter segmentation. FreeSurfer hippocampal subfield segmentation was used to define the anterior-most 25% of the hippocampus in native space.
- Longitudinal linear mixed effects models tested exercise effects over time, and a non-parametric permutation-based Stouffer’s method combined multimodal Z-scores to test vascular versus myelin hypotheses.
Limitations
- Stated: the lack of cognitive changes may reflect the short intervention, choice of cognitive tests, or participant age; T1 measurement may have been noisy or affected by opposing biological changes; other microstructural changes such as neuronal density, dendritic spines, or synaptogenesis were not tested; the intervention may have been too short to elicit vascular effects; and non-exercise features such as social interaction or novel environment could have contributed.
- Stated: hippocampal head segmentation used a quartering strategy because distinguishing head, body, and tail with 3T MRI is difficult.
- Evident: dropout reduced the completers available for longitudinal analysis (25 exercise-first and 15 rest-first completed all three scans), and the baseline-only group received only a single scan.
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30 Not checked yet · 23 Own result · 13 Own method · 6 Own interpretation · 1 Sources not found · 1 No basis given
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In the paper
“This model provided a significantly better fit for the variance in V̇O2 max than the baseline model which included only subject ID and time (log likelihood ratio=13.25, P < 0.001), suggesting that exercise caused significant change in fitness.”
- Also stated in: § 3.2. Exercise training improves fitness but does not not change cognitive scores · plain
“Inspection of the time course of change in V̇O2 max (Figure 2 and Table 1) reveals that fitness is increased immediately post training.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.2. Exercise training improves fitness but does not not change cognitive scores
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- Also stated in: § 3.2. Exercise training improves fitness but does not not change cognitive scores · plain
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In the paper
“Thalamus volume showed no significant effects of exercise (Log Likelihood Ratio=0.0007, P=0.98).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.3. Anterior Hippocampal Volume Increase
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“Thus, V̇O2 max is not statistically different from baseline at the twelve-week visit, six weeks after the end of the exercise training program.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.2. Exercise training improves fitness but does not not change cognitive scores
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In the paper
“while the myelin change hypothesis was significant (Z=2.64, P=0.01).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.4. Exploratory multimodal measurements of change within anterior hippocampus
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“No significant correlations were found between cognitive scores and fitness after accounting for age, sex, and total brain volume and correcting for multiple comparisons.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.1. Baseline correlations between fitness, hippocampal volume, and cognitive
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In the paper
“In this study we have provided the first demonstration that volume increase in the anterior hippocampus occurs in early to middle adulthood after just six weeks of aerobic exercise.”
- Also stated in: § 4. Discussion · boosted
“This study therefore provides novel evidence that just six weeks of exercise results in increases in hippocampal volume in young to middle aged adults.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“another measure that has been used to measure myelin, the T1/T2 ratio (Glasser and Van Essen, 2011), did show an increase in the anterior hippocampus (Z = 1.54).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“This increase is not permanent, returning to baseline after six further weeks without regular aerobic exercise.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“Testing the vascular change hypothesis failed to reach significance on the Stouffer’s test (Z=−1.05, P=0.78)”
- Also stated in: § Abstract · plain
“we found no evidence of a vascular change as has been previously reported.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.4. Exploratory multimodal measurements of change within anterior hippocampus
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- Also stated in: § Abstract · plain
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In the paper
“No significant changes with exercise were observed in any of the cognitive tasks.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.2. Exercise training improves fitness but does not not change cognitive scores
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“changes in WM, T1, T2, QSM, CBV, and SWI are not consistent with an increase in vasculature as might be predicted by the existing literature.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
hedged- Asserted: passes — The authors put it forward as true.
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- Rests on an assumption: Vascular and myelin changes modulate MR properties in predictable ways.
