Our eyes are horizontally separated in the head by approximately 6.5cm. As a result of this separation there are subtle differences in the position of corresponding image points within the two eyes. The horizontal component of this binocular positional difference is termed horizontal disparity. Horizontal disparity is an important visual cue as once scaled with an estimate of the viewing distance, it can theoretically provide full metric information about the structure of the world. This thesis will address the issue of how binocular visual cues are used by the human visual system for the estimation of three-dimensional (3-D) shape for perception and visuomotor control. The research presented is particularly focused on understanding why biases in the perception of 3-D shape from binocular cues are found, their importance for perception and visuomotor control and how these biases may be overcome by combining binocular cues with other sources of visual information.

This study investigates the use of response guidance for errorless learning of a perceptual motor task in normal elderly. It provides normative data for a study with stroke patients using this technique for cognitive rehabilitation. While errorless learning has been shown to be more effective on most tasks than trial and error learning for people with memory impairments, its use with normal individuals has received limited attention. The questions of interest were whether errorless training of the perceptual motor task was more effective for improving and retaining accuracy; and whether both accuracy and response speed were more resistant to the effects of increased cognitive demands. A sample of 43 normal elderly in the United Kingdom, ranging in age from 60 to 77, completed an assessment of intelligence, memory, and attention. They then received training, over two sessions one week apart, to mark the midpoint of Judd Arrows presented on a computer screen using a cross cursor moved by an active force feedback joystick (AFF). During training the errorless group received AFF guidance to the correct midpoint, while the errorful group received none, and both received auditory and visual knowledge of results. There was no AFF during baseline or post test measures. Training was to criterion in each session with a discontinue rule if accuracy did not improve. At the end of session two both groups were given a cognitively challenging task concurrent with the arrow bisection. Results revealed that both groups improved their accuracy through training with the errorless group being significantly more accurate and tending to be faster in the final post tests of both sessions. The errorless group was significantly faster than the errorful group under the cognitive challenge, without sacrificing accuracy. These results suggest not only that AFF is an effective means of implementing errorless perceptual motor learning, but elderly individuals trained in this manner do not sacrifice accuracy for speed. Implications of these results are discussed.

This investigation examined the development of young children's behaviors on swings in the outdoor play environment and their emerging understanding of the physics principles associated with those behaviors. The children's language interactions were also examined in an effort to determine the relationship between language and cognitive development in their construction of physical knowledge. The procedures involved observing the children's behaviors and collecting samples of their spontaneous language interactions during their swinging activities. Informal interviews were also conducted with individual and groups of children. The findings indicate that young children's swinging behaviors develop in eight hierarchical stages. As these behaviors develop, children experiment with the physics principles of balance, gravity, force, resistance, and resonance. Children's swinging behaviors develop in a social context. Many early behaviors are acquired through observing and modeling other children. Language provides the medium for more-experienced peers to assist novice swingers through encouragement and direct instruction. The stage development of swinging behaviors is compared to Cratty's Theory of Perceptual-Motor Development and Harrow's Taxonomy of the Psychomotor Domain. Children's cognitive processing and language interactions are discussed in the context of Piagetian and Vygotskian theories of development. Implications for instruction and suggestions for further research are discussed.

I investigated how two types of rhythmic complexity, syncopation and tempo fluctuation, affect the neural and behavioral responses of listeners. The aim of Experiment 1 was to explore the role of attention in pulse and meter perception using complex rhythms. A selective attention paradigm was used in which participants attended either to a complex auditory rhythm or a visually presented list of words. Performance on a reproduction task was used to gauge whether participants were attending to the appropriate stimulus. Selective attention to rhythms led to increased BOLD (Blood Oxygen Level-Dependent) responses in basal ganglia, and basal ganglia activity was observed only after the rhythms had cycled enough times for a stable pulse percept to develop. These observations show that attention is needed to recruit motor activations associated with the perception of pulse in complex rhythms. Moreover, attention to the auditory stimulus enhanced activity in an attentional sensory network including primary auditory, insula, anterior cingulate, and prefrontal cortex, and suppressed activity in sensory areas associated with attending to the visual stimulus. In Experiment 2, the effect of tempo fluctuation in expressive music on emotional responding in musically experienced and inexperienced listeners was investigated. Participants listened to a skilled music performance, including natural fluctuations in timing and sound intensity that musicians use to evoke emotional responses, and a mechanical performance of the same piece, that served as a control. Participants reported emotional responses on a 2-dimensional rating scale (arousal and valence), before and after fMRI scanning. During fMRI scanning, participants listened without reporting emotional responses. Tempo fluctuations predicted emotional arousal ratings for all listeners. / Expressive performance was associated with BOLD increases in limbic areas for all listeners and in limbic and reward related areas forthose with musical experience. Activity in the dorsal anterior cingulate, which may reflect temporal expectancy, was also dependent on the musical experience of the listener. Changes in tempo correlated with activity in a mirror neuron network in all listeners, and mirror neuron activity was associated with emotional arousal in experienced listeners. These results suggest that emotional responding to music occurs through an empathic motor resonance. / by Heather L. Chapin. / Thesis (Ph.D.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

