Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 4125. Adviser: Christopher Wickens. Includes bibliographical references (leaves 71-76) Available on microfilm from Pro Quest Information and Learning.

Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 4128. Adviser: Ranxiao Frances Wang. Includes bibliographical references (leaves 68-70) Available on microfilm from Pro Quest Information and Learning.

Each day, we interact with and make judgments about objects we see in the visual field. These interactions depend on the perceptual segmentation of figure from ground, and the subsequent processing of the segmented representations. In order to survive in our increasingly complex world, it is not enough to know what is object and what is background; we must be able to rapidly infer information about sets of objects, such as their identity, in what direction are they moving, and how many are there. Parallel individuation is the rapid selection of multiple targets for precise and rapid processing. One of the hallmarks of parallel individuation behavior is the ability to re- port the number of items in small sets with extreme speed and accuracy; this behavior is called ‘subitizing’. Previous research has suggested that subitizing, and other tasks de- pendent on parallel individuation, rely on targets that are spatially separate from each other: objects rather than object parts. In this thesis, we explored what visual features, like connectivity, interfere with or are necessary for parallel individuation to occur. We first demonstrated that both connected and unconnected targets can be subitized. In order to ensure the same neural mechanism was responsible for the behavior ob- served in both stimulus conditions, we used functional magnetic resonance imaging to compare the neural responses to connected and unconnected stimuli. We targeted two regions in the parietal lobe, the inferior and superior intraparietal sulci, which have been previously associated with individuation and identification, respectively. Activity in both regions was modulated by the numerosity of targets in the connected and un- connected conditions. While multi-voxel pattern analyses revealed that the two regions additionally held representations of number, only the inferior IPS could discriminate connected from unconnected stimuli. We concluded from these results that individuation in the inferior IPS does not depend on spatially separate targets, but rather can flexibly select a level from the object hierarchy of a scene within which to define figure and ground. We then investigated the role of other visual features in parallel individuation, working from a condition of failure to pinpoint visual characteristics that are necessary for subitizing to occur. Resolving line ownership, providing unique centers of mass, and removing bounding enclosure information all did not prove sufficient for subitizing to occur in concentrically arranged squares. Changing the arrangement of the squares in space however did demonstrate that subitizing occurs over overlap- ping targets, with no effect of amount of overlap. Manipulating the presentation time of overlapping targets showed that parallel individuation can operate over both unresolved and completed amodal representations of a scene. We proposed that successful parallel individuation is dependent upon the constraints of three stages of processing: segmentation, individuation, and task specific demands. We suggest that the individuation stage is dependent upon each target occupying a unique location in space, occurring outside the border of all other targets. Finally we discussed the generalization of this model to other tasks involving parallel individuation. / Psychology

The purpose of this study was to gain a better understanding of the relationship between selected independent variables (gender and skill) and mental skills of athletes (goal-setting, self-confidence, commitment, imagery, mental practice, focusing, refocusing, competition planning, activation, relaxation, stress and fear control). The Ottawa Mental Skills Assessment Tool (OMSAT-3*) was administered to a sample of 249 (121 males and 128 females) athletes aged 14 to 19 who participated in sport at either a developing or provincial level in a variety of sports. A gender by skill (2 x 2) MANOVA resulted in a main effect (p < .004) for skill on the goal-setting, commitment, competition planning, focus, and refocus scales, as well as for foundation, cognitive, and psychosomatic skills components: The results imply there were no gender differences in athletes' level and use of mental skills.

Event-related potentials (ERPs) were recorded during sleep onset and various stages of sleep. A late component of the ERP, P300, is elicited when subjects detect a rare "target" stimulus. It is usually not elicited when subjects fail to detect the stimulus. The presence of P300 has therefore been used to index the extent to which the sleeper is aware of their external environment. During the transition to sleep, subjects were asked to detect a rare 2000 Hz target occurring among a train of 1000 Hz standards. A parietal maximum P300 was apparent in wakefulness, and remained large to detected targets in stage 1 sleep. It was however attenuated at frontal sites in stage 1. There were few detections in stage 2 and P300 was not evident. ERPs were then recorded within sleep. Very loud stimuli were employed since loud deviants will elicit an obligatory P300 response in waking-ignore conditions. In Experiment 2, 90 dB SPL tone pips were delivered on 5% of trials and 70 dB SPL tones on remaining trials. A large parieto-central positive wave was recorded in REM sleep. In non-REM sleep, a later and more occipital positivity was observed. It remained unclear whether the REM P300 was due to the rareness or the loudness of the deviant. In Experiment 3, various intensities (0, 60, 80, 100 dB SPL) were therefore delivered at equal probability (p = .25). A parietal maximum P300 was again recorded in REM following the 100 dB tone, but was not apparent following the lower intensities. A frontal P300 was not apparent following the loud stimulus. In Experiment 4, pitch- and intensity-deviants were investigated during sleep and wakefulness (attend and ignore conditions). In three separate groups, the rare stimulus was delivered on either 20%, 10% or 5% of trials. The pitch-deviant did not elicit P300 in any condition. In the waking-ignore condition, the intensity-deviant elicited a parietal maximum P300 that extended into the frontal region. A large REM-specific P300 was apparent at parietal sites following the intensity-deviant when stimuli were delivered on 5% of trials, but was not apparent at frontal sites. These studies illustrate that P300 can be recorded during sleep onset and during REM sleep. Only stimuli which are sufficiently intrusive and rare will elicit the parietal P300 in REM. While subjects may be able to detect stimulus deviance in stage 1 and REM, the frontal contribution to consciousness may be absent.