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In the paper
“We were unable to replicate this result in our study even when our CBV analysis was restricted to the dentate gyrus region of the hippocampus.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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“we did not find significant changes in any cognitive measure after exercise.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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“We also found no correlation between motion parameters and anterior hippocampus volume or total gray matter volume (P > 0.47).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“we evaluated the motion parameters from our DTI sequence and found no evidence of a difference in absolute or relative subject motion before and after exercise (P > 0.15).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“the majority of our imaging measures supported an increase in myelination within anterior hippocampus”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“the lack of an increase in T1 is a surprising and notable exception”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“we found no evidence of an increase in vasculature in the anterior hippocampus.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“While our study had more participants completing the exercise intervention (41 vs. 11)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“The apparent transient nature of the myelin increase also suggests that continuing an active lifestyle may be important for maintaining improvement in brain structure.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
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In the paper
“However, there is little evidence on the effects of exercise on the brain in early to middle adulthood, despite clear relevance of this question to lifelong cognitive health (Voelcker-Rehage and Niemann, 2013).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 1. Introduction
What the sources say
- Not checked yetcites Voelcker-Rehage and Niemann, 2013
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In the paper
“As previous studies have shown that hippocampal plasticity tends to be focused in the anterior head portion (Erickson et al., 2011; Sagi et al., 2012), we focused our analysis on the anterior quarter of the hippocampus.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 2. Materials and Methods > 2.3. Imaging methods
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In the paper
“Rather, the pattern of changes is better explained by an increase in myelination.”
- Also stated in: § 3.4. Exploratory multimodal measurements of change within anterior hippocampus · hedged
“It is apparent from this graph that WM, T2, and QSM are all showing relatively large shifts consistent with a myelination change, while T1 and CBV show little change at all (Figure 4).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > Abstract
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In the paper
“Rather, the pattern of changes are better explained by an increase in myelin.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
plaindirect- Asserted: passes — The authors put it forward as true.
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- Rests on an assumption: Vascular and myelin changes modulate MR properties in predictable ways.
None of the sources cited for this claim have been checked yet.
In the paper
“CBV is a direct measure of blood volume (Wenz et al., 1996; Lu et al., 2005; Barbier et al., 2001)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.4. Exploratory multimodal measurements of change within anterior hippocampus
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In the paper
“SWI images show lower intensity in highly vascularized regions (Haacke et al., 2004)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.4. Exploratory multimodal measurements of change within anterior hippocampus
What the sources say
- Not checked yetcites Haacke et al., 2004 source
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In the paper
“T2 is similarly significantly higher in vasculature than in myelin-rich regions (Stanisz et al., 2005; Wansapura et al., 1999)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.4. Exploratory multimodal measurements of change within anterior hippocampus
What the sources say
boosted- Asserted: passes — The authors put it forward as true.
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In the paper
“We found no correlation between this interval and the change in anterior-hippocampal volume (R=−0.07, P=0.64).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.3. Anterior Hippocampal Volume Increase
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In the paper
“These and other studies have shown that myelination changes can occur in a time frame much less than the six-week intervention used here (Yeung et al., 2014; Gibson et al., 2014).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“its sensitivity to subtle changes in spatial ability is limited by the fact that the scoring technique is relatively coarse and that healthy subjects often perform near ceiling.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“The method we used to quantify T1 has been recently criticized as suffering from inaccuracies due to RF field inhomogeneities (Lankford and Does, 2013; Stikov et al., 2014).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“Previous studies have shown longitudinal change in performance on a spatial memory task in older adults that correlates with change in hippocampal volume after a year-long exercise intervention (Erickson et al., 2011).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Erickson et al., 2011 source
plaincorrelational- Asserted: passes — The authors put it forward as true.
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In the paper
“this study has provided important insight into the time course and mechanism of exercise-mediated plasticity in the anterior hippocampus”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
plaindirect- Asserted: passes — The authors put it forward as true.
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In the paper
“there are also a considerable number of myelinated fibers within hippocampal grey matter (Benes et al., 1994).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Benes et al., 1994 source
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“the intervention in Pereira et al. (2007) is twice as long (3 months vs. 6 weeks).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Pereira et al., 2007 source
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In the paper
“interventions in most prior longitudinal studies have been six to twelve months in duration (Erickson et al., 2011)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Erickson et al., 2011 source
plain- Asserted: passes — The authors put it forward as true.
