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Cited by 179Multisensory perception and integrationPsychosomatic Disorders and Their TreatmentsVisual perception and processing mechanisms

The Insula Mediates Access to Awareness of Visual Stimuli Presented Synchronously to the Heartbeat

Open access
Salomon, Roy, Ronchi, Roberta, Dönz, Jonathan, Bello-Ruiz, Javier, Herbelin, Bruno, Martet, Remi, Faivre, Nathan, Schaller, Karl +1 more·2016·The Journal of Neuroscience
DOI 10.1523/jneurosci.4262-15.2016PMC PMC6601849
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Abstract

The processing of interoceptive signals in the insular cortex is thought to underlie self-awareness. However, the influence of interoception on visual awareness and the role of the insular cortex in this process remain unclear. Here, we show in a series of experiments that the relative timing of visual stimuli with respect to the heartbeat modulates visual awareness. We used two masking techniques and show that conscious access for visual stimuli synchronous to participants' heartbeat is suppressed compared with the same stimuli presented asynchronously to their heartbeat. Two independent brain imaging experiments using high-resolution fMRI revealed that the insular cortex was sensitive to both visible and invisible cardio–visual stimulation, showing reduced activation for visual stimuli presented synchronously to the heartbeat. Our results show that interoceptive insular processing affects visual awareness, demonstrating the role of the insula in integrating interoceptive and exteroceptive signals and in the processing of conscious signals beyond self-awareness. SIGNIFICANCE STATEMENT There is growing evidence that interoceptive signals conveying information regarding the internal state of the body influence perception and self-awareness. The insular cortex, which receives sensory inputs from both interoceptive and exteroceptive sources, is thought to integrate these multimodal signals. This study shows that cardiac interoceptive signals modulate awareness for visual stimuli such that visual stimuli occurring at the cardiac frequency take longer to access visual awareness and are more difficult to discriminate. Two fMRI experiments show that the insular region is sensitive to this cardio–visual synchrony even when the visual stimuli are rendered invisible through interocular masking. The results indicate a perceptual and neural suppression for visual events coinciding with cardiac interoceptive signals.

AI snapshot

Written from the paper’s full text.

TL;DR

Visual stimuli presented synchronously with the heartbeat had reduced access to visual awareness and lower discrimination accuracy than asynchronous stimuli. High-resolution fMRI showed reduced anterior insula activation for synchronous cardio-visual stimuli, even when rendered invisible by continuous flash suppression.

Key findings

  • In continuous flash suppression, synchronous cardio-visual stimuli took longer to break suppression than asynchronous stimuli: Experiment 1, 3.6 s (SD 1.2) vs 3.4 s (SD 1.05), t(29)=2, p=0.02, Cohen’s d′=0.38; Experiment 2 replicated this, t(14)=3.5, p=0.008, d′=0.65.
  • In visual crowding, accuracy was lower for synchronous stimuli at the smallest center-to-center distance: 56.1 vs 69.4, t(14)=3.93, p=0.0007, d′=1.1; no reaction-time effect was found.
  • Participants were at chance when explicitly judging cardio-visual synchrony: 52.8% ±13.1, t(22)=1.03, n.s., BF=0.22; this accuracy did not correlate with the suppression effect, r=−0.14, p=0.52.
  • fMRI showed weaker anterior insula activation for synchronous than asynchronous stimuli, both when visible, F(1,6)=17.7, p=0.005, and when invisible under CFS, F(1,7)=9.3, p=0.018; control regions ACC, rSTG, and occipital cortex showed no such difference.

