Attention and motor performance: preferences for and advantages of an external focus.

This study examined individuad differences in the preference for and effectiveness of the type of attentional focus for motor learning. In two experiments, participants practicing a balance task (stabilometer) were asked to find out whether focusing on their feet (internal focus) or on two markets in front of their feet (external focus) was more effective. In Experiment 1, participants switched their attentional focus from trial to trial on Day 1 and used their preferred attentional focus on Day 2. In Experiment 2, participants were free to switch their attentional focus any time during 2 days of practice. Retention tests were performed on Day 3. Most participants chose an external focus. Also, they were more effective in retention than participants who preferred an internal focus.     

Spatial assimilation effects and error detection in rapid overlapping and sequential bimanual movements.

This study verified earlier anecdotal evidence indicating that spatial assimilations could be reduced by offsetting movements in time. In Experiment 1, 40 right-handed participants (ages 18-23 years) made single and dual quick lever reversals of 20 degrees and 60 degrees with the left and right limbs, respectively. Participants were assigned to either the Overlapping (O) group, in which one limb began when the other limb reached the reversal point, or to the Sequential (S) group in which one limb followed the other with a delay of 114 ms, on average. The shorter-distance limb of the O group overshot relative to the S group. Short-distance spatial assimilations were also shown in the S group in Experiment 2, when the delay was increased to 250, 500, or 1,500 ms (N = 30), suggesting that assimilation effects can be caused by command interactions at both the planning and the execution levels.     

Benefits of an external focus of attention: common coding or conscious processing?

We conducted two experiments to assess the effect attentional focus has on learning a complex motor skill and subsequent performance under secondary task loading. Participants in Experiment 1 learnt a golf putting task (300 practice trials) with a single instruction to either focus on their hands (internal focus) or the movement of the putter (external focus). No group differences were evident during learning or retention. Differences between the groups were only apparent under secondary task load; the external group's performance remained robust, while the internal group suffered a drop in performance. Verbal protocols demonstrated that the internal group accumulated significantly more internal knowledge and more task-relevant knowledge in general than the external group. Experiment 2 was designed to establish whether greater internal focus knowledge or greater explicit rule build up in general was responsible for performance breakdown. Two groups were presented with a set of six internal or external rules. Again, no performance differences were found during learning or retention. During the secondary task, both groups experienced performance deterioration. It was concluded that accumulation of explicit rules to guide performance was responsible for the internal group's breakdown in performance under secondary task loading and may be responsible for some of the performance differences reported previously.     

Forthcoming events

Abstract

We conducted two experiments to assess the effect attentional focus has on learning a complex motor skill and subsequent performance under secondary task loading. Participants in Experiment 1 learnt a golf putting task (300 practice trials) with a single instruction to either focus on their hands (internal focus) or the movement of the putter (external focus). No group differences were evident during learning or retention. Differences between the groups were only apparent under secondary task load; the external group's performance remained robust, while the internal group suffered a drop in performance. Verbal protocols demonstrated that the internal group accumulated significantly more internal knowledge and more task-relevant knowledge in general than the external group. Experiment 2 was designed to establish whether greater internal focus knowledge or greater explicit rule build up in general was responsible for performance breakdown. Two groups were presented with a set of six internal or external rules. Again, no performance differences were found during learning or retention. During the secondary task, both groups experienced performance deterioration. It was concluded that accumulation of explicit rules to guide performance was responsible for the internal group's breakdown in performance under secondary task loading and may be responsible for some of the performance differences reported previously.     

Distance and location assimilation effects in rapid bimanual movement

When subjects make simultaneous aiming movements of the upper limbs over different distances, assimilation effects are shown; the shorter distance limb overshoots when paired with a longer distance limb. However, it is not known whether assimilation effects are due to variations in distance per se or to variations in target location. To separate the possible influences of distance and location, 60 subjects made rapid bimanual aiming movements in one of four conditions. The two different-distance groups made a 20 degrees movement in the left hand and a 60 degrees movement in the right hand to either the same or different target locations. The comparison groups moved 20 degrees in each limb. Somewhat surprisingly, spatial assimilations were greater when moving different distances to the same, rather than different, target locations, which suggests interlimb differences in distance mediate assimilation effects rather than target location. Temporal assimilations were greater when distance and location were varied, but the assimilations were not related to interlimb differences in velocity, as predicted by Marteniuk and MacKenzie (1980).     