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In the paper
“A previous human study by Pereira et al. (2007) reported a significant increase in CBV specifically in the dentate gyrus region of the hippocampus after three months of regular aerobic exercise in a group of eleven healthy adults.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Pereira et al., 2007 source
plaindirectn = 11- Asserted: passes — The authors put it forward as true.
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- It may state two separate claims as one. 19
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In the paper
“A similar pattern was observed for the whole hippocampus however the effect was not significant (Log Likelihood Ratio=1.31, P=0.25).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.3. Anterior Hippocampal Volume Increase
plain- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This variable provided no significant additional power to the model (Log Likelihood Ratio=0.38, P=0.54), suggesting that six weeks after the completion of the exercise training program, anterior hippocampal volume was not statistically different from baseline.”
- Also stated in: § Abstract · plain
“we show hippocampal volume increase is temporary, returning to baseline after an additional six weeks without aerobic exercise.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.3. Anterior Hippocampal Volume Increase
plain- Asserted: passes — The authors put it forward as true.
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It may state two separate claims as one.
- Also stated in: § Abstract · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This model provided a significantly better fit for the anterior hippocampal volume as compared to a model containing just subject ID and time (Log Likelihood Ratio=6.95, P=0.0084), demonstrating that the exercise intervention significantly changed anterior hippocampal volume.”
- Also stated in: § 3.3. Anterior Hippocampal Volume Increase · plain
“Inspection of the time course of volume change (Figure 3 and S2) reveals that hippocampal volume is increased immediately post-training.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.3. Anterior Hippocampal Volume Increase
boosteddirect- Asserted: passes — The authors put it forward as true.
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The quote only partly states this claim.
- Also stated in: § 3.3. Anterior Hippocampal Volume Increase · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“It is apparent from this graph that WM, T2, and QSM are all showing relatively large shifts consistent with a myelination change, while T1 and CBV show little change at all (Figure 4).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.4. Exploratory multimodal measurements of change within anterior hippocampus
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Out of thirty possible aerobic exercise training sessions, the average attendance was 29.05 sessions (SD 1.05).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.2. Exercise training improves fitness but does not not change cognitive scores
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
None of the sources cited for this claim have been checked yet.
In the paper
“Habitual aerobic exercise has been widely associated with greater cognitive performance in older adults as well as adolescents (Kramer and Erickson, 2007; Anderson-Hanley et al., 2012; Benedict et al., 2012; Aberg et al., 2009; Young et al., 2015).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 1. Introduction
What the sources say
boostedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“A recent longitudinal study has demonstrated that one year of aerobic exercise has a direct causal role in increasing the volume of the hippocampus in sedentary older adults (Erickson et al., 2011).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 1. Introduction
What the sources say
- Not checked yetcites Erickson et al., 2011 source
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
None of the sources cited for this claim have been checked yet.
In the paper
“Environmental enrichment, a less specific manipulation, has been shown to increase myelination of callosal fibres (Markham et al., 2009; Zhao et al., 2012).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 1. Introduction
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Measures of cardiovascular fitness have been shown to increase after as little as one week of exercise training (Hickson et al., 1981).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 1. Introduction
What the sources say
- Not checked yetcites Hickson et al., 1981 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Each volume was visually inspected for segmentation errors. No manual correction was required.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 2. Materials and Methods > 2.3. Imaging methods
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
In the paper
“Longitudinal LME modelling has been demonstrated to be a be superior technique to more common alternatives such as repeated measure ANOVA or simple paired T-test in that it provides more statistical power and is robust in the face of missing data (Bernal-Rusiel et al., 2013).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 2. Materials and Methods > 2.4. Statistical analyses
What the sources say
- Not checked yetcites Bernal-Rusiel et al., 2013 source
boosted- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“QSM has been shown to be dark in myelin-rich regions and bright in blood-rich regions (Deistung et al., 2013; Stuber and Turner, 2010)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.4. Exploratory multimodal measurements of change within anterior hippocampus
What the sources say
- Not checked yetcites Deistung et al., 2013 source
- Not checked yetcites Stuber and Turner, 2010
boostedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Using a standard crossover design, 54 of the 62 participants were pseudo-randomly assigned to one of two groups: “rest first” or “exercise first” (Figure 1).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 2. Materials and Methods > 2.1. Participants and experimental design
