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

In the paper

“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).”

What the sources say

• ?Not matched

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

  cites Vallacher & Wegner, 1985
• Supported

  The “Levels of Identification” section (p. 2) says lower-level identities convey the details of how an action is done, while higher-level identities indicate why it is done or what its effects are. It also describes lower levels as more movement-defined, supporting the citing sentence’s distinction. (LLM, conf=0.94)

  cites Vallacher & Wegner, 1987 source

In the paper

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

What the sources say

• ?Not matched

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

  cites Vallacher & Wegner, 1985
• Supported

  The Levels of Identification section (p. 2) explicitly describes an action’s identity structure as a hierarchical arrangement of identities. The opening summary (p. 1) and Summary and Conclusions (p. 11) connect levels of identification to maintaining and controlling action. (LLM, conf=0.93)

  cites Vallacher & Wegner, 1987 source

In the paper

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

What the sources say

• ?Not matched

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

  cites Vallacher & Wegner, 1985
• Partly 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)

  cites Vallacher & Wegner, 1987 sourceExperimental — accuracy not yet measured

In the paper

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

What the sources say

• ?Not matched

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

  cites Vallacher & Wegner, 1985
• Supported

  The Theoretical Principles section (p. 3) states this as the theory’s second principle: when both lower- and higher-level act identities are available, the higher-level identity tends to become prepotent. The citing sentence accurately paraphrases that principle. (LLM, conf=0.95)

  cites Vallacher & Wegner, 1987 source

In the paper

“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.”

In the paper

“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.”

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites J. B. Shea & Morgan, 1979 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Adams, 1976 source
• ?Not checked — no full text of the sourcecites Schneider & Shiffrin, 1977 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Smith & Davies, 1995 source
• ?Not matched

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

  cites Wrisberg, 1991
• ?Not checked — no full text of the sourcecites Wrisberg & Liu, 1991 source

In the paper

“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”

What the sources say

• ?Not checked — no full text of the sourcecites Magill & Hall, 1990 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites J. B. Shea & Morgan, 1979 source

In the paper

“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.”

In the paper

“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).”

In the paper

“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.”

In the paper

“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.”

In the paper

“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”

What the sources say

• ?Not checked — no full text of the sourcecites Schmidt, 1991a source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Lee, Swinnen, & Serrien, 1994 source
• ?Not checked — no full text of the sourcecites Schmidt & Bjork, 1992 source

In the paper

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

In the paper

“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.”

In the paper

“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”

What the sources say

• ?Not checked — no full text of the sourcecites Schmidt & Wulf, 1997 source
• ?Not checked — no full text of the sourcecites Swinnen, Schmidt, Nicholson, & Shapiro, 1990 source
• ?Not checked — no full text of the sourcecites Vander Linden, Cauraugh, & Greene, 1993 source

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites Lai & Shea, 1998, 1999
• ?Not checked — no full text of the sourcecites Lai, Shea, Wulf, & Wright, 2000 source
• ?Not checked — no full text of the sourcecites C. H. Shea, Lai, Wright, Immink, & Black, 2001 source

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites Tarpy, 1982

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Wright, Li, & Whitacre, 1992 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Winstein & Schmidt, 1990 source
• ?Not checked — no full text of the sourcecites Wulf & Schmidt, 1989 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Schmidt & Wulf, 1997 source
• ?Not checked — no full text of the sourcecites Winstein & Schmidt, 1990 source
• ?Not checked — no full text of the sourcecites Wulf & Schmidt, 1989 source

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Shea, & Matschiner (1998) source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Schmidt, Lange, and Young (1990) source

In the paper

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

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Shea, and Matschiner (1998) source

In the paper

“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”

What the sources say

• ?Not checked — no full text of the sourcecites Povel & Collard, 1982 source

In the paper

“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)”

What the sources say

• ?Not checked — no full text of the sourcecites Lai & Shea, 1998 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Shea, & Matschiner (1998) source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Guadagnoli et al. (1996) source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Salmoni et al., 1984 source
• ?Not checked — no full text of the sourcecites Schmidt, 1991a source

In the paper

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

In the paper

“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)”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Hörger, and Shea (1999) source

In the paper

“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”

What the sources say

• ?Not checked — no full text of the sourcecites Schmidt & Wulf, 1997 source
• ?Not checked — no full text of the sourcecites Vander Linden et al., 1993 source
• ?Not checked — no full text of the sourcecites Winstein et al., 1996 source

In the paper

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

In the paper

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

In the paper

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

In the paper

“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.”

In the paper

“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.”

In the paper

“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.”

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites Newell, 1991 source

In the paper

“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”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf & Weigelt, 1997 source

In the paper

“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.”