The locus of focus: the effect of switching from a preferred to a non-preferred focus of attention

Focusing strategies are known to play a significant role in motor performance, with individuals who use an internal focus on body movement typically showing poorer outcomes than those who focus on features of the external environment. Focus of attention and switching of one's focus are examined in the context of two different complex motor skills along with a factor not previously examined systematically, individual preference. In both experiments, participants were introduced to focusing strategies that might be employed when attempting a sensorimotor task. Explanations of both strategies were given to participants. Specifically, for an internal focus, participants were instructed to concentrate on their body movements, while for an external focus, they were instructed to focus on aspects in the environment. They were then asked which strategy they preferred. Participants then continued either with their preferred focus or were instructed to switch to their non-preferred focus. The advantage that the external focus typically enjoys turns out not to be a simple one and interacts with individual preference and with the "forced-opposite" manipulation. Our results support the growing consensus that encouraging individuals to adopt an internal focusing strategy is counterproductive in complex sensorimotor tasks. They also suggest that individual preferences play a role.     

Learning a coordination skill: interactive effects of instruction and feedback

Information prior to and during the acquisition of a continuous bimanual task was manipulated. Participants practiced a difficult coordination pattern, which produced circular shapes on the computer, when they moved their arms correctly. Four groups were examined, which differed in the type and amount of information provided. Either limb or circle feedback was provided in the presence or absence of instructions detailing how to move the limbs. Circle feedback facilitated learning relative to the limb feedback in which the explicit displacements of the limbs was displayed. Under circle feedback conditions, instructions hindered acquisition. Little instructional effects were observed under limb feedback conditions, despite the prediction that instructions would benefit learning when the feedback was more compatible. Findings are discussed in relation to the complexity of the feedback and processing demands.     

Internal and external focus of attention in a novice form sport

In the current experiment, we examined optimal focus for novices during a movement sequence in which performance was measured on accurate movement form/technique. A novel gymnastics routine was practiced under either an internal skill-relevant, internal skill-irrelevant, external, or no attention focus. Retention and transfer tests were then completed. During acquisition, adopting an internal irrelevant focus significantly improved performance, whereas an external focus degraded performance. There were no significant group differences in the retention and transfer tests. This suggests that learning of movement form/technique did not benefit from a specific focus of attention. The results are interpreted via an attentional capacity viewpoint and the notion that form tasks do not always contain obvious movement effects central to common coding and the constrained action hypothesis.     

The locus of focus: The effect of switching from a preferred to a non-preferred focus of attention

Abstract

Focusing strategies are known to play a significant role in motor performance, with individuals who use an internal focus on body movement typically showing poorer outcomes than those who focus on features of the external environment. Focus of attention and switching of one's focus are examined in the context of two different complex motor skills along with a factor not previously examined systematically, individual preference. In both experiments, participants were introduced to focusing strategies that might be employed when attempting a sensorimotor task. Explanations of both strategies were given to participants. Specifically, for an internal focus, participants were instructed to concentrate on their body movements, while for an external focus, they were instructed to focus on aspects in the environment. They were then asked which strategy they preferred. Participants then continued either with their preferred focus or were instructed to switch to their non-preferred focus. The advantage that the external focus typically enjoys turns out not to be a simple one and interacts with individual preference and with the “forced-opposite” manipulation. Our results support the growing consensus that encouraging individuals to adopt an internal focusing strategy is counterproductive in complex sensorimotor tasks. They also suggest that individual preferences play a role.     

A Method for Rapid Collection and Processing of Isokinetic Data

Abstract

This study verified earlier anecdotal evidence indicating that spatial assimilations could be reduced by offsetting movements in time. In Experiment 1, 40 right-handed participants (ages 18–23 years) made single and dual quick lever reversals of 20° and 60° with the left and right limbs, respectively. Participants were assigned to either the Overlapping (O) group, in which one limb began when the other limb reached the reversal point, or to the Sequential (S) group in which one limb followed the other with a delay of 114 ms, on average. The shorter-distance limb of the O group overshot relative to the S group. Short-distance spatial assimilations were also shown in the S group in Experiment 2, when the delay was increased to 250, 500, or 1,500 ms (N = 30), suggesting that assimilation effects can be caused by command interactions at both the planning and the execution levels.     