This dissertation investigated the nature of pulse in the tempo fluctuation of music performance and how people entrain with these performed musical rhythms. In Experiment 1, one skilled pianist performed four compositions with natural tempo fluctuation. The changes in tempo showed long-range correlation and fractal (1/f) scaling for all four performances. To determine whether the finding of 1/f structure would generalize to other pianists, musical styles, and performance practices, fractal analyses were conducted on a large database of piano performances in Experiment 3. Analyses revealed signicant long-range serial correlations in 96% of the performances. Analysis showed that the degree of fractal structure depended on piece, suggesting that there is something in the composition's musical structure which causes pianists' tempo fluctuations to have a similar degree of fractal structure. Thus, musical tempo fluctuations exhibit long-range correlations and fractal scaling. To examine how people entrain to these temporal fluctuations, a series of behavioral experiments were conducted where subjects were asked to tap the pulse (beat) to temporally fluctuating stimuli. The stimuli for Experiment 2 were musical performances from Experiment 1, with mechanical versions serving as controls. Subjects entrained to all stimuli at two metrical levels, and predicted the tempo fluctuations observed in Experiment 1. Fractal analyses showed that the fractal structure of the stimuli was reected in the inter-tap intervals, suggesting a possible relationship between fractal tempo scaling, pulse perception, and entrainment. Experiments 4-7 investigated the extent to which people use long-range correlation and fractal scaling to predict tempo fluctuations in fluctuating rhythmic sequences. / Both natural and synthetic long-range correlations enabled prediction, as well as shuffled versions which contained no long-term fluctuations. Fractal structure of the stimuli was again in the inter-tap intervals, with persistence for the fractal stimuli, and antipersistence for the shuffled stimuli. 1/f temporal structure is suficient though not necessary for prediction of fluctuations in a stimulus with large temporal fluctuations. / by Summer K. Rankin. / Vita. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Since students can adjust the speed of online videos by time-compression which is available through common software (Pastore & Ritzhaupt, 2015), it is important to learn at which point compression impacts comprehension. The focus of the study is whether the speaker’s face benefits comprehension during a 50% compressed lecture. Participants listened to a normal lecture or a 50% compressed lecture. Each participant saw an audio and audiovisual lecture, and were eye tracked during the audiovisual lecture. A comprehension test revealed that participants in the compressed lecture group performed better with the face. Eye fixations revealed that participants in the compressed lecture group looked less at the eyes and more at the nose when compared to eye fixations for those that viewed the normal lecture. This study demonstrates that 50% compression affects eye fixations and that the face benefits the listener, but this much compression will still lessen comprehension. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

Traditionally brain function is studied through measuring physiological responses in controlled sensory, motor, and cognitive paradigms. However, even at rest, in the absence of overt goal-directed behavior, collections of cortical regions consistently show temporally coherent activity. In humans, these resting state networks have been shown to greatly overlap with functional architectures present during consciously directed activity, which motivates the interpretation of rest activity as day dreaming, free association, stream of consciousness, and inner rehearsal. In monkeys, it has been shown though that similar coherent fluctuations are present during deep anesthesia when there is no consciousness. These coherent fluctuations have also been characterized on multiple temporal scales ranging from the fast frequency regimes, 1-100 Hz, commonly observed in EEG and MEG recordings, to the ultra-slow regimes, < 0.1 Hz, observed in the Blood Oxygen Level Dependent (BOLD) signal of functi onal magnetic resonance imaging (fMRI). However, the mechanism for their genesis and the origin of the ultra-slow frequency oscillations has not been well understood. Here, we show that comparable resting state networks emerge from a stability analysis of the network dynamics using biologically realistic primate brain connectivity, although anatomical information alone does not identify the network. We specifically demonstrate that noise and time delays via propagation along connecting fibres are essential for the emergence of the coherent fluctuations of the default network. The combination of anatomical structure and time delays creates a spacetime structure in which the neural noise enables the brain to explore various functional configurations representing its dynamic repertoire. / Using a simplified network model comprised of 3 nodes governed by the dynamics of FitzHugh-Nagumo (FHN) oscillators, we systematically study the role of time delay and coupling strength in the Using a simplified network model comprised of 3 nodes governed by the dynamics of FitzHugh-Nagumo (FHN) oscillators, we systematically study the role of time delay and coupling strength in the generation o f the slow coherent fluctuations. We find that these fluctuations in the BOLD signal are significantly correlated with the level of neural synchrony implicating that transient interareal synchronizations are the mechanism causing the emergence of the ultra slow coherent fluctuations in the BOLD signal. / by Young-Ah Rho. / Thesis (Ph.D.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

