The thesis is an account of an investigative study into the nature of perceptual-motor abilities. Part one considers Witkin's construct of cognitive style, using it to predict the relationships between three tests of perceptual functioning from widely varying areas of psychology and sports science. To some extent the results were as predicted; that is, those people demonstrating high levels of perceptual acuity on one test also showed similar acuity on one or more of the other perceptual tests. These results, however, only applied to the male subjects and then only when the opposite poles of one test-dimension were partitioned out and compared. The female subjects demonstrated no significant relationships between the three tests. As a result, it was proposed that the tests were indeed linked but by an array of underlying perceptual abilities rather than by a single, overlying cognitive or perceptual style. In the ensuing search for these abilities, 76 measures of perceptual and perceptual-motor skills were factor analysed to reveal 8 oblique perceptual-motor factors of which one was interpreted as being perceptual style. The nature of perceptual-motor abilities is discussed both in relation to clumsiness and to sports training with the emphasis being on whether such abilities are amenable to alteration. The thesis puts forward the proposal that an upper limit to each ability is fixed for each individual in early childhood but that this potential may be maximised through relevant training. The Perceptual-Motor Ability Profile was devised as a tool with which to indicate the aptitude a person evidenced for a particular sport or physical activity and was used in demonstration to describe the group abilities of four dancers with respect to the requirements of their chosen activity. Finally, a model of perceptual-motor functioning, relating the eight factors extracted, is suggested.

The mirror neuron system consists of a specific class of visuomotor neurons, which fire for both observation and execution of an action (di Pellegrino et al., 1992), as well as showing differences for empathy and gender. Fifty males (M = 25.94) and fifty females (M = 25.48) watched short clips of a hand tapping fingers in a sequence in neutral and emotional settings. Participants were asked to imitate emotions while watching and repeating the finger sequences. A univariate ANOVA discovered significant differences in response times for males and females in the emotion trials, which were eliminated when empathy was included in the analysis. Findings show those higher in empathy are faster at imitation of a motor task in emotional settings. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

No description available.

Discrimination thresholds were obtained during a delayed spatial frequency discrimination task. In Experiment 1, we found that presentation of a mask 3 s before onset of a reference Gabor patch caused selective interference in a subsequent discrimination task. However, a 10 s interval abolished this masking effect. In Experiment 2, the mask was associated with a second spatial frequency discrimination task so that a representation of the mask had to be coded into short-term perceptual memory. The presence of this second discrimination task now caused similar interference effects on the primary discrimination task at both the 3 s and 10 s ISI conditions. The different results from these two experiments are best explained by a two-step perceptual memory mechanism. The results also provide further insight into the conditions under which stimulus representations are shared between the perceptual and memory domains.

201 leaves : ill. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis -- University of Adelaide, Dept. of Psychology, 1967

The psychophysical experiments and numerical modelling reported in the present study are an investigation into the encoding of relative location of intensity changes in the human visual system. The study attempted, successfully, to explain some geometric illusions resulting from closely spaced image features ('crowding'), and determined the nature of information necessary for making judgments about the separation of intensity changes for different stimulus configurations. Experiments performed fell into two basic categories; those concerned with spatial interference, and studies of spatial interval judgments. The first set of experiments, studying spatial interference with relative localisation for intensity changes, was based on measurements made with stimuli composed of lowpass filtered bars and edges. The most successful model, which accounted for all of the data, was Watt and Morgan's (1984, 1985) MIRAGE; the results suggest that a good explanation of some geometric illusions can be derived using the principles of low-level vision. Spatial interference is strong evidence for combination of information across spatial scales, and the MIRAGE algorithm makes some highly accurate predictions. Relating the separation of image features is a fundamental task for the visual system, but there is no clear understanding of what information the system has available to perform this task. The second set of experiments explored the perception of separation, and precision of judgments of separation, for bars with a variety of orthoaxial contrast profiles. The data indicate that information is combined across spatial scales (as in MIRAGE) under certain circumstances in making separation judgments; this combination of information across scale occurs when the information on the scales combined is in agreement (ie. all scales have some task-related information), but when variance is added on coarser scales which is not relevant to the task, the system is capable of selecting the finest scales of filters available, and using only the information in the finest scale. This adaptive scale-selection process operates even at very brief exposure durations.

A series of studies is described here which explore the functional organisation of face- and object-processing neurones in the adult vervet monkey brain. This fundamental issue in high-level vision is addressed by the use of a novel molecular mapping technique that was developed for this purpose. / In the first study, the temporal dynamics of c-fos and zif268 expression were delineated in detail in the rat visual cortex. Knowing the precise temporal parameters of up-regulation (after onset of sensory stimulation) and down-regulation (after offset of sensory stimulation) of these genes was integral to optimising the temporal aspects of the stimuli to be used for subsequent mapping experiments. This study provided the critical information for devising stimuli with corresponding temporal parameters to those of c-fos or zif268 so that one could take advantage of the disparity between the expression of their mRNA and protein products in order to visualise activated neurones. / In the second study, the newly developed molecular mapping technique was validated in the rat auditory, visual and multisensory systems. First, bimodal audiovisual stimuli were designed using the data obtained from the first study. Then, through the combined histological detection of the mRNA and protein products of zif268, discrete populations of neurones responsive to either component of the bimodal stimulus were visualised. It was also observed that a third population of neurones was found that responded to the stimulation through both sensory modalities. The combined results from these two studies set the stage for addressing the issue of the organisation of face- and object-selective neurones of the inferior temporal cortex in the vervet monkey brain. / In the third study, the functional organisation of face- and object-selective neurones was examined using the molecular mapping technique. Based on the data gathered from the first two studies, suitable stimuli containing two distinct object classes (conspecific faces and non-face familiar objects) were designed with appropriate temporal parameters. / Finally, the last study provided an opportunity to address the issue of hemispheric asymmetry of function in the context of face processing in the non-human primate brain. Results support the notion that there may indeed be phylogenetic explanations for the hemispheric asymmetry observed in the human brain.

No description available.

Call number: LD2668 .T4 1986 D86 / Master of Science / Physical Education, Dance, and Leisure Studies

The hippocampus is necessary for normal memory in rodents, birds, monkeys, and people. Damage to the hippocampus can result in the inability to learn new facts, defined by the relationship among stimuli. In rodents, spatial learning involves learning about the relationships among stimuli, and exemplifies the kind of learning the requires the hippocampus. Therefore, understanding the neural mechanisms underlying spatial learning may elucidate basic memory processes. Many hippocampal neurons fire when behaving rats, cats, or monkeys are in circumscribed regions (place fields) of an environment. The neurons, called place cells, fire in relation to distal stimuli, but can persist in signaling location when the stimuli are removed or lights are turned off (memory fields). In this thesis, computational models of spatial information processing simulated many of the defining properties of hippocampal place cells, including memory fields. Furthermore, the models suggested a neurally plausible mechanism of goal directed spatial navigation which involved the encoding of distances in the connections between place cells. To navigate using memory fields, the models required an excitatory, distributed, and plastic association system among place cells. Such properties are well characterized in area CA3 of the hippocampus. In this thesis, a new electrophysiological study provides evidence that a second system in the dentate gyrus has similar properties. Thus, two circuits in the hippocampus meet the requirements of the models. Some predictions of the models were then tested in a single-unit recording experiment in behaving rats. Place fields were more likely to occur in information rich areas of the environment, and removal of single cues altered place fields in a way consistent with the distance encoding mechanism suggested by the models. It was concluded that a distance encoding theory of rat spatial navigation has much descriptive and predictive utility, but most of its predic