Relationships between the magnitude of representational momentum and the spatial and temporal anticipatory judgments of opponent’s kicks in taekwondo

For successful actions in a fast, dynamic environment such as sports, a quick successful anticipation of a forthcoming environmental state is essential. However, the perceptual mechanisms involved in successful anticipation are not fully understood. This study examined the relationships between the magnitude of representational momentum (RM) as a forward displacement of the memory representation of the final position of a moving object (which implies that observers perceptually “see” a near future forthcoming dynamic environmental state) and the temporal and spatial anticipatory judgments of the opponent’s high or middle kicks in taekwondo. Twenty-seven participants (university taekwondo club members and non-members) observed video clips of taekwondo kicks that vanished at one of 10 frame positions prior to the kick impact and performed three tasks consecutively: anticipatory coincidence timing (CT) with the arrival of kick impact, judgment of the kick type (high and middle kicks) by forced choice, and judgment of the vanishing frame position (measuring RM). Our results showed significant group effects for the number of correct kick-type judgments and the judgment threshold for kick-type choice (kick-typeJT), which was estimated in terms of individual psychometric function curves. A significant correlation was found between the magnitude of RM (estimated at kick-typeJT) and kick-typeJT, but not between the CT errors (estimated at kick-typeJT) and kick-typeJT. This indicates that the magnitude of RM may play an influential role in quick kick-type judgments, but not in coincidence timing while observing an opponent’s kick motion. These findings suggest that subjective anticipatory perception or judgment of the future spatial state is vital to anticipatory actions under severe time constraints

Behavioural Models of Motor Control and Short-Term Memory

We examined in this review article the behavioural and conceptual models of motor control and short-term memory which have intensively been investigated since the 1970s. First, we reviewed both the dual-storage model of short-term memory in which movement information is stored and a typical model of motor control which emphasizes the importance of efferent factors. We then examined two models of preselection effects: a cognitive model and a cognitive/ efferent model. Following this we reviewed specific models of the control of movement endlocation (the mass-spring model) and of movement distance (the coding strategy explanations). Finally, we discussed the contribution of both kinesthetic signals and abstract code to the storage of location and distance information for controlling limb movements

Behavioral and Methodological Issues in Motor Short-Term Memory and its Basic Experimental Paradigm

We examined in this study the basic behavioral correlates of motor short-term memory and several methodological issues with respect to the investigative paradigm. We first reviewed pioneering studies on motor short-term memory and then addressed methodological issues including dependent measures, directional biasing effects, and separation of movement cues. Finally, we examined the methodological aspects of the typical investigative paradigm used in motor short-term memory research

The mediating effect of learning on the interference between location and distance recall from motor short-term memory

Two experiments were conducted within a motor short-term memory paradigm to examine the influence of shifts in starting position upon the reproduction of movement location (experiment 1) and distance (experiment 2). We assessed whether the systematic pattern of undershooting and overshooting which occurs as a function of starting position changes is a consequence of learning which proceeds throughout the course of an experiment or is rather a more fundamental property of the encoding and retrieval processing occurring within motor short-term memory. Five groups of 10 subjects were each given 20 trials within a typical motor short-term memory paradigm. Each trial involved a criterion and reproduction linear-positioning movement separated by a 10-sec retention interval. The starting position for the reproduction movement was shifted by 0, 2 or 4 cm in either direction from the starting position of the criterion movement. The presentation order of the five shifts in starting position was counterbalanced among the five groups, and each group consecutively performed 4 trials per shift. Analysis of data obtained from only the starting position condition performed first by each of the subjects showed the same systematic pattern of undershooting and overshooting in movement reproduction as observed from the typical analysis based on the data obtained from all the starting position conditions. These results suggest that the systematic undershooting-overshooting pattern typically observed in motor short-term memory experiments is not a consequence of any learning which takes place during the course of the experiment and is hence not an artifact of any central tendency effects arising from exposure to a range of different movement distances and locations. Rather location-distance interference appears to result from more fundamental aspects of the encoding and retrieval of information from motor short-term memory