Methods

  • Nine experiments: seven psychophysical experiments using CFS, heartbeat awareness, CFS control, visual control, phase-shifted CFS, and visual crowding; 153 right-handed healthy volunteers were recruited and 143 were included in final psychophysical analyses.
  • CFS presented dynamic Mondrian masks to the dominant eye and a yellow octagon target to the other eye; synchronous targets were timed to the QRS complex, while asynchronous targets were at 80% or 120% of the participant’s heartbeat. Crowding used a three-alternative forced-choice letter discrimination task with peripheral flankers.
  • Two high-resolution 7T fMRI experiments used a BVP sensor and event-related design; a heartbeat awareness task localized anterior insula ROIs, and GLM/ROI analyses compared synchronous vs asynchronous conditions, with RETROICOR used to regress out cardiac signal.

Limitations

  • Stated: the authors cannot rule out other interpretations, including anterior insula roles in temporal processing, temporal synchrony, agency, and error monitoring; predictive coding was not directly tested and requires manipulation of prior expectations.
  • Stated: respiration signals were not available and were not regressed from the fMRI data; breaking CFS as a measure of conscious access has been criticized, though the study supplemented it with visual crowding, Bayesian statistics, and full-suppression fMRI.
  • Evident: the fMRI samples were small (8 and 9 participants, with one excluded from each due to motion artifacts >2 mm) and data were analyzed separately in native space rather than transformed to a standardized space, limiting generalizability.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1523/jneurosci.4262-15.2016

Cites

83 of 83 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 56 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    The relative timing of visual stimuli with respect to the heartbeat modulates visual awareness.

    “Here, we show in a series of experiments that the relative timing of visual stimuli with respect to the heartbeat modulates visual awareness.”
    Quote in the paperSubstantial claim
  • Findingown data

    Visual stimuli occurring at the cardiac frequency are more difficult to discriminate than the same stimuli presented asynchronously to the heartbeat.

    “and are more difficult to discriminate.”
    • Also stated in: § Significance Statement · plain
      “and are more difficult to discriminate (visual crowding) than the same stimuli presented asynchronously to the heartbeat.”
    Quote in the paperSubstantial claim
  • Findingown data

    Conscious access for visual stimuli synchronous to participants' heartbeat is suppressed compared with the same stimuli presented asynchronously to their heartbeat.

    “We used two masking techniques and show that conscious access for visual stimuli synchronous to participants' heartbeat is suppressed compared with the same stimuli presented asynchronously to their heartbeat.”
    • Also stated in: § Significance Statement · plain
      “visual stimuli occurring at the cardiac frequency take longer to access visual awareness”
    • Also stated in: § Significance Statement · plain
      “visual targets presented synchronously to the cardiac frequency require more time (CFS)”
    Quote in the paperSubstantial claim
  • Findingown data

    In Experiment 3, participants were at chance for judging cardio-visual synchrony even when the flashing visual stimuli were fully visible (mean 52.8%, t(22)=1.03, n.s., BF=0.22).

    “The results showed that participants were at chance for judging cardio-visual synchrony even when the flashing visual stimuli were fully visible ( ϭ 52.8 ϭ 13.1, t (22) ϭ 1.03, n.s., BF ϭ 0.22), suggesting substantial evidence for the null hypothesis (one-sample t test vs 50% chance value).”
    Quote in the paperSubstantial claim
  • Findingown data

    In fMRI Experiment 9, after regressing out the cardiac signal, the difference between synchronous and asynchronous conditions in the insulae was significant (F(1,7)=6.4, p=0.039).

    “After regressing out the cardiac signal, the difference between synchronous and asynchronous conditions in the insulae was significant (F (1,7) ϭ 6.4, p ϭ 0.039)”
    Quote in the paperSubstantial claim
  • May combine two claims. 19
  • The quote only partly states this claim. 3
  • Classified as probably not a substantial claim. 22

  • May combine two claims.

    Findingown data

    The insular cortex is sensitive to both visible and invisible cardio-visual stimulation, showing reduced activation for visual stimuli presented synchronously to the heartbeat.