The influence of audience and monetary reward on the putting kinematics of expert and novice golfers

We investigated changes in movement kinematics and attentional focus when expert and novice golfers performed a golf-putting task under pressure. Six male professional golfers and five male novice golfers performed 100 acquisition trials, followed by 10 trials in the pressure condition with a performance-contingent cash reward and small audience. After the 10 trials in the pressure condition, participants answered a questionnaire concerning attentional focus during both types of trial, including such aspects as conscious control of movements and the effects of distraction. A pressure manipulation check revealed a modest increase in physiological arousal, in that heart rate increased by about 10 bpm although state anxiety did not increase. A two-dimensional analysis of movement kinematics revealed that the amplitudes of arm and club movements decreased on the backswing in the pressure condition. Arm and club movement speed decreased on the foreswing in both experts and novices. Furthermore, neither experts nor novices changed their attentional focus in the pressure condition. Whereas previous studies of "choking under pressure" focused on attentional changes, the kinematic changes found in the present study were possibly caused by the influences of strategy modification and/or emotional response. Choking phenomena can be explained by attentional changes, along with the influences of strategy modification and/or emotional response under pressure.     

Internal and External Focus of Attention in a Novice Form Sport

Abstract

In the current experiment, we examined optimal focus for novices during a movement sequence in which performance was measured on accurate movement form/technique. A novel gymnastics routine was practiced under either an internal skill-relevant, internal skill-irrelevant, external, or no attention focus. Retention and transfer tests were then completed. During acquisition, adopting an internal irrelevant focus significantly improved performance, whereas an external focus degraded performance. There were no significant group differences in the retention and transfer tests. This suggests that learning of movement form/technique did not benefit from a specific focus of attention. The results are interpreted via an attentional capacity viewpoint and the notion that form tasks do not always contain obvious movement effects central to common coding and the constrained action hypothesis.     

External-Focus Feedback Benefits Free-Throw Learning in Children

Purpose: Considerable research supports the motor-learning advantage associated with an external focus of attention; however, very few studies have attempted to generalize these findings to children especially with attentional focus feedback. Therefore, the purpose of this study was to determine the effect of attentional focus feedback on motor learning in children. Method: Boys (n = 14) and girls (n = 14) aged 9 to 11 years old were randomly assigned to 1 of 2 gender-stratified groups: (a) internal-focus feedback or (b) external-focus feedback. Following initial instructions and task demonstration, participants performed 100 modified free throws over 2 days while receiving feedback statements respective to their attentional focus condition. Approximately 24 hr later, participants performed a retention test consisting of 20 additional free throws. Participants were also asked to respond to a retrospective verbal report at the end of each day to serve as a manipulation check. Results: Results of the analysis revealed a statistically significant learning advantage for participants receiving external-focus feedback, and retrospective verbal reports provide support for the self-invoking trigger and constrained action hypotheses. Conclusions: Future research should continue to incorporate retrospective verbal reports and explore potential causal links between internal attentional focus and self-evaluation.     

What determines limb selection for reaching?

While motor dominance appears to drive limb selection for reaching movements at the midline and ipsilateral (dominant) side, this study examined the possible determinants associated with what drives the programming of movements in response to stimuli presented in contralateral space. Experiment 1 distinguished between object proximity and a hemispheric bias for using the hand on the same side as the stimulus by comparing imagined and actual reaching with arms uncrossed and crossed. Experiment 2 examined the role of comfort in limb selection via participants reaching for a cube under two conditions: 1- and multiple-df movements. The first experiment demonstrated a proximity effect; participants preferred to keep their arms crossed to reach with the hand closest to the stimulus rather than uncrossing their arms to support a bias. Comfort was eliminated when participants continued to prefer the nondominant hand, even though they were able to reach with the dominant hand at all positions using only a 1-df movement. In summary, we offer evidence suggesting that limb selection in response to stimuli presented in contralateral hemispace is determined primarily by information related to the proximity between the stimulus and the hand.     

The Reliability of the [Vdot]O2-HR Relation during Graded Treadmill Exercise in Prepubertal Boys and Adult Men

Abstract

When subjects make simultaneous aiming movements of the upper limbs over different distances, assimilation effects are shown; the shorter distance limb overshoots when paired with a longer distance limb. However, it is not known whether assimilation effects are due to variations in distance per se or to variations in target location. To separate the possible influences of distance and location, 60 subjects made rapid bimanual aiming movements in one of four conditions. The two different-distance groups made a 20° movement in the left hand and a 60° movement in the right hand to either the same or different target locations. The comparison groups moved 20° in each limb. Somewhat surprisingly, spatial assimilations were greater when moving different distances to the same, rather than different, target locations, which suggests interlimb differences in distance mediate assimilation effects rather than target location. Temporal assimilations were greater when distance and location were varied, but the assimilations were not related to interlimb differences in velocity, as predicted by Marteniuk and MacKenzie (1980).     