plainn = 62- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“The permutation method randomly flips the signs of each subject’s data, but does so synchronously over subjects to preserve the dependence.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 2. Materials and Methods > 2.4. Statistical analyses
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“It is also the first demonstration of hippocampal volume change over a period of only six weeks, suggesting gross morphometric hippocampal plasticity occurs faster than previously thought.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > Abstract
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“At baseline, we found no significant differences between the exercise-first and rest-first groups in fitness, anterior hippocampal volume or cognitive scores.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.1. Baseline correlations between fitness, hippocampal volume, and cognitive
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“For example, it has been shown that aerobic exercise increases the rate of neurogenesis in the dentate gyrus region of the rodent hippocampus and increases cerebral blood volume (CBV) in the same region in humans (Pereira et al., 2007; van Praag et al., 1999a,b).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 1. Introduction
What the sources say
- Not checked yetcites Pereira et al., 2007 source
- Not checked yetcites van Praag et al., 1999a,b
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This is the first demonstration of a change in hippocampal volume in early to middle adulthood suggesting that hippocampal volume is modulated by aerobic exercise throughout the lifespan rather than only in the presence of age related atrophy.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > Abstract
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“The T1 of blood is high whereas that of myelin is low, compared to average T1 in gray matter (Stanisz et al., 2005; Wansapura et al., 1999)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 3. Results > 3.4. Exploratory multimodal measurements of change within anterior hippocampus
What the sources say
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Note that no correction for intracranial volume was necessary as our analysis only explored differences within subject.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 2. Materials and Methods > 2.3. Imaging methods
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Histological examination of the hippocampus reveals three obvious subdivision along the longitudinal axis: the head, the body, and the tail (Duvernoy, 2005; Strange et al., 2014), with the body being somewhat longer than the other two segments.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Duvernoy, 2005
- Not checked yetcites Strange et al., 2014 source
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
In the paper
“In the hippocampus, exercise alone leads to increased production of new neurons while exercise paired with environmental enrichment leads to greater survival of new neurons (van Praag et al., 2000, 2005).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not matchedcites van Praag et al., 2000, 2005
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Not matched
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“These approaches remove the possibility of spurious results due to biased alignments, properly model both between and within subject sources of variance, and control for potential time-related confounds such as scanner drift and practice.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“previously published studies in rodents that have shown a robust vascular change within the hippocampus after a prolonged period of exercise (Pereira et al., 2007; Van der Borght et al., 2009; van Praag et al., 2005).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
boosteddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
None of the sources cited for this claim have been checked yet.
In the paper
“Although a number of studies have reported change in brain volumes with exercise interventions in older adults (Erickson et al., 2011; Anderson-Hanley et al., 2012)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
In the paper
“it has been recently demonstrated that an increase in head motion could result in artifactual changes in segmented volumes (Reuter et al., 2014).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Reuter et al., 2014
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Similarly, in cerebellum, exercise alone has been shown to increase capillary density while exercise paired with environmental enrichment leads to an increase in synaptic density (Black et al., 1990).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Black et al., 1990 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“It is difficult to address this dichotomy in a human study, as the daily lives of humans are constantly enriched compared to that of a rodent housed in a laboratory setting.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
- Rests on an assumption: Human daily lives are constantly enriched compared to laboratory rodents.
In the paper
“Growth of mossy fibers in the rat hippocampus with physical exercise has been previously reported (Toscano-Silva et al., 2010), however these fibers are not myelinated.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Toscano-Silva et al., 2010 source
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“many investigators consider R1 (1/T1) to be the best MR measure of myelin content (Stüber et al., 2014; Lutti et al., 2013).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“We have also used well established Linear Mixed Effects models for statistical inference.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
boosted- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
None of the sources cited for this claim have been checked yet.