    “Two independent brain imaging experiments using high-resolution fMRI revealed that the insular cortex was sensitive to both visible and invisible cardio-visual stimulation, showing reduced activation for visual stimuli presented synchronously to the heartbeat.”
    • Also stated in: § Significance Statement · plain
      “Two fMRI experiments show that the insular region is sensitive to this cardio-visual synchrony even when the visual stimuli are rendered invisible through interocular masking.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In fMRI Experiment 9, the effect was robust and stable in 14 of the 15 present fMRI participants, showing lower BOLD activity in the synchronous condition in the right anterior insula.

    “Importantly, this effect was robust and stable in 14 of the 15 present fMRI participants, showing lower BOLD activity in the synchronous condition in the right anterior insula.”
    Quote in the paperSubstantial claim

  • The quote only partly states this claim.

    Findingown data

    In Experiment 5, when visual stimuli were decoupled from heartbeat, no differences between stimuli that were 'synchronous' or 'asynchronous' to the heartbeat in Experiment 2 were found (t(14)=1.2, p=0.12, BF=0.5).

    “Furthermore, when decoupled (Experiment 5), no differences between visual stimuli that were”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Findingown data

    The anterior cingulate cortex (ACC), right posterior superior temporal gyrus (rSTG), and occipital visual regions were consistently activated and were selected as ROIs for each subject (at p < 0.001 FDR).

    “The anterior cingulate cortex (ACC), right posterior superior temporal gyrus (rSTG), and occipital visual regions were consistently activated and were selected as ROIs for each subject (at p Ͻ 0.001 FDR).”
    Quote in the paperSubstantial claim

  • The quote only partly states this claim.

    Findingown data

    In fMRI Experiment 8, insula activation was weaker during synchronous than asynchronous cardio-visual stimulation (F(1,6)=17.7, p=0.005; after RETROICOR F(1,6)=18.4, p=0.005).

    “Estimating the mean BOLD signal response in the left and right anterior insulae (as defined above) for the synchronous and asynchronous cardio-visual conditions, we found that insula activation was weaker during synchronous than asynchronous cardio-visual stimulation (F (1,6) ϭ 17.7, p ϭ 0.005), compatible with suppression of visually induced activation in the insula depending on cardio-visual”
    • Also stated in: § Neural suppression of seen synchronous cardio-visual stimuli: fMRI · plain
      “The difference between the BOLD activity in the anterior insulae between synchronous and asynchronous conditions was significant (F (1,6) ϭ 18.4, p ϭ 0.005), with no difference between the left and right insulae (F (1,6) ϭ 1.3, n.s.).”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    The processing of interoceptive signals in the insular cortex is thought to underlie self-awareness.

    “Another line of work has linked self-awareness to the processing of interoceptive signals in the insular cortex (i.e., cardiac signals; Damasio, 2000;Craig, 2002;Critchley et al., 2004;Park et al., 2014)”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Damasio, 2000

      Not checked in the free run.

    • cites Craig, 2002

      Not checked in the free run.

    • cites Critchley et al., 2004

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    To ensure that trial onset did not maintain a specific phase in relation to participants' heartbeat, an intertrial interval of 0.5, 0.8, or 1.3 s was presented between trials such that any spurious temporal relation between cardiac and visual stimuli would not be maintained.

    “To ensure that trial onset did not maintain a specific phase in relation to participants' heartbeat, an intertrial interval of 0.5, 0.8, or 1.3 s was presented between trials such that any spurious temporal relation between cardiac and visual stimuli would not be maintained.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductnone given

    The target type, center-to-center distance between target and flanker, and cardio-visual synchronicity were fully randomized.

    “The target type, center-to-center distance between target and flanker, and cardio-visual synchronicity were fully randomized.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Predictive models of interoception mediate widespread sensory consequences of interoceptive signals such as cardiac activity, thus reducing their influence on perception.

    “These predictive models of interoception are held to mediate widespread sensory consequences of interoceptive signals such as cardiac activity (Barrett and Simmons, 2015), thus reducing their influence on perception (comparable to suppression of retinal changes due to ocular motion).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Barrett and Simmons, 2015

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data

    The BVP sensor on the fingertip is delayed by ~250 ms compared with the ECG R-wave, but the frequency detected by BVP and ECG systems is identical.

