Principles derived from the study of simple skills do not generalize to complex skill learning

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

Lower levels of action identity refer to details of the action, while higher levels relate to effects of the action.

“Lower levels in an action's identity structure refer to the details of the action, such as the specific movements (e.g., striking the correct keys on a piano), whereas higher levels are more related to the effects of the action (e.g., playing the melody).”

• cites Vallacher & Wegner, 1985Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Vallacher & Wegner, 1987 sourceSupported

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

Vallacher and Wegner's action identification theory proposes a hierarchical order of action identities used in control of action.

“In their action identification theory, Vallacher and Wegner proposed a hierarchical order of action identities that are used in the control of action.”

• cites Vallacher & Wegner, 1985Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Vallacher & Wegner, 1987 sourceSupported

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

If a performer selects too low a level of action control, performance is often disrupted.

“If the performer selects too low a level of action control-for example, because of pressure to perform well-performance is often disrupted.”

• cites Vallacher & Wegner, 1985Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Vallacher & Wegner, 1987 sourcePartly supported

  The Performance Impairment section (p. 7) says that controlling an easy or familiar action at too low a level can disrupt it. It does not say disruption occurs often; it also describes pressure to perform well as emphasizing higher-level meanings, rather than as an example of selecting too low a level. (LLM, conf=0.85)

  Experimental — accuracy not yet measured

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

If lower and higher levels of action identity are available, higher level identities become prepotent.

“They argued that if lower and higher levels of action identity are available, higher level identities become prepotent.”

• cites Vallacher & Wegner, 1985Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Vallacher & Wegner, 1987 sourceSupported

May combine two claims.

Random practice is usually more effective than blocked practice for learning simple skills with low memory demands and/or for experienced participants; for complex skills with high memory and processing demands, blocked practice might be more effective, at least early in learning.

“random practice is usu-ally more effective than blocked practice when it comes to the learning of simple skills, for which the memory demands are relatively low, and/or when participants are experienced to the extent that they have functionally reduced the demands on memory”

• Also stated in: § Contextual Interference · hedged

  “For the learning of more complex skills for which memory and processing demands are high, blocked practice might be more effective, at least early in the learning process.”

Not yet classified.

Introducing additional demands during complex skill learning may be detrimental because the additional demands compete with essential processing activities for a limited amount of processing capacity.

“It is conceivable that introducing additional demands for the learner during this process is actually detrimental, rather than beneficial, because the additional demands compete with the essential processing activities for a limited amount of processing capacity during the learning process.”

• AssumptionRests on an assumption: Learners have a limited amount of processing capacity.

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

J. B. Shea and Morgan first demonstrated the contextual interference effect for motor skill learning.

“J. B. Shea and Morgan (1979) were the first to demonstrate the CI effect for motor skill learning.”

• cites J. B. Shea & Morgan, 1979 sourceNot checked — no full text of the source

May combine two claims.

Functional task complexity changes as a result of expertise, and as an individual develops expertise with a task, the functional complexity of the task decreases.

“functional task complexity changes as a result of expertise.”

• Also stated in: § THEORETICAL AND REVIEW ARTICLES · plain

  “as an individual performer develops expertise with a task, the functional complexity of the task decreases.”

• cites Adams, 1976 sourceNot checked — no full text of the source
• cites Schneider & Shiffrin, 1977 sourceNot checked — no full text of the source

Not yet classified.

Smith and Davies found benefits of high contextual interference practice for learning the Pawlata kayak roll, and Wrisberg and colleagues found that alternating different serves produced more effective learning than blocked practice.

“One study that found benefits of high-CI practice for the learning of a sport skill is a study by Smith and Davies (1995), who used the Pawlata kayak roll.”

• Also stated in: § Contextual Interference

  “Wrisberg and colleagues (Wrisberg, 1991;Wrisberg & Liu, 1991) have found additional convincing evidence for the greater effectiveness of practice conditions that included frequent changes between tasks.In both studies, alternating different serves produced more effective learning than did blocked practice.”

• cites Smith & Davies, 1995 sourceNot checked — no full text of the source
• cites Wrisberg, 1991Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Wrisberg & Liu, 1991 sourceNot checked — no full text of the source

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

A random practice order exercises retrieval processes that later facilitate test performance and requires more effort than blocked practice, so performance at test is usually enhanced.

“because a random practice order of different tasks exercises retrieval processes that later facilitate test performanceand therefore requires more effort than does blocked practice-performance at the time of the test is usually enhanced”

• cites Magill & Hall, 1990 sourceNot checked — no full text of the source

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

The learning advantages of random over blocked practice have been replicated in numerous laboratory experiments since J. B. Shea and Morgan.

“Since the J. B. Shea and Morgan (1979) study, the learning advantages of random, as compared with blocked, practice have been replicated in numerous laboratory experiments.”

• cites J. B. Shea & Morgan, 1979 sourceNot checked — no full text of the source

May combine two claims.

In situations with low processing demands, practice conditions that increase load and challenge the performer benefit learning; in situations with extremely high load, conditions that reduce load to manageable levels benefit learning.

“situations with low processing demands benefit from practice conditions that increase the load and challenge the performer, whereas practice conditions that result in extremely high load should benefit from conditions that reduce the load to more manageable levels.”

Not yet classified.

Complex skill learning might be enhanced by providing practice conditions that facilitate performance until a relatively stable movement representation is acquired.