In the paper
“Neuronal activity-dependent changes in myelination have been observed in cell culture (Wake et al., 2011; Fields, 2010) as well as in recent in vivo experiments (Gibson et al., 2014).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
plaincorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
In the paper
“Previous studies have shown volume changes in the entire hippocampus which appeared to be driven by the anterior half of the structure (Erickson et al., 2011).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Erickson et al., 2011 source
hedgeddirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The apparent transient nature of the myelin increase also suggests that continuing an active lifestyle may be important for maintaining improvement in brain structure.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“We cannot rule out the possibility that these or other micro-structural changes, that we have not tested here, could also contribute.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
hedged- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Histology also requires fixation which, depending on the precise procedure used, can cause shrinkage and dehydration, potentially distorting volume measurements (Overgaard and Meden, 2000).”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
What the sources say
- Not checked yetcites Overgaard and Meden, 2000
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“we cannot rule out the possibility that other features of the intervention, such as social interaction and experience of a novel environment, could contribute to the effects we observed.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
hedgedconditional- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: fails — The paper’s conclusions may not depend on it.
- Based: passes — The paper gives a reason why it holds.
Probably not a substantial claim. The paper’s conclusions may not depend on it.
The authors state this as an assumption.
For the longitudinal LME models, the baseline expectation was that measures change linearly over time.
“For all of our LME analyses, a linear change with time was used as the null hypothesis.”
The paper relies on this without support.
During the six-week rest phase, rest-first participants kept their usual physical activity levels.
“Participants in the rest first group were then asked to maintain their normal level of physical activity for six weeks, after which they returned for a second cognitive and fitness assessment and MRI scan.”
The paper relies on this without support.
After training, exercise-first participants resumed their usual activity levels.
“At the end of the exercise program they were scanned and assessed again, and allowed to return to their normal level of activity.”
The paper relies on this without support.
The study sample is representative of sedentary young to middle-aged adults for generalizing the effects of aerobic exercise on hippocampal volume.
“We tested a total of 62 sedentary adult subjects (35 women and 27 males, mean age 33.7, S.D. 11.9).”
The paper relies on this without support.
Effects of exercise on brain volumes in young to middle-aged adults have not been well studied.
“effects in young to middle aged adults have not been well studied.”
The paper relies on this without support.
Distinguishing the hippocampal head, body, and tail with 3T MRI is difficult.
“Distinguishing these three segments with 3T MRI images is difficult”
The paper relies on this without support.
Vascular and myelin changes have been shown to occur after exercise or neuronal activity.
“These two types of change were chosen as they have been shown to occur after exercise or neuronal activity”
The paper relies on this without support.
Vascular and myelin changes modulate MR properties in predictable ways.
“and also because they modulate MR properties in predictable ways.”
The paper relies on this without support.
Other micro-structural changes such as neuronal density, dendritic spines, or synaptogenesis are not known to produce predictable changes in MR properties.
“We did not test for other changes such as neuronal density, dendritic spines, or synaptogenesis as these micro-structural changes are not known to produce predictable changes in MR properties.”
The paper relies on this without support.
Histology samples only a small portion of a region, whereas imaging averages signal across the entire region.
“the disadvantage of histology is that only a small portion of a given region is sampled, whereas imaging allows the signal to be averaged across the entire region of issue.”
The paper relies on this without support.
Human daily lives are constantly enriched compared to laboratory rodents.
“the daily lives of humans are constantly enriched compared to that of a rodent housed in a laboratory setting.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
In the citing paper
“while regular exercise for > 3 months can effectively reshape the central nervous system organization of patients with depression [80].”
From Systematic review and meta-analysis of the effects of exercise on depression in adolescents (2022) · cites this paper as [80]
In the citing paper
“RCTs in healthy samples have demonstrated that AE interventions were associated with increases in hippocampal volume in young and middle aged (Thomas et al., 2016) and older adults (Colcombe et al., 2006; Erickson et al., 2011; Niemann et al., 2014; Kleemeyer et al., 2015; Maass et al., 2015; Sexton et al., 2015a).”
From Aerobic Exercise as a Tool to Improve Hippocampal Plasticity and Function in Humans: Practical Implications for Mental Health Treatment (2016) · cites this paper as Thomas et al., 2016
Statistics recomputed
Every reported test result, recomputed from its test statistic and degrees of freedom. A result shows as not adding up only once an independent check has confirmed it.