Attentional focus effects in balance acrobats

Performing and learning motor skills has been shown to be enhanced if the performer adopts an external relative to internal focus (or no focus) of attention (Wulf 2007). The present study examined the generalizability of this effect to top-level performers (balance acrobats). Participants performed a balance task (standing on an inflated rubber dish) under each of three attentional focus conditions: (a) external focus (i.e., minimize movements of the disk), (b) internal focus (i.e., minimize movements of the feet), and (c) control conditions (no focus instructions). While there were no differences between conditions in the amount of postural sway, the frequency of movement adjustments was higher in the control condition, relative to both external and internal focus conditions. This suggests that movement automaticity and postural stability were greatest when the balance experts were free to adopt their "normal" focus of attention. The finding implies that there may be a limit to the performance-enhancing effects of external focus instructions for top-level performers. The findings are discussed in terms of action control levels and possible changes in the optimal attentional focus with the performer's level of expertise.     

The end-state comfort effect in bimanual grip selection

During a unimanual grip selection task in which people pick up a lightweight dowel and place one end against targets at variable heights, the choice of hand grip (overhand vs. underhand) typically depends on the perception of how comfortable the arm will be at the end of the movement: an end-state comfort effect. The two experiments reported here extend this work to bimanual tasks. In each experiment, 26 right-handed participants used their left and right hands to simultaneously pick up two wooden dowels and place either the right or left end against a series of 14 targets ranging from 14 to 210 cm above the floor. These tasks were performed in systematic ascending and descending orders in Experiment 1 and in random order in Expiment 2. Results were generally consistent with predictions of end-state comfort in that, for the extreme highest and lowest targets, participants tended to select opposite grips with each hand. Taken together, our findings are consistent with the concept of constraint hierarchies within a posture-based motion-planning model.     

Differences in 3D kinematics between volleyball and beach volleyball spike movements

The purpose of this study was to identify differences between volleyball and beach volleyball spike jump movements performed on an indoor surface and sand surface respectively. Eight elite male volleyball players performed spike jump movements on both surfaces. An eight-camera motion capturing system (250Hz) was used to generate 3D kinematic data. Seven groups of variables representing the kinematics of the centre of mass, the countermovement, the approach phase, and the angular amplitudes and maximal velocities of the lower and upper limbs were examined using Hotelling's T2(2). Significant differences were observed in the movement of the centre of mass (P < 0.05), the countermovement, the kinematics of the approach phase, and the angular amplitudes of the lower limbs. However, no significant differences were observed either in the maximal angular velocities of the lower and upper limbs, or in the amplitudes of the upper limb motion. In conclusion, the participants showed significant adaptation to changed movement conditions. As a result of the compliance of the sand surface, the participants slowed down their movements, especially during the phase of transition from knee flexion to extension and during the extension phase. Furthermore, the participants demonstrated changes in foot position to reach the greatest height possible.     

Retroactive interference effects of mentally imagined movement speed

In two retroactive interference experiments, we assessed the effect of mentally imagined movement speed on subsequent motor performance. All participants performed a sequential motor action at three speeds during a baseline test and a retention test. During the retention interval of Experiment 1, the participants (n = 50) physically performed the action at a slow speed, physically performed it at a fast speed, imagined it at a slow speed, imagined it at a fast speed, or performed a no-practice control task. In Experiment 2, the participants (n = 24) imagined the movement, overtly vocalized words, or both, all at a slow speed. The results revealed that the speed of the imagined motor action affected the speed of subsequent performance in the retention test and that imagery and physical practice were functionally equivalent. The results are consistent with Lang's bio-informational theory.     

Attentional focus effects on sprint start performance as a function of skill level

Abstract

Several researchers have demonstrated that an external focus of attention (about movement’s effects) during movement execution allowed better performances and learning of various motor tasks than an internal focus of attention (about movement itself). However, attentional focus effects have not been studied in tasks requiring explosive actions preceded by fast reaction time to a signal, such as a sprint start. We hypothesised that the beneficial effect of external focus of attention would be observed in the different stages of the sprint start (i.e. reaction time, block clearance and running) for both expert and novice sprinters. Novice and expert sprinters performed sprint starts followed by a 10 m sprint under three conditions: external focus instructions; internal focus instructions; and neutral instructions. The reaction time and the running time were significantly shorter in the external focus condition than in the internal focus condition, for both expert and novice participants. These results confirm the beneficial effect of an external focus of attention on the speed of movement execution. Moreover, they revealed that attentional focus influences movement preparation. Several hypotheses are proposed to account for these results, with reference to the processes that could be responsible for the observed effects.