In 1996, Roussy et al. reported a study which failed to demonstrate the predictability of REM dream content from presleep ideation. The current study was designed to further test this predictability by using a larger sample of REM dream content and waking ideation. Thirteen young-adult female university students reported three REM dreams on each of four laboratory nights spaced at weekly intervals. On two of the study days, waking Thought Samples (TS) were recorded by participants at five randomly selected times. On the two other days, participants recorded their five most Significant Concerns (SC) prior to going to sleep at the laboratory. In a within-participant ranking task, two student peers had to read each item which consisted of the waking ideation sample for one night (WI) for one participant and the four dream sets (DS) for this same participant. Their task for each of these items was to rank the 4 DS from 1 to 4 as they believed them to be most likely related to the WI (rank 1) or least likely related to the WI (rank 4). For this task, there were two items for each of 12 participants. It was hypothesized that a dream set would receive a rank closer to 1 when it was the target than when it served as a foil. In a within-participant matching task, ten student peers were given the 4 dream sets and 4 waking ideation samples separately for each participant. Judges were asked to match each DS with one of the WI, thus making 4 pairs. In the between-participant matching task, these same ten judges were given 12 items. For each item, they were asked to match 4 dream sets from different participants with their corresponding waking ideation samples. For the ranking task, a three-way mixed ANOVA (2 judges - between, 2 waking ideation conditions: TS & SC - within, 2 dream conditions: target & nontarget - within) revealed that there were no significant differences between ranks given to target or foil dreams, and this in both the TS and SC conditions, as well as by both judges. Chi-square values for both the within- and between-participant matching task were not significant (.047 and .096 respectively, p < .99). The observed number of matches was therefore not significantly different from what was expected by chance. These results are consistent with those of our earlier study and suggest that it is not possible for non-clinically trained judges to match REM dream content with waking ideation. Further analyses conducted with a clinical psychologist serving as judge demonstrated that she was also unable to complete the tasks at greater than chance levels. It therefore seems that the relationship between waking and dreaming is not as obvious and predictable as has been believed. Rather, this study supports the cognitive position that dreams appear to randomly integrate elements from waking life and do not seem to give priority to immediately preceding experiences and concerns.

The purpose of this thesis research was to investigate the decision making of rugby referees. Based on past research, concepts felt to be important in this task were anticipation, and knowledge base. To investigate these features for referees, the expertise paradigm was incorporated. Thus, 12 high and 12 low experience referees were asked to evaluate clips of videotaped rugby footage for infractions. Participants were asked to anticipate upcoming actions and calls, and their ability to detect infractions was measured along with voice reaction time (VRT). In addition, referees were asked questions related to their knowledge bases, and the information sources from which they drew in performing this task. The responses to the videotaped plays were analysed using signal detection theory (Macmillan & Creelman, 1991) and revealed no significant group differences. Further, a two-way analysis of variance performed using the information sources data revealed significant differences between the high and low experience referee groups. Further sections discuss data collected on anticipation, VRT, and another measure of knowledge, that were eventually eliminated from the study. This and other related features led to a final section describing common characteristics and defining characteristics for the general population of sport monitors.