- Consistentz = -1.05reported p = .78 · recomputed p = .294
“(Z=−1.05, p = .78”
The paper states an exact test
- Consistentz = 2.64reported p = .01 · recomputed p = .008
“(Z=2.64, p = .01”
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
“A total of 151 scans were acquired.”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 2. Materials and Methods > 2.1. Participants and experimental design
Reported 151 · recomputed 154
Rated minor: it would not touch a result — a value no result rests on, a p-value that stays on the same side of the significance level, or a conflict that is clerical, resolved elsewhere in the paper, or outside its own findings.
In the paper
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 4. Discussion
“our study had more participants completing the exercise intervention (41 vs. 11)”
§ Multi-modal characterization of rapid anterior hippocampal volume increase associated with aerobic exercise > 2. Materials and Methods > 2.1. Participants and experimental design
“four dropped out after two scans (pre- and post-training), and 25 completed all three scans. Twenty-four participants were assigned to the rest first condition. In this group, one participant dropped out after the fist scan, eight dropped out after two scans, and fifteen completed all three scans.”
Citations
Cites
R: A Language and Environment for Statistical Computing
R Core Team (2000) · doi:10.32614/r.manuals · Cited by 355,893
The CES-D Scale: A Self-Report Depression Scale for Research in the General Population
Radloff, L. S. (1977) · Applied Psychological Measurement · doi:10.1177/014662167700100306 · Cited by 53,267
nlme : Linear and nonlinear mixed effects models
DebRoy, S. (2006) · Medical Entomology and Zoology · Cited by 10,009
Zhang, Y., Brady, M., & Smith, S. M. (2001) · IEEE Transactions on Medical Imaging · doi:10.1109/42.906424 · Cited by 7,628 · cited 2×
“and white matter segmentations were performed using FMRIB’s Automated Segmentation Tool (FAST) (Zhang et al., 2001) without smoothing.”
Methodnlme: Linear and Nonlinear Mixed Effects Models
Pinheiro, J., R Core Team, & Bates, D. (1999) · doi:10.32614/cran.package.nlme · Cited by 6,867
Exercise training increases size of hippocampus and improves memory
Erickson, K. I., Voss, M. W., Prakash, R. S., Basak, C., Szabo, A., Chaddock, L., Kim, J. S., Heo, S., Alves, H., White, S. M., et al. (2011) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1015950108 · Cited by 4,855 · cited 6×
“A recent longitudinal study has demonstrated that one year of aerobic exercise has a direct causal role in increasing the volume of the hippocampus in sedentary older adults (Erickson et al., 2011).”
BackgroundInfluentialPerceived exertion as an indicator of somatic stress
Borg, G. (1970) · Journal of Rehabilitation Medicine · doi:10.2340/1650197719702239298 · Cited by 4,723 · cited 1×
“Rating of Perceived Exertion (RPE) was also monitored (Borg, 1970).”
MethodFitzmaurice, G. M., Laird, N. M., & Ware, J. H. (2011) · Wiley Series in Probability and Statistics · doi:10.1002/9781119513469 · Cited by 4,639 · cited 2×
“The first is that LME separately and effectively models variance due to within and between subject factors (Fitzmaurice et al., 2011; Verbeke and Molenberghs, 2009).”
BackgroundRunning increases cell proliferation and neurogenesis in the adult mouse dentate gyrus
van Praag, H., Kempermann, G., & Gage, F. H. (1999) · Nature Neuroscience · doi:10.1038/6368 · Cited by 3,880
Age-predicted maximal heart rate revisited
Tanaka, H., Monahan, K. D., & Seals, D. R. (2001) · Journal of the American College of Cardiology · doi:10.1016/s0735-1097(00)01054-8 · Cited by 3,775 · cited 1×
“…estimated V ̇ O 2 max was calculated by performing a linear fit between Heart Rate (HR) and V ̇ O 2 scores during the test and projecting the V ̇ O 2 value at the participant’s age-predicted heart rate maximum (208 − 0.7 * Age, Tanaka et al., 2001; American College of Sports Medicine, 2006).”
