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Augmented feedback is information provided to the learner from an external source. It is the general term used to describe information given about the performance of a skill that enhances the intrinsic feedback that is naturally available from performers’ senses (i.e.

their auditory, proprioceptive and visual systems). Augmented feedback can be provided verbally or non-verbally, during (concurrent feedback), immediately following (terminal feedback), or some period after the completed skill (delayed feedback), and can include information about the movement outcome (knowledge of results [KR]) and/or the movement pattern (knowledge of performance [KP]).

From the coach’s perspective, the most important question when considering whether to use augmented feedback is: can it help in the acquisition of the to-be-learned skill?

Unfortunately, the answer to this question is not simple as (similar to the earlier discussion on how to best structure the practice environment) it is dependent on both individual and task factors. Firstly, there may be situations where augmented feedback is not required, as the task-intrinsic feedback alone provides sufficient information for skill learning to occur.

In these situations, athletes can make appropriate future adjustments to their movements based on their own sensory feedback from either their individual performances or by observing others of the same (Herbert and Landin 1994), or higher, skill level (Magill and Schoenfelder-Zohdi 1996). However, if athletes cannot utilise intrinsic feedback to enhance their performance, then augmented feedback is essential for skill acquisition. This situation can occur due to a number of reasons, such as injury, task constraints and skill level. For example, when an individual who, through injury, has damaged essential mechanisms for

the detection and/or utilisation of task-intrinsic feedback, or where the constraints of the task mean that critical intrinsic feedback is not readily available, augmented feedback must be presented if learning is to occur. In addition, there may be situations where task-intrinsic feedback is readily available, yet it is not immediately useful to the learner due to his or her limited experience in perceiving its meaning. These situations often occur during the early stages of learning. Here, then, augmented feedback can help the novice learner better understand the meaning of the task-intrinsic feedback. However, this process can sometimes be problematic as, if the task-intrinsic feedback is minimal or perceived as overly difficult to understand, augmented feedback may actually reduce learning. This occurs if the learner substitutes the intrinsic feedback with the offered augmented feedback, subsequently becoming reliant on the latter for accurate performance. Consequently, when augmented feedback is not available, such as in a game situation, a decrease in performance is likely to occur. This is referred to in the motor learning literature as the guidance hypothesis (Salmoni et al. 1984) and will be further discussed later in this chapter.

Types of augmented feedback

Verbal feedback provided by coaches is perhaps the most commonly used form of augmented feedback in the practice environment. However, there are a number of other ways of providing augmented feedback. An increasingly utilised form is through video.

However, for videotape feedback to be effective at least two important factors need to be considered: the learner’s skill level and the period of time for which this type of feedback is utilised (Rothstein and Arnold 1976). Here, research suggests that skilled performers benefit from unaided video replays of their performance, whereas novices tend to be overwhelmed by the information available in the video and require the addition of specific verbal cues to point out critical information (Newell and Walter 1981; Rothstein and Arnold 1976).

Research has also suggested that learners need sufficient time to familiarise themselves with video replays as a form of augmented feedback so they can understand what information is important to extract and act upon. Whilst it may be possible to reduce this time period by providing attention-focusing cues as described above, it has been recommended that video replays should be utilised for at least five weeks in order to become an effective teaching/learning tool (Rothstein and Arnold 1976).

Another useful form of augmented feedback is biofeedback. Here information is presented to the athlete about internal physiological actions such as heart rate, muscle activity and/

or joint movement. This form of augmented feedback is generally used in the clinical setting for the purpose of rehabilitation (Brucker and Bulaeva 1996; Intiso et al. 1994;

Shumway-Cook et al. 1988). However, it has also been used in the sporting environment to enhance the learning and performance of both skilled swimmers, by providing audible signals about their stroke rate (Chollet et al. 1988), and elite rifle shooters, by providing audio signals enabling them to shoot between potentially disruptive heartbeats (Daniels and Landers 1981).

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The frequency and timing of augmented feedback

While the skill level of the performer and the characteristics of the task need to be taken into account when deciding if and what type of augmented feedback is required for skill learning, it is also important to consider the amount and frequency of such feedback as well as its timing (i.e. when it should be given). Early views regarding the presentation of augmented feedback suggested that ‘the greater the amount the better the learning’, and that it should, therefore, be presented after every practice. However, this view is no longer tenable following the emergence of the guidance hypothesis (Salmoni et al. 1984).

According to the guidance hypothesis, if the learner receives augmented feedback after every trial they may develop a dependency on it, thus undermining the benefits of important intrinsic sensory feedback required for error detection and correction (Bjork 1988; Schmidt 1991). Consequently, when augmented feedback is not available, performance suffers, as the learner has come to rely upon it to produce the required skill effectively. A number of studies have been carried out examining augmented feedback using a variety of techniques (e.g. Winstein and Schmidt 1990, Janelle et al. 1995), the results of which appear to support the guidance hypothesis. Specifically, the research indicates that low-frequency feedback schedules are advantageous to skill learning because they promote problem-solving and encourage learners to explore the dynamics of a skill while utilising task-intrinsic feedback.

A common misconception with regard to the timing of augmented feedback is that it should be provided as soon as possible after completion of the practice trial, because any delay results in the learner forgetting the skill. Research, however, does not support this.

Rather, it has demonstrated that there must be a minimum time period given to the learner before augmented feedback is presented (Swinnen et al. 1990). This is in accordance with the principles of the guidance hypothesis, which suggests that if the KR delay is too short the learner is unable to fully engage in important intrinsic error detection and correction mechanisms, thus compromising the learning.

A second important timing issue relates to the interval between the presentation of augmented feedback and the beginning of the next practice trial (the post-KR delay).

Whilst there is no evidence indicating an optimal period for this interval or an upper limit, the general conclusion is that it can be too short (Gallagher and Thomas 1980; Rogers 1974). This is because the learner requires sufficient time to process both the augmented feedback and the task-intrinsic feedback from the previous trial to produce an action plan for the subsequent response. Thus, for optimal learning, the post-KR delay should be long enough to permit these important learning processes to occur.

To conclude, primary considerations when using augmented feedback are to assess both the characteristics of the learner (e.g. the skill level) and the nature of the to-be-learned skill (i.e. the amount of available task-intrinsic feedback during execution of the skill). These will determine what role additional feedback could play in learning (e.g. is it necessary for learning to occur?). If augmented feedback is deemed necessary for skill learning, a number of different types of presentation techniques are available to the coach. These include verbal, video replays and biofeedback, the merits of which again depend on individual and

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task factors. For example, video replays are particularly useful to skilled performers (Rothstein and Arnold 1976), although in order to be effective for beginners, videos should be supplemented with cues designed to focus the learners’ attention on critical aspects of the skill (Kernodle and Carlton 1992; Newell and Walter 1981). Finally, in line with the guidance hypothesis (Salmoni et al. 1984), the frequency and timing of presenting augmented feedback should be considered in order to facilitate optimal learning.