Visual perception of action categories and the "bowl-throw" decision in cricket.

Cricket umpires, cricket bowlers, and physical education students (who were knowledgeable about the rules of cricket), were shown 72 videotaped point-light displays of cricket deliveries with varying extents of elbow flexion such that they ranged from highly "bowl-like" to highly "throw-like". The observers made a bowl-throw decision about each display, and the umpires and bowlers reported their confidence on a 5-point scale. The percentage of displays reported as a "bowl" was 59, 40, and 44 for the umpires, bowlers, and students respectively. Umpires made significantly more bowl decisions than both the bowlers and students, but there was no difference between the latter groups. Umpires were significantly more confident than the bowlers in both their bowl and throw decisions. Thus, in an experimental setting, with no apparent costs or benefits associated with their decision-making, umpires "called" a bowler significantly less frequently for throwing than other knowledgeable observers. The procedures devised for this experiment demonstrate that psychophysical methods can be applied to the problem of discrete action-category nominations in sport (e.g., bowl or throw, walk or run).

Visual perception of human activity and gender in biological-motion displays by individuals with mental retardation.

By examining perception of biological-motion in three experiments, we investigated whether limitations in perceptual ability by individuals with mental retardation may extend to learning perceptual categories based on elements of actions. In two experiments individuals with mental retardation and age- and gender-matched controls reported gender and activity in randomly ordered point-light displays. In Experiment 2 decision times were measured and in Experiment 3, the effect of training with feedback on discriminating gender was assessed. Individuals with mental retardation identified walking, running, and stair-climbing without error but were less proficient in identifying throwing, had slower decision times for activity identification, and could not identify gender. For both groups feedback training improved gender identification in the short- and long-term. Improvements represented above-chance responding for the retarded group. Experimental outcomes are discussed in terms of capacity to classify perceptual stimuli as actions.

Recognition of facial emotional expressions from moving and static displays by individuals with mental retardation.

Moving and static videotaped and photographic displays of posed emotional expressions were presented to 12 adults with mental retardation and 12 without mental retardation to investigate the role of movement in the recognition of facial expressions of emotion. Participants chose the corresponding emotion portrayed by the displays from among six written and pictorial labels of the emotions. Results indicated that individuals with mental retardation were significantly poorer at identifying anger, fear, disgust, and surprise. Both groups performed significantly better on the moving as opposed to the static videotaped displays of the emotions sad and angry. Visual-perceptual limitations are likely contributors to the poorer performance of the group with mental retardation in recognizing moving and static facial expressions of emotion.

Visual discrimination and motor reproduction of movement by individuals with mental retardation.

Visual discrimination and motor reproduction tasks involving computer-simulated arm movements were administered to 12 adults with mental retardation and a gender-matched control group to examine whether inadequacies in visual perception account for the poorer motor performance of individuals with mental retardation. In the discrimination phase subjects judged whether simulated arm movements were either of greater or lesser extent or shorter or longer in duration, respectively, than those of a standard display. In the reproduction phase accuracy in reproducing the movement in the standard display was measured. Results indicate that error in discriminating extent and duration was significantly greater for the individuals with mental retardation, who were also less accurate and more variable in matching the extent and duration of the standard displays. These outcomes implicate both perceptual and motor-reproduction inadequacies in skill acquisition for these individuals.

Constraints on the participation of individuals with mental retardation in mainstream recreation.

A questionnaire was designed to investigate the influence of skill level, behavioral characteristics, and labeling upon attitudes toward the participation of individuals with mental retardation in a recreation activity. The respondents were 320 members of 12 private tennis clubs. High multiple correlations between the predictor variables, attitude toward the behavior, and subjective norm, with behavioral intention supported the model of the theory of reasoned action. Attitudes, subjective norms, and behavioral intentions toward individuals with mental retardation were favorable regardless of the label assigned and perceived skill level. Perceived behavior of the target person, rather than skill level and label, was the more salient influence upon attitudes, subjective norms, and behavioral intentions.

Intelligence and motor skill acquisition by discrimination learning.

This experiment investigated the relation between intelligence and acquisition of motor skill using predictions from Zeaman and House's 1963 attention theory. 20 undergraduate students and 20 subjects of low IQ (WAIS-R Full Scale IQ range 50 to 73, M = 60) made linear positioning movements of long and short amplitude to the left and right of a central starting position. Four conditions (right-long, right-short, left-long, left-short) were created by specifying the corresponding target area on the positioning apparatus. One or both of the paired cues were varied, i.e., left, right, long, or short, while the dimensions of direction and amplitude remained unchanged across conditions. A shift from one condition to the next followed a criterion response of four consecutive movements to the target area. Results supported the hypothesis that subjects of low IQ would require more trials to criterion than subjects of normal IQ across all conditions of direction and extent. There was qualified support for the hypothesised interaction between intelligence and cue shifts. The practical implications and theoretical significance of these findings are discussed.