    “Pilot testing indicated that the BVP on the fingertip was delayed by ϳ250 ms compared with the ECG R-wave, but that the frequency detected by the BVP and ECG systems was identical (also see Lu et al., 2009).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Lu et al., 2009

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S4 (based). May combine two claims.

    Premisenone given

    The influence of interoception on visual awareness and the role of the insular cortex in this process remain unclear.

    “However, the influence of interoception on visual awareness and the role of the insular cortex in this process remain unclear.”
    • Also stated in: § Significance Statement · plain
      “their role in other forms of awareness such as visual awareness is yet unclear.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    The insula may be involved in interoceptive inference in which predictions regarding interoceptive signals are compared with actual sensory and interoceptive afferent inputs.

    “Recently, theories have suggested that the insula may be involved in interoceptive inference in which predictions regarding interoceptive signals are compared with actual sensory and interoceptive afferent inputs (Critchley and Seth, 2012;Seth, 2013;Apps and Tsakiris, 2014).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Critchley and Seth, 2012

      Not checked in the free run.

    • cites Seth, 2013

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    • cites Apps and Tsakiris, 2014

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Participants were explicitly asked not to monitor their heartbeat by means other than interoceptive attention (such as taking their pulse).

    “The participants were explicitly asked not to monitor their heartbeat by means other than interoceptive attention (such as taking their pulse).”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Study design and conductnone given

    A 1 s intertrial interval was used to avoid intertrial phase locking.

    “A 1 s intertrial interval was used to avoid intertrial phase locking.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    The echo-planar images acquired during the functional runs were corrected for low frequencies (e.g., due to cardiac and breathing artifacts) and 3D motion and were then transformed to the native space of the anatomical run.

    “The echo-planar images acquired during the functional runs were corrected for low frequencies (e.g., due to cardiac and breathing artifacts) and 3D motion and were then transformed to the native space of the anatomical run.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim. May combine two claims.

    Study design and conductreasoning

    The naivety of the subjects to the relationship between the flashing target and their heartbeat was important to avoid recording any brain activity resulting from interoceptive attention to their heartbeat; therefore, this relationship was not mentioned before this task.

    “The naivety of the subjects to this relationship was important to avoid recording any brain activity resulting from interoceptive attention to their heartbeat; therefore, this relationship was not mentioned before this task.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Using the BVP signal, the six cardiac specific regressors created by the RETROICOR toolbox were used as control covariates in the design matrix.

    “Using the BVP signal, the six cardiac specific regressors created by the RETROICOR toolbox were used used as control covariates in our design matrix.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). The quote only partly states this claim.

    Study design and conductown data

    Ten participants were excluded from the analysis across the first seven experiments.

    “Ten participants were excluded from the analysis (Experiment 1, n ϭ 1; Experiment 2, n ϭ 3; Experiment 4, n ϭ 3; Experiment 5, n ϭ 2; Experiment 7, n ϭ 1).”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The second task served as a functional localizer for the anterior insula regions, which have been shown previously to be activated by interoceptive attention to one's heartbeat.

    “This second task served as a functional localizer for the anterior insula regions, which have been shown previously to be activated by interoceptive attention to one's heartbeat (Critchley et al., 2004;Wiebking et al., 2014).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Critchley et al., 2004

      Not checked in the free run.

    • cites Wiebking et al., 2014

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductcitation

    To test for possible effects of cardiac activity on the results, the cardiac signal was regressed out using the RETROICOR approach.

    “To test for possible effects of cardiac activity on the results, the cardiac signal was regressed out using the RETROICOR approach (Glover et al., 2000).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Glover et al., 2000

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    Cardio-visual effects on CFS in Experiments 1 and 2 depend on cardio-visual coupling and not on visual differences between synchronous and asynchronous visual stimulation.