MethodInfluential
Cited by
Sorted by citations
Kandola, A., Ashdown-Franks, G., Hendrikse, J., Sabiston, C. M., & Stubbs, B. (2019) · Neuroscience & Biobehavioral Reviews · doi:10.1016/j.neubiorev.2019.09.040 · Cited by 1,309
Effect of aerobic exercise on hippocampal volume in humans: A systematic review and meta-analysis
Firth, J., Stubbs, B., Vancampfort, D., Schuch, F., Lagopoulos, J., Rosenbaum, S., & Ward, P. B. (2018) · NeuroImage · doi:10.1016/j.neuroimage.2017.11.007 · Cited by 526
“examining the effects of exercise in young-to-middle-aged adults found no change in total hippocampal volume but did find a significant increase in anterior hippocampal volume following 6 weeks of aerobic exercise (Thomas et al., 2016).”
InfluentialTopiwala, A., Allan, C. L., Valkanova, V., Zsoldos, E., Filippini, N., Sexton, C., Mahmood, A., Fooks, P., Singh-Manoux, A., Mackay, C. E., et al. (2017) · BMJ · doi:10.1136/bmj.j2353 · Cited by 455
White Matter Plasticity in the Adult Brain
Sampaio‐Baptista, C., & Johansen‐Berg, H. (2017) · Neuron · doi:10.1016/j.neuron.2017.11.026 · Cited by 432
“…has been extensively reported to have an impact on gray matter volume of the hippocampus as measured by neuroimaging (Erickson et al., 2011; Thomas et al., 2016), but the underlying cellular drivers for gross changes following exercise interventions detected using neuroimaging remain…”
BackgroundResultSelf-citationEffects of Exercise on Brain and Cognition Across Age Groups and Health States
Stillman, C. M., Esteban‐Cornejo, I., Brown, B. M., Bender, C. M., & Erickson, K. I. (2020) · Trends in Neurosciences · doi:10.1016/j.tins.2020.04.010 · Cited by 444
Metadata
- Authors
- Thomas, A. G., Dennis, A., Rawlings, N. B., Stagg, C. J., Matthews, L., Morris, M., Kolind, S. H., Foxley, S., Jenkinson, M., Nichols, T. E., Dawes, H., Bandettini, P. A., & Johansen-Berg, H.
- Affiliations
- National Institutes of Health (US)
- University of Oxford (GB)
- Oxford Brookes University (GB)
- King's College London (GB)
- University of Warwick (GB)
- Corresponding author
- Thomas, Adam G.
- ORCID
- Venue
- NeuroImage
- Publisher
- Elsevier BV
- Published
- 2016-05
- Volume
- 131
- Pages
- 162-170
- ISSN
- 1053-8119 (ISSN-L)
- PMC
- PMC4848119
- OpenAlex
- W2184267685
- Cited by
- 152
- References
- 93
- Citations by year
- 2026: 10 · 2025: 13 · 2024: 11 · 2023: 10 · 2022: 13 · 2021: 20 · 2020: 23 · 2019: 16 · 2018: 13 · 2017: 14 · 2016: 9
- FWCI
- 4.87
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- NeuroImage (publishedVersion)
- PubMed (publishedVersion)
- PubMed Central (acceptedVersion)
- Pure (Coventry University) (submittedVersion, cc-by-nc-nd)
- Funders
- NIMH
- UK National Institutes of Health Research (NIHR) Oxford Biomedical Research Centre
- Topics
- Life Sciences › Neuroscience › Developmental Neuroscience › Neurogenesis and neuroplasticity mechanisms
- Life Sciences › Neuroscience › Cognitive Neuroscience › Memory and Neural Mechanisms
- Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Advanced Neuroimaging Techniques and Applications
- Keywords
- hippocampal volume, aerobic exercise, hippocampal plasticity, myelination, neurovascular changes, diffusion MRI, brain structure, exercise intervention, midlife, hippocampal atrophy, neuroimaging
- MeSH terms
- Adult, Aging, Blood Flow Velocity, Cerebrovascular Circulation, Female, Hippocampus, Humans, Male, Neuronal Plasticity, Organ Size, Exercise, Neuroimaging, Physical Conditioning, Human, Multimodal Imaging
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
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