“complex skill learning might be enhanced by providing the learner with practice conditions that facilitate performance (at least until a relatively stable movement presentation is acquired).”

May combine two claims.

For relatively simple skills, a rough movement representation may be developed within a few practice trials, and further refinement of the skill depends on the extent to which the learner is challenged by practice conditions.

“For relatively simple skills, a rough movement representation may be developed within a few practice trials, and it is easy to see that a further refinement of the skill is dependent on the extent to which the learner is challenged by the practice conditions.”

May combine two claims.

The tasks used to examine effects of variables on motor learning have generally been relatively simple, often involving one degree of freedom, requiring small amounts of practice to reach asymptotes, and placing modest demands on attention, memory, and processing.

“In general, however, the tasks used to examine the effects of these variables on learning have been relatively simpleoften including only one degree of freedom, requiring comparatively small amounts of practice to reach performance asymptotes, and placing relatively modest demands on attention,memory, and/or processing capacity.”

Not yet classified.

Making augmented feedback difficult to use, for example by delaying it or withholding it on some practice trials, is beneficial for test performance because it forces learners to develop their own internal error-correction and error-detection mechanisms.

“making augmented feedback difficult to use-for example, by delaying it or by withholdingit on some practice trials-has been argued to be beneficial for test performance because it forces learners to develop their own internal error-correction-and-detection mechanisms”

• cites Schmidt, 1991a sourceNot checked — no full text of the source

Classified as probably not a substantial claim.

Practice conditions that promote additional cognitive effort or require additional information-processing activities critical for test performance are most effective for learning simple skills.

“practice conditions that promote additional cognitive effort (Lee, Swinnen, & Serrien, 1994) or require the learner to engage in additionalinformation-processing activities that are critical for test performance (Schmidt & Bjork, 1992) are most effective for learning.”

• cites Lee, Swinnen, & Serrien, 1994 sourceNot checked — no full text of the source
• cites Schmidt & Bjork, 1992 sourceNot checked — no full text of the source

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

Complex skills may be sensitive to variables that are not particularly relevant for simple skills.

“it is also possible that complex skills are sensitive to variables that are not particularly relevant for simple skills.”

Not yet classified.

The contextual interference effect has been demonstrated fairly consistently for relatively simple laboratory tasks, but this does not seem to be the case for more complex skills.

“whereas the CI effect has been demonstrated fairly consistently for relatively simple laboratory tasks, this does not seem to be the case for more complex skills.”

Not yet classified.

Delaying feedback for a few seconds produces more effective learning than giving feedback immediately after or concurrently with the movement.

“delaying the feedback for a few seconds has been found to produce more effective learning than does giving feedback immediately after or even concurrently with the movement”

• cites Schmidt & Wulf, 1997 sourceNot checked — no full text of the source
• cites Swinnen, Schmidt, Nicholson, & Shapiro, 1990 sourceNot checked — no full text of the source
• cites Vander Linden, Cauraugh, & Greene, 1993 sourceNot checked — no full text of the source

Not yet classified.

Recent experiments consistently found relative timing advantages for constant and blocked practice relative to serial and random practice, directly opposite the typical contextual interference effect.

“a number of recent experiments (e.g., Lai & Shea, 1998, 1999;Lai, Shea, Wulf, & Wright, 2000;C. H. Shea, Lai, Wright, Immink, & Black, 2001;Whitacre & Shea, 2000) consistently found relative timing advantages for constant and blocked practice, relative to serial and random practice, directly opposite the typical CI effect.”

• cites Lai & Shea, 1998, 1999Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Lai, Shea, Wulf, & Wright, 2000 sourceNot checked — no full text of the source
• cites C. H. Shea, Lai, Wright, Immink, & Black, 2001 sourceNot checked — no full text of the source

May combine two claims.

In animal conditioning, partial reinforcement slows acquisition but maintains learning for much longer than continuous reinforcement does.

“partial reinforcement has been shown to slow acquisition but also to maintain learning for much longer than continuous reinforcement does.”

• cites Tarpy, 1982Not checked — no full text of the source

May combine two claims.

Wright, Li, and Whitacre found that additional processing disrupted learning under random-practice conditions but had positive effects under blocked conditions.

“Wright, Li, and Whitacre (1992; also see Lee, Wishart, Cunningham, & Carnahan, 1997) found that additional processing disrupted learning under random-practice conditions but had positive effects under blocked conditions.”

• cites Wright, Li, & Whitacre, 1992 sourceNot checked — no full text of the source

May combine two claims.

Beneficial learning effects of reduced feedback in humans are seen not only in no-feedback retention tests but also in 100% feedback retention tests, which argues against the extinction explanation.

“one set of findings that argues against such an explanation for human learning is that beneficial learning effects of reduced feedback are seen not only in no-feedback retention tests, but also in 100% feedback retention tests.”

• cites Winstein & Schmidt, 1990 sourceNot checked — no full text of the source
• cites Wulf & Schmidt, 1989 sourceNot checked — no full text of the source

May combine two claims.

Contrary to simple tasks in which reducing relative feedback frequency is more beneficial, learning of the more complex ski simulator task was enhanced by 100% feedback.