    “This indicates that cardio-visual effects on CFS (Experiments 1 and 2) depend on cardio-visual coupling and not on visual differences between synchronous and asynchronous visual stimulation.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    The insular cortex is a prime candidate region responsible for suppressing cardio-visual signals because it is involved in interoceptive processing including cardiac signals, in comparison of auditory and cardiac signals, and has been hypothesized as a site for multimodal integration and sensory prediction related to the self.

    “A prime candidate region responsible for suppressing such signals is the insular cortex because of the following: (1) it is involved in the processing of interoceptive information including cardiac signals (Craig, 2002;Critchley et al., 2004), (2) it is involved in the the comparison of auditory and cardiac signals (Critchley et al., 2004), and (3) it has recently been hypothesized as a site for”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Craig, 2002

      Not checked in the free run.

    • cites Critchley et al., 2004

      Not checked in the free run.

    • cites Critchley and Seth, 2012

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    The results in the anterior insulae are independent of vascular fluctuations and are more likely to reflect neuron-related BOLD changes.

    “This suggests that the results in the anterior insulae are independent of vascular fluctuations and are more likely to reflect neuron-related BOLD changes.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    In fMRI Experiment 8, the task was always performed before the localizer task to ensure that participants were naive to the purpose of the experiment.

    “This task was always performed before the localizer task to ensure that participants were naive to the purpose of Experiment 8.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Study design and conductown data

    In fMRI Experiment 9, analysis was restricted to trials in which participants were fully unaware of the visual stimuli (78.6% of trials).

    “We restricted our analysis to trials in which the participants were fully unaware of the visual stimuli (78.6% of trials).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductown data

    Because respiration signals were not available, they were not regressed from the functional data.

    “Because respiration signals were not available, they were not regressed from the functional data.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The heartbeat affects tactile afferent output, muscle spindle discharge, and generates mechanical effects on the eyes modulating interocular pressure and eye movements.

    “For example, the heartbeat affects tactile afferent output (Macefield, 2003), muscle spindle discharge (Birznieks et al., 2012), and generates mechanical effects on the eyes modulating interocular pressure and eye movements (de Kinkelder et al., 2011).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Macefield, 2003

      Not checked in the free run.

    • cites Birznieks et al., 2012

      Not checked in the free run.

    • cites de Kinkelder et al., 2011

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Previous investigations have shown cardiac effects on somatosensory, nociceptive, and emotional processing.

    “Previous investigations of cardiac influences on behavior and neural processing have focused on specific epochs of the cardiac cycle (e.g., systole vs diastole) and have been successful in showing cardiac effects on somatosensory (Edwards et al., 2009;Gray et al., 2009), nociceptive (Edwards et al., 2001;McIntyre et al., 2006;Edwards et al., 2008;Gray et al., 2010), and emotional (Gray et al., 200”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Edwards et al., 2009

      Not checked in the free run.

    • cites Gray et al., 2009

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    • cites Garfinkel et al., 2014

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    The results suggest a possible role of the insula for multimodal predictive coding and salience processing.

    “These results converge in suggesting the possible role of the insula for multimodal predictive coding (Singer et al., 2009;Seth et al., 2011;Apps and Tsakiris, 2014) and salience processing (Seeley et al., 2007).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Singer et al., 2009

      Not checked in the free run.

    • cites Seth et al., 2011

      Not checked in the free run.

    • cites Seeley et al., 2007

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Premisecitation

    The anterior insula has been implicated in temporal processing and activated in studies investigating temporal synchrony, sense of agency, and error monitoring.

    “The anterior insula has been implicated in temporal processing (Craig, 2009a;Wiener et al., 2010), which has been suggested to relate to its role in integrating internal interoceptive temporal cues with external signals (Wittmann, 2009;Wittmann et al., 2010).”
    • Also stated in: § Discussion · plain
      “Indeed, the anterior insula has been activated in studies investigating temporal synchrony (Bushara et al., 2001) and the sense of agency and error monitoring that require matching exteroceptive sensory signals with self-generated actions (Menon et al., 2001;Klein et al., 2007;Karnath and Baier, 2010;Sperduti et al., 2011;Klein et al., 2013).”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites Craig, 2009a

      Not checked in the free run.