This program of research sought an answer to the following question: What is the nature of the mechanism underlying French readers' ability to identify syllabic boundaries in print? Two complementary approaches were taken to shed some light on this problem: first, we examined how the structural properties of syllables influence syllabification decisions; and second, we explored the relationship between syllabic structure and the issue of syllabic mediation in visual word recognition (VWR). In the first study, university students were asked to syllabify a list of 248 words (Experiment 1) or pseudowords (Experiment 2), in a paper-and-pencil syllabification task. The data were coded and then analyzed according to a framework representing the realm of all possible environments in which syllabic boundaries can be identified, within any given letter string. In the second study, participants were asked to verify the proper location for a syllabic boundary marker, which was inserted between the letters of isolated words displayed at the center of a computer screen (e.g., 'ca/bane' [shack]). In the syllable boundary verification (SBV) task, trisyllabic stimuli that contained a single medial consonant or medial consonant pair were contrasted either at the first or second syllabic boundary (i.e., Experiments 1 and 3: CV.C&barbelow;V.CV vs. CV C.CV.CV; Experiment 2: CV.CV.C&barbelow;V vs. CV.CV C.CV). The results showed that lexicality was not a factor in the untimed syllabification task (Study 1), where participants relied on simple heuristics to parse letter strings (i.e., spelling-to-sound translation, prescribed rule for separating geminate consonants). In the timed verification task (Study 2), a location-specific effect of syllabic structure was observed in the critical marker position for all three experiments, in addition to a word-frequency effect. Moreover, a reliable effect of marker serial position revealed an increase in response times towards the end of words. The pattern of results for this series of experiments is most consistent with the idea of a lexically-derived syllabic structure effect and inconsistent with one form of the syllabic mediation hypothesis (i.e., syllable-as-access-code hypothesis). Overall, the findings of both studies converge towards the following conclusion: The mechanism underlying the ability to identify syllabic boundaries in French print relies on multiple sources of constraint that vary according to task demands.

Expectations for performance, such as an expectation set by within team order in gymnastics (Scheer & Ansorge, 1975; 1980), have been shown to create a non-performance bias in terms of sport performance evaluation. Plessner (1999) found such a bias to influence both the encoding and evaluation phases of gymnastics judgement. In the sport of figure skating, the encoding phase is considered the period during which a judge perceives elements and any errors that may occur. After the performance is complete, judges evaluate the merit of the performance by providing two marks that are combined to create an ordinal rank, which is considered the evaluation phase of judging. The current study investigated whether or not expectations created by the reputation, or name, of an athlete occurs in the sport of figure skating, and if so, in what phase of the process, encoding or evaluation. Fourteen female figure skaters' short programs were viewed by judges to whom the athletes were either known or unknown. Judges were asked to provide technical base marks, technical merit, and artistic impression marks (all indicative of the evaluation phase), as well as to identify the elements and associated deductions (the encoding phase variables). Post-experiment, the ordinal placements of the skaters were calculated and used to define whether biases do exist at a basic level. Indeed, the skaters' average ordinal placement was higher when they were known by the judge as compared to unknown (t = 2.43, p < .05). A more in-depth analysis revealed that skaters received higher technical merit and artistic impression marks, as well as technical base marks when known to the judges. No significant differences, however, were found for deductions allocated for errors or for the judges' percent correctness in perceiving the elements performed. Thus, the findings suggest that a reputation bias exists at the level of the evaluation phase, but not during the encoding phase, of figure skating judging.

The relation between speed of auditory discrimination and intelligence was investigated. Thirty-six females in experiment 1 and 24 in experiment 2 completed the Multidimensional Aptitude Battery (MAB; Jackson, 1984). Subjects were divided into higher (HA) and lower (LA) ability groups. An auditory oddball paradigm was employed, with the addition of a masking stimulus (1000 Hz, 55ms duration) following the standard (600 Hz, 25 ms) and deviant (700 Hz, 25 ms) tones. The interval between standard or deviant offset and masking tone onset, the stimulus onset asynchrony (SOA), was varied at 150, 50 and 25 ms. The auditory discrimination task was presented in a passive condition in which participants ignored the tones while reading a book and in an active condition wherein they detected the deviant tone. The passive condition generated the mismatch negativity (MMN), an event-related potential measure that indexes the operation of echoic memory. The active condition produced behavioural data and P3, an ERP measure associated with stimulus evaluation and classification. In both experiments, HA participants detected more deviant tones, and had faster and less variable reaction times. Overall, P3 amplitude was significantly larger for HA subjects, with some differences in P3 latency observed. The HA group bad larger MMN amplitude in the first study only; shorter MMN latencies for the HA group were observed in study 2 only. An intensity manipulation in experiment 2, intended to manipulate task difficulty, produced no graded changes in any of the variables. Results for both experiments were combined to increase power and facilitate interpretation. Overall, results indicate that more intelligent individuals process information in short-term memory more rapidly than those of lower-ability; results also suggest that speed of processing in echoic memory may underlie ability-related differences in performance.