“Thus, contrary to studies that used more simple tasks in which reducing the relative feedback frequency was more beneficial for learning than was providing learners with feedback after or during every practice trial (e.g., Schmidt & Wulf, 1997;Winstein & Schmidt, 1990;Wulf & Schmidt, 1989;Wulf et al., 1993), the learning of this more complex task was enhanced by 100% feedback.”

• cites Schmidt & Wulf, 1997 sourceNot checked — no full text of the source
• cites Winstein & Schmidt, 1990 sourceNot checked — no full text of the source
• cites Wulf & Schmidt, 1989 sourceNot checked — no full text of the source

• AssumptionRests on an assumption: The simple and complex tasks compared across the reviewed studies are sufficiently comparable that differences in findings can be attributed to task complexity rather than to other methodological differences.

May combine two claims.

In that study, only the 100% feedback group was significantly more effective than the control group, while the 50% group did not differ significantly from either group.

“Furthermore, only the 100% group was significantly more effective than the control group, whereas the 50% group did not differ significantly from either group.”

• cites Wulf, Shea, & Matschiner (1998) sourceNot checked — no full text of the source

May combine two claims.

For a more complex simulated batting task, the optimal number of summary trials was lower than for simpler tasks, with a 5-trial summary being more beneficial than 15-trial or 1-trial summaries.

“Schmidt, Lange, and Young (1990) showed that the optimal number of summary trials for a more complex simulated batting task was lower than those found for more simple tasks.In this case, a summary of 5 trials was more beneficial than longer (15) or shorter (1) feedback summaries.”

• cites Schmidt, Lange, and Young (1990) sourceNot checked — no full text of the source

Not yet classified.

The principles underlying animal reinforcement and feedback in humans have some similarities but also important differences.

“This suggests that although the principles underlying animal reinforcement and feedback in humans have some similarities, they show some important differences as well.”

Not yet classified.

The advantage of 100% feedback occurred even though the feedback was continuous and concurrent.

“Interestingly, this advantage occurred even though the feedback given in the Wulf, Shea, and Matschiner (1998) study was continuous and concurrent.”

• cites Wulf, Shea, and Matschiner (1998) sourceNot checked — no full text of the source

May combine two claims.

Complex tasks requiring considerably more memory capacity per task may exceed the performer's capacity, especially early in practice when a single complex task may initially be stored as a series of subcomponents.

“complex tasks, presumably requiring considerably more memory capacity per task, may exceed the capacity of the performer.This may be especially true early in practice, where a single complex task may be initially stored as a series of subcomponents”

• cites Povel & Collard, 1982 sourceNot checked — no full text of the source

Not yet classified.

Learning of simple skills tends to improve when augmented feedback is reduced or delayed, although this effect is stronger under variable practice conditions.

“Although the learning of simple skills seems to benefit from reducing or delaying the augmented feedback (although this effect appears to be stronger for variable practice conditions; see Lai & Shea, 1998)”

• cites Lai & Shea, 1998 sourceNot checked — no full text of the source

May combine two claims.

In the ski simulator study, during delayed retention the 100% feedback group improved across trials, the 50% feedback group showed no gains, and the control group showed a performance decrement.

“However, the group that had received the most feedback (100%) during practice showed a clear performance improvement across trials, whereas the 50% feedback group showed no such performance gains, and the control group even demonstrated a performance decrement.”

• cites Wulf, Shea, & Matschiner (1998) sourceNot checked — no full text of the source

May combine two claims.

Long feedback summaries benefited learning of a relatively simple striking task for both novices and experienced participants, and benefited a more complex double-striking task for experienced participants, but single-trial feedback was more effective than longer summaries for novices learning a complex task.

“whereas relatively long feedback summaries benefited the learning of a relatively simple striking task for both novice and experienced participants, as well as the learning of a more complex double-striking task for experienced participants, single-trial feedback was more effective than longer feedback summaries for novices trying to learn a complex task.”

• cites Guadagnoli et al. (1996) sourceNot checked — no full text of the source

May combine two claims.

The 100% feedback group developed a more effective error-detection-and-correction mechanism than the 50% and no-feedback conditions, enabling further performance improvements without feedback.

“Rather, it seems that the participants in the 100% feedback group developed a more effective error-detection-and-correction mechanism (e.g., Salmoni et al., 1984;Schmidt, 1991a), as compared with the 50% feedback and no-feedback (control) conditions, which enabled them to demonstrate further performance improvements even in the absence of feedback.”

• cites Salmoni et al., 1984 sourceNot checked — no full text of the source
• cites Schmidt, 1991a sourceNot checked — no full text of the source

May combine two claims.

Immediate reinforcement is more effective than delayed reinforcement in animal learning, but this is not the case for skill learning in humans.

“immediate reinforcement is more effective than delayed reinforcement in animal learning, but this is not the case for skill learning in humans.”

May combine two claims.

In that experiment, the beneficial effects of blocked practice appeared in amplitude, while there were no significant group differences in force onset.

“In this experiment, the beneficial effects of blocked practice were seen in amplitude, whereas there were no significant group differences in force onset (even though feedback was given about force onset, as in Wulf & Bühner, 1996)”

• cites Wulf, Hörger, and Shea (1999) sourceNot checked — no full text of the source

May combine two claims.

Concurrent feedback typically has strong performance-enhancing effects during practice but results in clear performance decrements relative to postresponse feedback when it is withdrawn in retention or transfer tests.

“concurrent feedback typically has strong performance-enhancing effects during practice, but results in clear performance decrements, relative to postresponse feedback, when it is withdrawn in retention or transfer tests”

• cites Schmidt & Wulf, 1997 sourceNot checked — no full text of the source
• cites Vander Linden et al., 1993 sourceNot checked — no full text of the source
• cites Winstein et al., 1996 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

Observational practice seems to have clear benefits for more complex skills.

“it seems to have clear benefits for more complex skills.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

A number of studies have demonstrated that the performer's focus of attention can have a decisive influence on performance and learning.

“A number of studies have demonstrated that the performer's focus of attention can have a decisive influence on performance and learning.”

Not yet classified.

The negative effects thought to be associated with the guidance provided by frequent feedback appear to be reduced in complex tasks.

“That is, the negative effects thought to be associated with the guidance provided by frequent feedback seem to be reduced.”

May combine two claims.

For complex movements with many degrees of freedom, there may be advantages to using physical assistance procedures, supporting the view that complex skill learning benefits from reducing demands on the learner.

“For complex movements with many degrees of freedom, such as those encountered in many sports situations, there might actually be advantages to using physical assistance procedures, corroborating the view that complex skill learning benefits from reducing the demands imposed on the learner.”

• AssumptionRests on an assumption: The simple and complex tasks compared across the reviewed studies are sufficiently comparable that differences in findings can be attributed to task complexity rather than to other methodological differences.
• AssumptionRests on an assumption: Task complexity is a well-defined property that distinguishes simple laboratory tasks from complex motor skills.

May combine two claims.

The benefits in force onset provided by the poles during practice were not only temporary; they transferred to a no-pole situation and were relatively permanent, meaning the poles enhanced learning of a more efficient movement pattern relative to practice without poles.

“Thus, the benefits in force onset provided by the poles during practice were not only temporary effects.Rather, these benefits transferred to a situation in which no poles could be used, and they were relatively permanent in nature; that is, the poles enhanced the learning of a more efficient movement pattern, relative to practice without poles.”

Classified as probably not a substantial claim.

Some principles or phenomena relevant to complex skill learning may be less powerful or may not appear in simple laboratory tasks.

“some principles or phenomena that could be relevant for the learning of complex skills might be less powerful or might not show up in tasks such as those typically used in the laboratory.”

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

Physical assistance may be conducive to learning to the extent that it allows the learner to explore the perceptual-motor workspace.

“It is conceivable that physical assistance is conducive to learning to the extent that it allows the learner to explore the”

• cites Newell, 1991 sourceNot checked — no full text of the source

May combine two claims.

In Wulf and Weigelt's ski simulator experiment, instructions to delay forcing the platform until after the center did not enhance learning and were detrimental to practice and stress transfer relative to no instructions.

“Wulf and Weigelt found that the instructions did not enhance the learning of this task; rather, they were detrimental to performance during practice and transfer to a”

• cites Wulf & Weigelt, 1997 sourceNot checked — no full text of the source

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

A characteristic of complex motor skills that is difficult to simulate with simple tasks is that the performer can direct attention to various aspects of the task.

“One characteristic of complex motor skills that is difficult to simulate with simple tasks is that the performer can direct his or her attention to various aspects of the task.”

May combine two claims.

On the ski simulator, the poles may have enabled learners to experience that shifting weight from the outer to the inner foot relatively late is more effective; this experience shortened the learning process and allowed learners to reach a given performance level in less time.

“On the ski simulator, the poles might have enabled learners to experience (consciouslyor unconsciously) that it is more effective to shift the weight from the outer to the inner foot relatively late-that is, to delay the force onset of the inner foot.This experience provided by the poles served to shorten the learning process and enabled the learners to reach a given level of performance in less”

May combine two claims.

In Wulf, Höß, and Prinz (1998, Experiment 1), external focus on wheels was more effective for producing large movement amplitudes than internal focus on feet in both practice and retention, and internal focus was not different from control.

“The results indicated that the latter condition was much more effective for the production of large movement amplitudes than was the internal focus condition in both practice and retention, which was not different from a control condition without additional instructions”

• cites Wulf, Höß, & Prinz, 1998 sourceNot checked — no full text of the source

Classified as probably not a substantial claim.

Todorov, Shadmehr, and Bizzi (1997) argued that the highest level of motor planning and control is in terms of kinematics of the end-effector, so feedback should be most effective if it represents end-effector movements rather than body movements.

“Todorov et al. argued that the highest level of motor planning and control seems to be in terms of the kinematics of the endeffector and that, therefore, the feedback given to the learner should be most effective if it represents the movements of the end-effector, rather than the body movements.”

• cites Todorov, Shadmehr, & Bizzi, 1997 sourceNot checked — no full text of the source

May combine two claims. The quote only partly states this claim.

In Wulf, Shea, and Park (2001), a considerably greater number of participants chose external focus on markers (n=16) rather than internal focus on feet (n=4); those choosing markers were clearly more effective in retention than those focusing on feet.

“A considerably greater number of participants chose to focus on the markers that were located in front of their feet (n = 16), rather than on the feet themselves (n = 4).”

• cites Wulf, Shea, & Park, 2001 sourceNot checked — no full text of the source

Not yet classified.

Feedback in complex tasks is generally less prescriptive than in many simple tasks, because complex tasks often require coordination of different components, making it difficult for a single feedback measure to be truly prescriptive.

“It should also be noted, however, that feedback in complex tasks is generally not as prescriptive as it often is in many of the simple tasks that have been used in this context.In complex tasks, there are often different components that have to be coordinated to produce skilled performance, making it much more difficult for a single feedback measure to be truly prescriptive.”

May combine two claims.

The advantage in movement outcome was not accomplished at the expense of movement form; expert ratings showed both feedback types led to similar improvements in form.

“Furthermore, this advantage in the movement outcome was not accomplished at the expense of movement form.As was determined through expert ratings, both types of feedback led to similar improvements in form.”

• cites Wulf et al., in pressNot matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Not yet classified.

These results suggest that there may be limits to the generalizability of findings from studies using typical laboratory tasks with few degrees of freedom.

“These results again suggest that there may be limitations to the generalizabilityof findings from studies using typical laboratory tasks with few degrees of freedom.”

• AssumptionRests on an assumption: The simple and complex tasks compared across the reviewed studies are sufficiently comparable that differences in findings can be attributed to task complexity rather than to other methodological differences.
• AssumptionRests on an assumption: Task complexity is a well-defined property that distinguishes simple laboratory tasks from complex motor skills.

May combine two claims.

The benefits of physical guidance appear to be mainly temporary: guidance often enhances performance during practice, but when it is withdrawn in retention or transfer tests, performance is often less effective than that of learners who practiced without or with less guidance.

“As Schmidt (1988Schmidt ( , 1991b;;Schmidt & Wrisberg, 2000) points out, the benefits of (physical) guidance seem to be mainly temporary in nature.Guidance often has strong performance-enhancing effects during practice, when it is present; yet when it is withdrawn in retention or transfer tests, performance is often less effective than that of learners who practiced the task without or with less”

• cites Schmidt, 1988Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Schmidt, 1991bNot matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Schmidt & Wrisberg, 2000Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Not yet classified.

In Wulf, Höß, and Prinz's second experiment, stabilometer learning was enhanced by external focus (markers) relative to internal focus (feet).

“In that experiment, the learning of the stabilometer task was also enhanced by an external focus of attention (markers attached to the board in front of each foot), relative to an internal attentional focus (feet).”

• cites Wulf, Höß, & Prinz, 1998 sourceNot checked — no full text of the source

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

When poles were removed in retention, the pole group showed no performance decrements in amplitude or force onset; both groups had similar amplitudes in delayed retention, and the pole group showed superior learning in relative force onset.

“More important, though, when the poles were removed in retention, the group that had practiced with the poles showed no performance decrements in amplitude or force onset.Both groups had very similar amplitudes in the delayed retention test, and even more interesting, the pole group demonstrated superior learning with regard to relative force onset.”

• cites Wulf, Shea, & Whitacre (1998) sourceNot checked — no full text of the source

May combine two claims.

Learning of simple tasks may be enhanced by making practice more difficult or challenging, such as by reducing feedback frequency or providing serial/random feedback, whereas learning of complex skills may not benefit and may even be degraded by increasing demands on the learner.

“Together, these results suggest that whereas the learning of simple tasks might be enhanced by making practice more”

• AssumptionRests on an assumption: The simple and complex tasks compared across the reviewed studies are sufficiently comparable that differences in findings can be attributed to task complexity rather than to other methodological differences.
• AssumptionRests on an assumption: Task complexity is a well-defined property that distinguishes simple laboratory tasks from complex motor skills.

May combine two claims.

In C. H. Shea and Wulf (1999), learning was more effective with external-focus instructions than internal-focus instructions, and with external relative to internal feedback, even though feedback display was identical.

“The results demonstrated that learning was more effective not only when performers were given external-focus instructions, relative to internal-focus instructions, but also when they were provided”

• cites C. H. Shea & Wulf, 1999Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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

In Wulf, Lauterbach, and Toole (1999), external-focus instructions on club head motion greatly enhanced golf pitch shot accuracy in practice and delayed retention compared with internal-focus instructions on arm swing.

“Here again, the external-focus instructions greatly enhanced the accuracy of the shots in practice and in delayed retention, as compared with the internal-focus instructions.”

• cites Wulf, Lauterbach, & Toole, 1999 sourceNot checked — no full text of the source

May combine two claims.

In Singer, Lidor, and Cauraugh (1993), nonawareness strategy and five-step approach focusing on a situational cue resulted in more effective practice performance and immediate dual-task transfer than an awareness strategy focusing on own movements; awareness group was no more effective than control.

“They found that a nonawareness strategy and the so-called fivestep approach, in which performers were instructed to focus on a situational cue (e.g., the center of the target), resulted in more effective practice performance and (immediate) dual-task transfer than did an awareness strategy, in which learners were to focus on their own movements.”

• cites Singer, Lidor, & Cauraugh, 1993 sourceNot checked — no full text of the source

May combine two claims.

In novices, movement form was degraded by internal-focus feedback during practice, but this group caught up with the external-focus group in retention without feedback.

“although the movement form in the novice group was degraded by internalfocus feedback during practice, this group caught up with the external-focus group in the retention test, where the feedback was withdrawn.”

• cites Wulf et al., in pressNot matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

These findings suggest that feedback can induce an external focus of attention, independent of attentional focus instructions, that benefits performance and learning.

“these findings seem to suggest that feedback can have the capacity to induce an external focus of attention, independent of attentional focus instructions, that benefits performance and learning.”

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

Withdrawal of feedback in retention had no detrimental effect on performance.

“It is also interesting to note that the withdrawal of the feedback in retention had no detrimental effect on performance.”

• cites C. H. Shea & Wulf, 1999Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

In Riley et al. (1999), touching a curtain significantly reduced postural fluctuation compared with not touching, but only when participants were asked to minimize curtain movements (touch-relevant); when touch was irrelevant, sway was the same as no-touch.

“touching the curtain significantly reduced postural fluctuation,as compared with not touching it, but only when the participants were asked to minimize movements of the curtain resulting from their touch (touchrelevant condition).”

• cites Riley, Stoffregen, Grocki, & Turvey, 1999 sourceNot checked — no full text of the source

May combine two claims.

In C. H. Shea and Wulf (1999), feedback generally enhanced performers' ability to maintain balance on the stabilometer relative to no feedback, even though it could be argued redundant with intrinsic feedback.

“the feedback provided to learners in the C. H. Shea and Wulf (1999) study generally enhanced performers' ability to maintain their balance on the stabilometer, relative to no feedback, even though the feedback could have been argued to be redundant with respect to their intrinsic feedback”

• cites C. H. Shea & Wulf, 1999Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Not yet classified.

In the ski simulator experiment, the pole group produced larger amplitudes than the no-pole group throughout acquisition and demonstrated later relative force onsets, indicating that poles facilitated a more efficient movement pattern.

“As one would expect, the use of poles clearly facilitated performance.That is, the pole group produced larger amplitudes than did the group that practiced without poles throughout the acquisition phase.In addition, the pole group demonstrated later relative force onsets (see Figure 3), indicating that the poles also facilitated the production of a more efficient movement pattern (Wulf, Shea, &”

• cites Wulf, Shea, & Whitacre (1998) sourceNot checked — no full text of the source
• cites Wulf, Shea, & Matschiner, 1998 sourceNot checked — no full text of the source

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

On the stabilometer task, the poles may have prevented the performer from exploring the perceptual-motor workspace; because of the added support, learners kept the platform on target most of the time, did not experience larger deviations from the goal, and consequently did not learn how to reduce deviations without the poles.

“On the stabilometer task, on the other hand, the poles might have prevented the performer from exploring the perceptual-motor workspace.For example, because of the additional support provided by the poles, learners were able to keep the stabilometer platform”

Classified as probably not a substantial claim.

There may be fundamentally more to see and more to be extracted from observation of complex tasks than simple tasks.

“First, there may be fundamentally more to”

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

Prinz's common coding theory argues there is a common representational medium for perception and action.

“Prinz argued that there is a common representational medium for perception and action.”

• cites Prinz, 1990 sourceNot checked — no full text of the source
• cites Prinz, 1997 sourceNot checked — no full text of the source

May combine two claims.

Observational learning is generally considered not as effective as physical practice, but has been demonstrated to be a viable method of practicing complex motor skills.

“For the most part, observational learning, although generally considered not as effective as physical practice, has been demonstrated to be a viable method of practicing complex motor skills”

• cites Bachman, 1961 sourceNot checked — no full text of the source
• cites Landers & Landers, 1973 sourceNot checked — no full text of the source
• cites Martens, Burwitz, & Zuckerman, 1976 sourceNot checked — no full text of the source

Not yet classified.

High-frequency responding is argued to be characteristic of a biological system with more active degrees of freedom, whereas constrained perceptual-motor systems exhibit lower frequency components.

“Highfrequency responding has been argued to be a characteristic of a biologicalsystem with more active degrees of freedom, whereas constrained or compromised perceptualmotor systems exhibit lower frequency components”

• cites Newell & Slifkin, 1996Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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

Prinz and colleagues proposed that actions are planned and controlled by their intended effects (action effect hypothesis).

“Prinz and colleagues (Prinz, 1992(Prinz, , 1997;;Prinz, Aschersleben, Hommel, & Vogt, 1995) and Hommel (1997) have taken up James's and Lotze's ideas that actions are planned and controlled by their intended effects (action effect hypothesis; Prinz, 1997).”

• cites Prinz, 1997 sourceNot checked — no full text of the source

Not yet classified.

In Wulf, McNevin, and Shea (2001), external-focus participants demonstrated lower probe RTs than internal-focus participants, indicating reduced attention demands associated with an external focus.

“External-focus participants demonstrated lower probe RTs than did internal-focus participants, indicating reduced attention demands associated with an external focus.”

• cites Wulf, McNevin, & Shea, 2001 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

Research on focus of attention has been directed only to relatively complex skills.

“In summary, it is important to note that, to date, research on focus of attention has been directed only to relatively complex skills.”

May combine two claims.

Burwitz (1975) found observation beneficial with a Bachman ladder task (complex) and no differences with a pursuit rotor task (simple).

“This issue is illustrated by Burwitz (1975), who found observation beneficial when he used a Bachman ladder task, a relatively complex task, in one experiment and no differences when a pursuit rotor task, a simple task, was used in another experiment.”

• cites Burwitz, 1975Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Probably not a substantial claim: may not pass S1 (asserted), S3 (load-bearing).

Because observers do not execute the movement and do not process direct sensory information, they are not as effective as the model in learning to scale the movement sequence.

“These theorists have argued that because observers do not actually execute the movement and do not process direct sensory information, observers are not as effective as the model, who is physically practicing a skill, in learning to scale the movement sequence.”

• cites Scully & Newell, 1985Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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

Lotze (1852) proposed that movements are represented by codes of their perceived effects, and the desired outcome guides action to achieve it.

“According to Lotze, movements are represented by codes of their perceived effects, and the desired outcome has the power to guide the action so that this outcome is achieved.”

• cites Lotze, 1852Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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

According to the constrained action hypothesis, one advantage of focusing attention on a distant movement effect is that it allows unconscious processes to control movements, resulting in fast adjustments and enhanced performance and learning.

“Thus, one advantage of focusing attention on a (distant) movement effect seems to be that it allows unconscious processes to control the movements required to achieve this effect, resulting in fast movement adjustments and generally enhanced performance and learning.”

• cites McNevin et al., in pressNot matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Not yet classified.

Gould (1980) suggested that observation was more effective when the informational load of the task was high (often complex tasks) than when it was low (typical of simple tasks).

“In a similar vein, Gould (1980) suggested that observation was more effective when the informational load of the task was high, which is often the case for complex tasks, than when it was low, which is more typical of simple tasks.”

• cites Gould, 1980Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

Even though observational practice might not be as effective as physical practice in training specific task characteristics, because some types of important processing are unique to physical practice and cannot be developed effectively during observation, observational practice is viewed as a viable training method for teaching general characteristics of complex tasks.

“Thus, even though observational practice might not be as effective as physical practice in training specific task characteristics, because some types of important processing are unique to physical practice and cannot be developed effectively during observation, observational practice is viewed as a viable training method for teaching general characteristics of complex tasks.”

Classified as probably not a substantial claim.

These results are in line with the view that complex skill learning can be enhanced by reducing attentional and/or motor control demands.

“Thus, these results are in line with the view that complex skill learning can be enhanced by reducing the attentional and/or motor control demands associated with it.”

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

William James (1890) suggested that actions are controlled more effectively if attention is directed to the intended outcome or remote effects rather than close effects such as kinesthetic feedback.

“William James (1890) already had suggested that actions are controlled more effectively if attention is directed to the (intended) outcome of the action, or its”

• cites James, 1890Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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

Todorov et al. showed that learning of table tennis shots was enhanced by concurrent feedback about paddle trajectory relative to expert; participants receiving this feedback were more accurate than those provided verbal feedback on gross errors who hit 50% more balls.

“Todorov et al. showed that the learning of table tennis shots was enhanced by providing performers with concurrent feedback about the trajectory of their paddle (in relation to the paddle trajectory of an expert).Those participants receiving this type of feedback were more accurate in hitting the target than were the participants who were provided verbal feedback (on gross errors) and who hit 50%”

• cites Todorov et al., 1997 sourceNot checked — no full text of the source

Classified as probably not a substantial claim.

According to common coding theory, efferent and afferent codes can be generated and maintained in a commensurate way only at a distal level of representation.

“According to this view, efferent and afferent codes can be generated and maintained in a commensurate way only at a distant level of representation.”

• cites Prinz, 1992 sourceNot checked — no full text of the source

May combine two claims.

When task demands are simple, this memory structuring may not be important, but when demands are high and subcomponents must be integrated, the influence could be much larger.

“When the task demands are relatively simple, this may not be important, but when the demands are high and subcomponents must be properly integrated, the influence could be much larger.”

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

Other experiments have shown little or no benefit of observation.

“However, other experiments have shown little or no benefit of observation (e.g., Brown & Messersmith, 1948;Burwitz, 1975;Wright, Li, & Coady, 1994).”

• cites Brown & Messersmith, 1948 sourceNot checked — no full text of the source
• cites Burwitz, 1975Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Wright, Li, & Coady, 1994 sourceNot checked — no full text of the source

May combine two claims.

Observers appear able to extract information necessary to construct appropriate coordination patterns and determine appropriate implementation strategies.

“However, observers appear to be able to extract information necessary to construct appropriate coordinationpatterns (Schönfelder-Zohdi, 1992;Scully & Newell, 1985;Whiting, 1988) and determine appropriate implementation strategies (Kohl & Shea, 1992).”

• cites Schönfelder-Zohdi, 1992Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Scully & Newell, 1985Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Whiting, 1988 sourceNot checked — no full text of the source

Not yet classified.

McNevin et al. proposed a constrained action hypothesis: performers focusing on body movement or close effect tend to actively intervene in control of movements.

“According to this hypothesis, performers focusing on their body movement, or on an effect that occurs in close proximity to their body, tend to actively intervene in the control of their movements.”

• cites McNevin et al., in pressNot matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Not yet classified.

Burwitz concluded that the benefits of observation were mediated by task difficulty.

“This led Burwitz to conclude that the benefits of observation were mediated by task difficulty.”

• cites Burwitz, 1975Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Not yet classified.

Learning efficiency is especially important for complex skills because they generally take longer to learn, are more physically demanding, carry more risk, and require more specialized equipment or facilities than simple skills.

“The issue of learning efficiency, although relevant to the study of both simple and complex skill learning, is especially important for complex skills, because these skills generally take longer to learn, often are more physically demanding, in many cases introduce the potential for more risk, and generally require more specialized equipment or facilities than do simple skills.”

• AssumptionRests on an assumption: Complex skills generally take longer to learn, are more physically demanding, carry more risk, and require more specialized equipment or facilities than simple skills.