Interference between location and distance information in motor short-term memory: The respective roles of direct kinesthetic signals and abstract codes

Interference between location and distance information in motor short-term memory has been hypothesized on the basis of the systematic pattern of undershooting and overshooting in movement reproduction that occurs when the starting position for reproduction movements is shifted. To determine the possible contribution of limb-specific kinesthetic information to this systematic undershooting–overshooting pattern, we compared the reproduction of linear arm positioning movements performed under either same-limb or switched-limb conditions. Ten subjects were assigned to either a location or distance cue condition, and each subject completed a total of 40 trials, 20 under same-limb and 20 under switched-limb conditions. Each trial consisted of criterion and reproduction movements, separated by a 10-s retention interval. The starting position for the reproduction movement was shifted by 0, 2, or 4 cm in either direction from that of the criterion movement. The systematic undershooting–overshooting pattern, which occurs when either the movement location or distance is reproduced, arose under both the same-limb and switched-limb conditions, suggesting that the primary cause of the location-distance interference is not limb-specific kinesthetic information. Rather, more abstract information in the form of a conceptual memory code appears to be the probable cause of the locationdistance interference phenomenon

Motor preparation of manual aiming at a visual target manipulated in size, luminance contrast, and location

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Rule for scaling shoulder rotation angles while walking through apertures.

BACKGROUND: When an individual is trying to fit into a narrow aperture, the amplitude of shoulder rotations in the yaw dimension is well proportioned to the relative aperture width to body width (referred to as the critical ratio value). Based on this fact, it is generally considered that the central nervous system (CNS) determines the amplitudes of shoulder rotations in response to the ratio value. The present study was designed to determine whether the CNS follows another rule in which a minimal spatial margin is created at the aperture passage; this rule is beneficial particularly when spatial requirements for passage (i.e., the minimum passable width) become wider than the body with an external object. METHODOLOGY/PRINCIPAL FINDINGS: Eight young participants walked through narrow apertures of three widths (ratio value = 0.9, 1.0, and 1.1) while holding one of three horizontal bars (short, 1.5 and 2.5 times the body width). The results showed that the amplitude of rotation angles became smaller for the respective ratio value as the bar increased in length. This was clearly inconsistent with the general hypothesis that predicted the same rotation angles for the same ratio value. Instead, the results were better explained with a new hypothesis which predicted that a smaller rotation angle was sufficient to produce a constant spatial margin as the bar-length increased in length. CONCLUSION: The results show that, at least under safe circumstances, the CNS is likely to determine the amplitudes of shoulder rotations to ensure the minimal spatial margin being created at one side of the body at the time of crossing. This was new in that the aperture width subtracted from the width of the body (plus object) was taken into account for the visuomotor control of locomotion through apertures

The essential role of optical flow in the peripheral visual field for stable quiet standing: Evidence from the use of a head-mounted display.

It has long been thought that vision is the most essential factor in maintaining stable quiet standing compared to other sources (i.e., vestibular and somatosensory inputs) of information. Specifically, several vision studies on postural control have shown evidence for the importance of the visual system, particularly peripheral vision rather than central vision, and optical flow. Nevertheless, to date, no study has manipulated both visual field and optical flow concurrently. In the present study, we experimentally manipulated both the visual field (the central and peripheral visual fields) and the occurrence of optical flow during quiet standing, examining the effects of the visual field and optical flow on postural sway measured in terms of the center of pressure (CoP). Stationary random dot stimuli were presented exclusively in either the central or peripheral visual field, while the occurrence of optical flow was manipulated using a desktop (DTD) or a head-mounted (HMD) display. The optical flow that occurred while using the DTD was a function of the postural sway during quiet standing, while for the HMD, no optical flow occurred even when the body/head swayed during quiet standing. Our results show that the extent of postural sway (e.g., CoP area) was smaller when visual stimuli were presented in the peripheral visual field than that in the central visual field; this was the case while using the DTD alone, with no effects of the peripheral vision on the extent of postural sway while using the HMD. It is therefore suggested that the optical flow occurring in the peripheral visual field is essential for stable quiet standing