Visual motion can be conveyed by a variety of information sources in the environment, and those types of information may be detected at various levels by different motion-perceiving mechanisms in the visual system. High-level visual information has been demonstrated to have 3rd order, or salience-based properties (Lu & Sperling, 1995). The perceptual system they describe that computes motion from these types of information shares several characteristics with Hock and colleagues' counterchange detection system, notably flexibility with respect to types of input from which motion can be computed, which comes at the cost of diminished processing speed. The mechanism of counterchange detection is well suited to processing visual features often present in environmental scenes, e.g., objects and surfaces, and may be a mechanism of 3rd order motion. Consistent with reported properties of 3rd order motion, the current experiments tested count erchange-, luminance-, and color-based motion stimuli with 3 objectives: to identify whether the 3 systems framework generalizes beyond the stimulus type with which it was defined, to test whether counterchange shares similarities with the 3rd order system with respect to dichoptic integration, and perception of isoluminant color-based motion, and to test subjectively objectless sources of motion-defining information (spreading luminance and hue) to see if they display properties of the 1st order system derived from sine wave gratings. Results indicate that counterchange-based stimuli displayed predicted properties of dichoptic integration, and perception at isoluminance, but putative 1st order (spreading) stimuli also displayed these properties. This may suggest that object-like surfaces, even when not directly the source of motion information, can contribute to computation of motion. Further, these results highlight the difficulty of generalizing from one theoretical framework to another, and specifically, of psychophysically testing high-level information while isolating contributions from low level information upon which high level visual stimuli are built. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection

Prior research has explored the counterchange model of motion detection in terms of counterchanging information that originates in the stimulus foreground (or objects). These experiments explore counterchange apparent motion with regard to a new apparent motion stimulus where the necessary counterchanging information required for apparent motion is provided by altering the luminance of the background. It was found that apparent motion produced by background-counterchange requires longer frame durations and lower levels of average stimulus contrast compared to foreground-counterchange. Furthermore, inter-object distance does not influence apparent motion produced by background-counterchange to the degree it influences apparent motion produced by foreground-counterchange. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

We sought to better understand human motor control by investigating functional interactions between the Supplementary Motor Area (SMA), dorsal Anterior Cingulate Cortex (dACC), and primary motor cortex (M1) in healthy adolescent participants performing visually coordinated unimanual finger-movement and n-back working memory tasks. We discovered modulation of the SMA by the dACC by analysis of fMRI BOLD time series recorded from the three ROIs (SMA, dACC, and M1) in each participant. Two measures of functional interaction were used: undirected functional connectivity was measured using the Pearson product-moment correlation coefficient (PMCC), and directed functional connectivity was measured from linear autoregressive (AR) models. In the first project, task-specific modulation of the SMA by the dACC was discovered while subjects performed a coordinated unimanual finger-movement task, in which the finger movement was synchronized with an exogenous visual stimulus. In the second project, modulation of the SMA by the dACC was found to be significantly greater in the finger coordination task than in an n-back working memory, in which the same finger movement signified a motor response indicating a 0-back or 2-back working memory match. We thus demonstrated in the first study that the dACC sends task-specific directed signals to the supplementary motor area, suggesting a role for the dACC in top-down motor control. Finally, the second study revealed that these signals were significantly greater in the coordinated motor task than in the n-back working memory task, suggesting that the modulation of the SMA by the dACC was associated with sustained, continuous motor production and/or motor expectation, rather than with the motor movement itself. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection