When viewing a face, healthy individuals tend to fixate on upper regions, particularly the eyes, which provide important configural information about the spatial layout of the face. In contrast, individuals with face blindness (prosopagnosia) rely more on local features – particularly the mouth. Presented here is an examination of face perception deficits in individuals with Posterior Cortical Atrophy (PCA). PCA is a rare progressive neurodegenerative disorder that is characterized by atrophy in occipito-parietal and occipito-temporal areas. PCA primarily affects higher visual processing, while memory, reasoning, and insight remain relatively intact. Common among individuals with PCA is simultanagnosia, an inability to perceive more than one object or detail simultaneously. One might consider simultanagnosia the most extreme form of a feature-based approach. In a series of investigations, individuals with PCA and their healthy control participants completed a same/different discrimination task in which images of faces were presented as cue-target pairs. Eye-tracking equipment (Experiment 1) and the newly developed Viewing window paradigm (Experiment 2) were used to investigate scanning patterns when faces were presented in full view, and through a restricted viewing aperture, respectively. In contrast to previous prosopagnosia research, individuals with PCA each produced unique scan paths that focused on one aspect of the face. Individuals with PCA tended to focus on areas of high-contrast but many of these areas were not diagnostically useful, suggesting that they were having difficulty processing the face even at a featural level. These results suggest a role of simultanagnosia in the scan patterns of PCA patients that is not reflective of ‘typical’ prosopagnosia, and instead points to simultanagnosia, sometimes matched with basic perceptual impairments, as a significant contributor to the face perception deficits seen in PCA.

Park and resource management agencies are looking for less costly ways to undertake park visitor surveys. The use of the Internet is often suggested as a way to reduce the costs of these surveys. By itself, however, the use of the Internet for park visitor surveys faces a number of methodological challenges that include the potential for coverage error, sampling difficulties and nonresponse error. A potential way of addressing these challenges is the use of a mixed-mode approach that combines the use of the Internet with another survey mode. The procedures for such a mixed-mode approach, however, have not been fully developed and evaluated. This study develops and evaluates a new mixed-mode approach –a face-to-face/web response – for a provincial park camper survey in British Columbia. The five key steps of this approach are: (a) selecting a random sample of occupied campsites; (b) undertaking a short interview with potential respondents; (c) obtaining an email address at the end of the interview; (d) distributing a postcard to potential respondents that contains the website and an individual access code; and (e) undertaking email follow-ups with nonrespondents. In evaluating this new approach, two experiments were conducted during the summer of 2010. The first experiment was conducted at Goldstream Provincial Park campground and was designed to compare a face-to-face/paper response to face-to-face/web response for several sources of survey errors and costs. The second experiment was conducted at 12 provincial park campgrounds throughout British Columbia and was designed to examine the potential for coverage error and the effect of a number of email follow-ups on return rates, nonresponse error and the substantive results. Taken together, these experiments indicate: a low potential for coverage error (i.e., 4% non-use Internet rate); a high email collection rate for follow-ups (i.e., 99% at Goldstream; a combined rate of 88% for 12 campgrounds); similar return rates between a paper mode (60%) and a web (59%) mode; the use of two email follow-ups reduced nonresponse error for a key variable (i.e., geographic location of residence), but not for all variables; low item nonresponse for both mixed-modes (about 1%); very few differences in the substantive results between each follow-up; a 9% cost saving for the web mode. This study suggests that a face-to face/web approach can provide a viable approach for undertaking park visitor surveys if there is high Internet coverage among park visitors. / Graduate / 0366 / 0344 / 0814 / brdyckfam@yahoo.com

No description available.

This thesis explores the effects of movement on various face processing tasks. In Experiments One to Four, unfamiliar face recognition was investigated using identical numbers of frames in the learning phase; these were viewed as a series of static images, or in moving sequences (using computer animation). There was no additional benefit from studying the moving sequences, but signal detection measurements showed an advantage for using dynamic sequences at test. In Experiments Five and Six, moving and static images of unfamiliar faces were matched for expression or identity. Without prior study, movement only helped in matching the expression. It was proposed that motion provided more effective access to a stored representation of an emotional expression. Brief familiarisation with the faces led to an advantage for dynamic presentations in referring to a stored representation of identity as well as expression. Experiments Seven to Nine explored the suggestion that motion is beneficial when accessinga pre-existingd escription. Significantly more famous faces were recognised in inverted and negated formats when shown in dynamic clips, compared with recognition using static images. This benefit may be through detecting idiosyncratic gesture patterns at test, or extracting spatial and temporal relationships which overlapped the stored kinematic details. Finally, unfamiliar faces were studied as moving or static images; recognition was tested under dynamic or fixed conditions using inverted or negated formats. As there was no difference between moving and static study phases, it was unlikely that idiosyncratic gesture patterns were being detected, so the significant advantage for motion at test seemed due to an overlap with the stored description. However, complex interactions were found, and participants demonstrated bias when viewing motion at test. Future work utilising dynamic image-manipulated displays needs to be undertaken before we fully understand the processing of facial movement.

No description available.

This thesis addresses analysis, evaluation and simulation of low complexity face detection algorithms and tracking that could be used on mobile phones. Network access control using face recognition increases the user-friendliness in human-computer interaction. In order to realize a real time system implemented on handheld devices with low computing power, low complexity algorithms for face detection and face tracking are implemented. Skin color detection algorithms and face matching have low implementation complexity suitable for authentication of cellular network services. Novel approaches for reducing the complexities of these algorithms and fast implementation are introduced in this thesis. This includes a fast algorithm for face detection in video sequences, using a skin color model in the HSV (Hue-Saturation-Value) color space. It is combined with a Gaussian model of the H and S statistics and adaptive thresholds. These algorithms permit segmentation and detection of multiple faces in thumbnail images. Furthermore we evaluate and compare our results with those of a method implemented in the Chromatic Color space (YCbCr). We also test our test data on face detection method using Convolutional Neural Network architecture to study the suitability of using other approaches besides skin color as the basic feature for face detection. Finally, face tracking is done in 2D color video streams using HSV as the histogram color space. The program is used to compute 3D trajectories for a remote surveillance system.

Current models of face perception suggest independent processing of identity and expression, though this distinction is still unclear. Using converging methods of psychophysics and functional magnetic resonance imaging (fMRI) in healthy and patient populations we assessed the relationship between these two perceptual processes. First, using perceptual aftereffects, we explored the neural representations underlying identity and expression. The expression aftereffect only partially transferred across different identities, suggesting adaptation within identity-invariant and identity-dependent expression representations. Contrarily, the identity aftereffect fully transferred across different expressions. This asymmetry cannot be explained through low-level adaptation. The identity-dependent component of the expression aftereffect relies on adaptation to a coherent expression, not low-level features, in the adapting face. Thus adaptation generating the expression aftereffect must occur within high-level representations of facial expression. Second, using fMRI adaptation, we examined identity and expression sensitivity in healthy controls. The fusiform face area and posterior superior temporal sulcus showed sensitivity for both identity and expression changes. Independent sensitivity for identity and expression changes was observed in the precuneus and middle superior temporal sulcus respectively. Finally, we explored identity and expression perception in a neuropsychological population. Selective identity impairments were associated with inferior occipitotemporal damage, not necessarily affecting the occipital or fusiform face areas. Impaired expression perception was associated with superior temporal sulcus damage, and also with deficits in the integration of identity and expression. In summary, psychophysics, neuroimaging and neuropsychological methods all provide converging evidence for the independent processing of identity and expression within the face network. However, these same methods also supply converging evidence for a partial dependence of these two perceptual processes: in the expression aftereffect, the functional sensitivities of the FFA and pSTS, and identity deficits observed in a patient with primarily impaired expression perception and a spared inferotemporal cortex. Thus, future models of face perception must incorporate representations or regions which independently process identity or expression as well as those which are involved in the perception of both identity and expression.

This thesis is an effort to apply Elias’s thinking on social development to the Chinese social situation. At first glance his account of the civilizing process would appear incompatible with this context, in that, after state formation with the Qin and Han dynasties beginning in 221 BC, Chinese civilization remained both stable and highly traditional for well over two millennia. It is argued, however, that closer scrutiny reveals a process that was merely interrupted for a considerable period. The traditional system relied upon a symbiotic relationship between local society and the centre whereby the centre remained relatively small and aloof, not interfering with local social relations, as long as local society provided the required taxes and labour. In this situation the state had the monopolies of both violence and taxation that Elias would look for, but left local society to its own devices primarily because it was already pacified. This self-reinforcing system was enshrined and codified in the Confucian cannon over the course of centuries from the Han dynasty. Central control of the distribution of resources was eventually required to re-start the Chinese civilizing process, for this was the mechanism through which the local social structure would finally be altered. This only happened within the past century as the Chinese people struggled to grapple with their own ‘backwardness’ in the face of incessant Western and Japanese incursions. At this point the old system was toppled and replaced by progressively more aggressive central governments who saw as their most important task the destruction of the traditional social order in the interest of modernization. As the Chinese state consciously and forcibly took control of the distribution of resources at all levels of society, traditional social relations were stretched and warped, and the Chinese civilizing process re-commenced its long-stalled march toward modernization. This has been evidenced both by the dramatic growth in mobility and the rapidly extending chains of interdependence in the form of guanxi connections primarily during the Post-Opening period after 1978.

This hermeneutical study interprets and describes the phenomena of ageing and living with disability. The lived experiences of 14 older men and the horizon of this researcher developed an understanding of what it is like for men to grow old and, for some, to live with the effects of a major disability. The study is grounded in the philosophical hermeneutics of Gadamer and framed in the context of embodiment, masculinity, and narrative. I conducted multiple in-depth interviews with older men aged from 67 to 83 years of age. Seven of the participants had experienced a stroke and I was able to explore the phenomenon of disability with them. Through thematic and narrative analyses of the textual data interpretations were developed that identified common meanings and understandings of the phenomena of ageing and disability. These themes and narratives reveal that the men�s understandings are at odds with conventional negative views of ageing and disability. These older men are �alive and kicking�, they voice counternarratives to the dominant construction of ageing as decline and weakness, and have succeeded in remaking the lifeworld after stroke. Overall I have come to understand an overarching meaning of older men �working it out� as illustrative of a strong face of ageing and disability. Older men seek out opportunities to participate actively in community life and, despite the challenges of ageing and disability, lead significant and meaningful lives. These findings challenge and extend our limited understandings of men�s experiences of ageing and living with disability. This interpretation offers gendered directions for policy development, clinical practice, and future research.

Thesis (M.S.)--Youngstown State University, 2007. / Includes bibliographical references (leaves 24-28).