In the paper

“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”

In the paper

“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”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Höß, & Prinz, 1998 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Todorov, Shadmehr, & Bizzi, 1997 source

In the paper

“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).”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Shea, & Park, 2001 source

In the paper

“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.”

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites Wulf et al., in press

In the paper

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

In the paper

“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”

What the sources say

• ?Not matched

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

  cites Schmidt, 1988
• ?Not matched

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

  cites Schmidt, 1991b
• ?Not matched

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

  cites Schmidt & Wrisberg, 2000

In the paper

“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).”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Höß, & Prinz, 1998 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Shea, & Whitacre (1998) source

In the paper

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

In the paper

“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”

What the sources say

• ?Not matched

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

  cites C. H. Shea & Wulf, 1999

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Lauterbach, & Toole, 1999 source

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Singer, Lidor, & Cauraugh, 1993 source

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites Wulf et al., in press

In the paper

“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.”

In the paper

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

What the sources say

• ?Not matched

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

  cites C. H. Shea & Wulf, 1999

In the paper

“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).”

What the sources say

• ?Not checked — no full text of the sourcecites Riley, Stoffregen, Grocki, & Turvey, 1999 source

In the paper

“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”

What the sources say

• ?Not matched

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

  cites C. H. Shea & Wulf, 1999

In the paper

“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, &”

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, Shea, & Whitacre (1998) source
• ?Not checked — no full text of the sourcecites Wulf, Shea, & Matschiner, 1998 source

In the paper

“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”

In the paper

“First, there may be fundamentally more to”

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites Prinz, 1990 source
• ?Not checked — no full text of the sourcecites Prinz, 1997 source

In the paper

“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”

What the sources say

• ?Not checked — no full text of the sourcecites Bachman, 1961 source
• ?Not checked — no full text of the sourcecites Landers & Landers, 1973 source
• ?Not checked — no full text of the sourcecites Martens, Burwitz, & Zuckerman, 1976 source

In the paper

“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”

What the sources say

• ?Not matched

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

  cites Newell & Slifkin, 1996

In the paper

“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).”

What the sources say

• ?Not checked — no full text of the sourcecites Prinz, 1997 source

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites Wulf, McNevin, & Shea, 2001 source

In the paper

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

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites Burwitz, 1975

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites Scully & Newell, 1985

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites Lotze, 1852

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites McNevin et al., in press

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites Gould, 1980

In the paper

“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.”

In the paper

“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.”

In the paper

“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”

What the sources say

• ?Not matched

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

  cites James, 1890

In the paper

“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%”

What the sources say

• ?Not checked — no full text of the sourcecites Todorov et al., 1997 source

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites Prinz, 1992 source

In the paper

“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.”

In the paper

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

What the sources say

• ?Not checked — no full text of the sourcecites Brown & Messersmith, 1948 source
• ?Not matched

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

  cites Burwitz, 1975
• ?Not checked — no full text of the sourcecites Wright, Li, & Coady, 1994 source

In the paper

“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).”

What the sources say

• ?Not matched

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

  cites Schönfelder-Zohdi, 1992
• ?Not matched

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

  cites Scully & Newell, 1985
• ?Not checked — no full text of the sourcecites Whiting, 1988 source

In the paper

“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.”

What the sources say

• ?Not matched

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

  cites McNevin et al., in press

In the paper

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

What the sources say

• ?Not matched

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

  cites Burwitz, 1975

In the paper

“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.”

In the paper

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

What the sources say

• ?Not matched

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

  cites C. H. Shea and Wulf (1999)

In the paper

“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.”

In the paper

“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.”

What the sources say

• ?Not checked — no full text of the sourcecites Shebilske et al., 1992 source
• ?Not checked — no full text of the sourcecites C. H. Shea et al., 2000 source

In the paper

“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.”

In the paper

“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).”

What the sources say

• ?Not checked — no full text of the sourcecites Albaret & Thon, 1999 source
• ?Not checked — no full text of the sourcecites Hebert et al., 1996 source
• ?Not checked — no full text of the sourcecites J. B. Shea & Morgan, 1979 source

In the paper

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

In the paper

“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.”

In the paper

“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).”

What the sources say

• ?Not matched

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

  cites Jordan, 1997

In the paper

“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.”

In the paper

“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).”

What the sources say

• ?Not checked — no full text of the sourcecites C.H. Shea et al., 2000 source
• ?Not matched

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

  cites C. H. Shea et al., 1999

In the paper

“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.”

In the paper

“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).”

What the sources say

• ?Not matched

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

  cites C. H. Shea et al., 1999

In the paper

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

What the sources say

• ?Not matched

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

  cites C. H. Shea et al., 1999

In the paper

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

In the paper

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