    • cites Bushara et al., 2001 source

      Not checked in the free run.

    • cites Menon et al., 2001

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Interoceptive information regarding cardiac activity is conveyed by several afferent sources, including cardiac and somatosensory mechanoreceptors as well as blood vessel baroreceptors.

    “Interoceptive information regarding cardiac activity is conveyed by several afferent sources, including cardiac and somatosensory mechanoreceptors as well as blood vessel baroreceptors (Knapp and Brener, 1998), and is affected by several cardiac factors (Schandry et al., 1993).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Knapp and Brener, 1998

      Not checked in the free run.

    • cites Schandry et al., 1993

      Not checked in the free run.

  • May combine two claims.

    Study design and conductown data

    In the current study, the breaking CFS paradigms were supplemented with visual crowding (Experiment 7), which allowed replication of the finding in the accuracy domain and circumvented possible limitations of time-to-emergence measures used with CFS.

    “In the current study, however, the breaking CFS paradigms were supplemented with an additional psychophysical method of visual crowding (Experiment 7), which allowed us to replicate our finding in the accuracy domain, thus circumventing the possible limitations of time to emergence used with the CFS method.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The insular cortex is activated by a wide range of perceptual and cognitive processes.

    “The insular cortex has been found to be activated by a wide range of perceptual and cognitive processes (Kurth et al., 2010).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Kurth et al., 2010

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    The insular cortex is thought to enable the convergence of interoceptive and exteroceptive signals and has been proposed to underlie self-awareness and exteroceptive multisensory bodily perception and movement control.

    “This region is thought to enable the convergence of interoceptive and exteroceptive signals (Craig, 2002;Critchley et al., 2004;Wiebking et al., 2014) and has recently also been proposed to underlie self-awareness (Damasio, 2000;Craig, 2009b;Craig, 2010;Apps and Tsakiris, 2014) and exteroceptive multisensory bodily perception and movement control in healthy and neurological patients (Karnath et al”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Craig, 2002

      Not checked in the free run.

    • cites Critchley et al., 2004

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    • cites Karnath et al., 2005

      Not checked in the free run.

34 of 34

  • The paper relies on this without support.

    The heartbeat is a lifelong and critical signal for the organism that must be monitored continuously and kept within tight limits to avoid arrhythmia or asystolia, and this monitoring normally occurs outside awareness because one does not experience control over one's heart.

    “The heartbeat is a lifelong and critical signal for the organism, which must be monitored continuously and kept within tight limits to avoid, for example, arrhythmia or asystolia; such monitoring, in most instances, occurs outside of awareness because one does not experience control over one's heart.”

  • The paper relies on this without support.

    The frequency of cardiac-related effects is identical across all afferent inputs.

    “In contrast, the frequency of cardiac-related effects is identical across all afferent inputs.”

  • The paper relies on this without support.

    The sensory consequences of the heartbeat differ in their temporal delay as a function of the distance from the heart.

    “Although the heartbeat is a periodic signal, its sensory consequences differ in their temporal delay as a function of the distance from the heart.”
3 of 3

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?

  • Interoceptive signalling shapes experiences of self and perceptions of stimuli originating from the external environment.

    “Accumulating clinical data and experimental evidence are revealing the mechanisms by which interoceptive signalling shapes experiences of self, and also of perceptions of stimuli originating from the external environment (e.g. [94,95]).”

    From Active interoceptive inference and the emotional brain (2016) · cites this paper as [94]

  • Processing of auditory or visual stimuli is attenuated when synchronized with the heartbeat.