May combine two claims.

Both feedback and an external focus of attention improved learning of the stabilometer task.

“Both feedback and an external focus of attention enhanced learning of the stabilometer task.”

• cites C. H. Shea and Wulf (1999)Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Alternating observational practice with physical practice trials can be quite effective, likely because the observational trials allow information-processing activities that are difficult during a complex, attention-demanding task.

“These findings demonstrate that alternating observational practice with physical practice trials can be quite effective, presumably because the interspersed observational trials give learners the opportunity to perform information-processing activities that they would not be able to do while performing a complex, highly attention-demanding skill.”

May combine two claims.

In the Shebilske et al. (1992) and C. H. Shea et al. (2000) experiments, doubling the number of trained participants without increasing time or resources raised training efficiency by at least 100% while not reducing, and sometimes enhancing, learning effectiveness.

“In the experiments by Shebilske et al. (1992) and C. H. Shea et al. (2000), doubling the number of participants trained without an increase in time and other resources led to increases in training efficiency of at least 100%, while not sacrificing, and even enhancing, learning effectiveness.”

• cites Shebilske et al., 1992 sourceNot checked — no full text of the source
• cites C. H. Shea et al., 2000 sourceNot checked — no full text of the source

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

Giving learners observational practice during rest intervals would improve training efficiency because two or more learners could be trained in the time previously used for one.

“Providing learners with observational practice during rest intervals-for example, by having them watch a partner perform-would enhance training efficiency, since two (or more) learners could be trained in the same amount of time as one.”

May combine two claims.

Random practice does not seem beneficial for learning more complex tasks or for inexperienced learners.

“Furthermore, random practice, which has often been shown to enhance motor learning when simple tasks were used, does not seem to be beneficial for the learning of more complex tasks (or for inexperienced learners); rather, blocked practice can result in more effective learning in these cases (e.g., Albaret & Thon, 1999;Hebert et al., 1996;J. B. Shea & Morgan, 1979).”

• cites Albaret & Thon, 1999 sourceNot checked — no full text of the source
• cites Hebert et al., 1996 sourceNot checked — no full text of the source
• cites J. B. Shea & Morgan, 1979 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S2 (checkable).

Until boundary conditions are determined, valid principles and comprehensive theories cannot be developed.

“Until these boundary conditions are determined, valid principles and, thus, comprehensive theories cannot be developed.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

If physical and observational practice provide distinct processing opportunities that can separately add to learning, then training protocols combining them should be effective.

“If physical and observational practice offer unique opportunities for processing that may independently increment learning, acquisition protocols that combine physical and observational practice should be effective training procedures.”

May combine two claims.

In the Shebilske et al. AIM dyad study, whole-task test games showed no differences between the dyad and individual training groups; both learned the same amount.

“On test games that required control of the whole task, however, there were no differences between groups-that is, both groups showed the same amount of learning (also see Jordan, 1997, for a meta-analysis).”

• cites Jordan, 1997Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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

Simple tasks may benefit less from the reduced processing loads that characterize observational practice.

“Simple tasks, on the other hand, for which cognitive demands tend to be much lower, may not benefit as much from the reduced processing loads characteristic of observational practice.”

• AssumptionRests on an assumption: Simple motor tasks tend to have much lower cognitive demands than complex tasks.

May combine two claims.

Combining observation and physical practice can greatly raise learning efficiency without reducing learning effectiveness.

“It is also important to note that combined observation and physical practice protocols have the potential to greatly increase learning efficiency without sacrificing learning effectiveness (C.H. Shea et al., 2000;C. H. Shea et al., 1999).”

• cites C.H. Shea et al., 2000 sourceNot checked — no full text of the source
• cites C. H. Shea et al., 1999Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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

Observational practice requires less physical energy, lowers injury risk, and does not depend on equipment or specific space as physical practice does.

“Clearly, from a personal standpoint, observational practice requires the expenditure of less physical energy, reduces the risk of injury, and is not dependent on equipment or specific space requirements, as in the case of physical practice.”

• AssumptionRests on an assumption: Observational practice requires less physical energy, reduces injury risk, and is less dependent on equipment or specific space than physical practice.

May combine two claims.

In C. H. Shea et al. (1999), dyad practice caused an initial acquisition decrement relative to individual practice, but dyad participants caught up and tended to be more effective by the end of acquisition.

“Even though there was an initial performance decrement under dyad practice conditions in acquisition, relative to individual practice, the dyad group participants quickly caught up with the individual group participants and even tended to be more effective at the end of the acquisition phase (see Figure 6).”

• cites C. H. Shea et al., 1999Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

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

C. H. Shea et al. (1999) found that practice with a partner was more effective than individual practice.

“The results showed that practice with a partner was more effective than individual practice.”

• cites C. H. Shea et al., 1999Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing), S4 (based).

Including more complex and ecologically valid tasks in research would improve understanding of learning.

“We do believe, however, that the inclusion of more complex and ecologically valid tasks in our research would further enhance our understanding of learning.”

May combine two claims.

Because complex skills are generally more attention demanding, the beneficial effects of observational practice should be clearer for complex tasks.

“Thus, since complex skills are generally more attention demanding, the beneficial effects of observational practice should be seen more clearly for complex tasks.”

• AssumptionRests on an assumption: Complex motor skills generally impose higher attention demands than simple motor skills.