    “and the processing of either auditory 39 or visual 40 stimuli attenuated when synchronized with the heartbeat.”

    From Interoceptive rhythms in the brain (2023) · cites this paper as [40]

  • Bodily self-consciousness impacts several perceptual and cognitive functions such as tactile perception, pain perception, visual perception, and egocentric cognitive processes.

    “Recent findings have shown that BSC impacts several perceptual and cognitive functions such as tactile perception [48,49], pain perception [50,51], visual perception [52–54], as well as egocentric cognitive processes [55].”

    From First-person view of one’s body in immersive virtual reality: Influence on episodic memory (2019) · cites this paper as [54]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

  • Experiment 9 trial epochs total 22 seconds, not 24

    Minor

    The stated fixation, stimulus, two response, and rest epochs add to 22 seconds. The trial duration is reported as 24 seconds, leaving 2 seconds unaccounted for.

    Reported 24 · recomputed 22

  • Returning participants are counted as new volunteers

    Minor

    The seven experiment counts sum to 153 participations, but the 23 participants in Experiment 3 had already participated in Experiment 1. The counts therefore describe 130 distinct volunteers, not 153.

    Reported 153 · recomputed 130

  • Experiment 9 voxel width conflicts with matrix and field of view

    Minor

    A 210 mm field of view divided into 160 matrix elements gives an in-plane voxel width of 1.3125 mm, not the reported 1.8 mm.

    Reported 1.8 · recomputed 1.3125

3 of 3

Cites

Flagged first, then by citations

Research works printed but not linked: 1

  1. Knapp, 1998, Mechanoreceptors responsible for transducing heartbeat sensations, Psychophysiology, 35, S51

Cited by

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Related

Authors
Salomon, R., Ronchi, R., Dönz, J., Bello-Ruiz, J., Herbelin, B., Martet, R., Faivre, N., Schaller, K., & Blanke, O.
Affiliations
  • École Polytechnique Fédérale de Lausanne (CH)
  • University Hospital of Geneva (CH)
ORCID
Venue
The Journal of Neuroscience
Publisher
Society for Neuroscience
Published
2016-05-04
Volume
36
Issue
18
Pages
5115-5127
ISSN
  • 0270-6474 (ISSN-L)
  • 1529-2401
DOI
10.1523/jneurosci.4262-15.2016
PMC
PMC6601849
OpenAlex
W2347134072
Cited by
178
References
83
Citations by year
2026: 11 · 2025: 16 · 2024: 16 · 2023: 16 · 2022: 23 · 2021: 21 · 2020: 12 · 2019: 20 · 2018: 18 · 2017: 15 · 2016: 10
FWCI
29.81
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Neuroscience (publishedVersion, cc-by-nc-sa)
  • Europe PMC (PubMed Central) (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Archive ouverte UNIGE (University of Geneva) (publishedVersion)
  • HAL (submittedVersion, other-oa)
  • Infoscience (Ecole Polytechnique Fédérale de Lausanne) (submittedVersion)
  • Infoscience (Ecole Polytechnique Fédérale de Lausanne) (submittedVersion, cc-by-nc-nd)
  • Archive ouverte UNIGE (University of Geneva) (submittedVersion, cc-by)
Funders
  • National Science Foundation
  • Fondation Bertarelli
  • European Commission
  • European Science Foundation
  • Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (125759)
Topics
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Multisensory perception and integration
  • Health Sciences › Medicine › Psychiatry and Mental health › Psychosomatic Disorders and Their Treatments
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Visual perception and processing mechanisms
Keywords
insula, interoception, visual awareness, interoceptive awareness, conscious access, heart rate, self-awareness
MeSH terms
Adolescent, Adult, Awareness, Brain Mapping, Cerebral Cortex, Female, Heart, Humans, Image Processing, Computer-Assisted, Magnetic Resonance Imaging, Male, Perceptual Masking, Photic Stimulation, Visual Perception, Young Adult, Interoception

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.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-09.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-09.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

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