The purpose of this investigation was to measure the ability of young normal hearing listeners to perceive speech in the presence of a background noise which varies in the relative intensity of its semantic content. The Speech Perception in Noise test was mixed with a two-component competing noise complex in which the narrative-to- speech noise ratio varied in 2 dB increments from -2 dB Na/SpN to +8 dB Na/SpN. These stimuli were presented at an overall +8 dB signal-to-noise ratio to thirty young normal hearing adults through the soundfield system. The differences between the mean error scores and standard deviations for the low predictability sentences were found to be statistically significant at all Na/SpN ratios. No main effect was observed for the Na/SpN ratios on the high predictability sentences. Significant differences were also observed between the mean error scores and standard deviations of HP and LP pairs at each Na/SpN ratio. These data further revealed a systematic increase in LP mean error scores and standard deviations as a result of linear increases in the Na/SpN ratio. These results suggest that semantically loaded competing noise significantly influences the perception of primary messages as a direct function of the competition ratio.

In a tachistoscopic perception task, adult males in the Fels Research Institute's longitudinal population (Kagan and Moss, 1960) were found to have a higher recognition threshold for pictures depicting dependency scenes than adult females. The female subjects had a higher recognition threshold for aggressive scenes than the males. The present study was designed to further compare male and female perception of dependent and aggressive stimuli by including a developmental component to test if the perceptual differences vary with age. A benign or neutral stimulus category was added to aid in determining direction of any resulting differences: i.e., heightened perception or avoidance of perception, and a recognition memory task was added to the tachistoscopic task to determine if there were any differences between sensory and long term memory of emotional stimuli.

The main purpose of this study was to examine the psychometric characteristics of the Bicycle Drawing Test. The 20-point scoring criterion was evaluated, and the preliminary norms were established. The Bicycle Drawing Test is an easily administered free-style drawing task that has been found to be a useful addition to a neuropsychological test battery. It provides a sample of visuopractic functioning involving the formation of a perceptual construct, a motor response, and a spatial component.

The question posed in this investigation was: Which stimulus input mode, verbal, pantomime, or combined verbal and pantomime, is more effective in facilitating short term sequential recall of language material with aphasic adults?

This study has two parts: Part I discusses the limitations of difference scores and exploratory factor analysis for representing speed of information-processing stages in the context of a reanalysis of a study by Vernon (1983). Vernon interpreted the differences between objectively measured reaction times on various simple cognitive tasks as components of speed of information processing. Correlations were calculated among these differences and subjected to exploratory factor analysis. The factors obtained from this analysis were interpreted by Vernon in terms of short-term and long-term memory processing constructs. The use of difference scores, however, implies an additive model allowance for random error, which correlations between these differences. that does not make leads to spurious The application of exploratory factor analysis to among these differences compounds uncover latent variables the problem because it admits many alternative interpretations which cannot be tested against one another for goodness-of-fit to the data. Confirmatory factor analysis addresses these problems. This thesis demonstrates that the correlations between the difference scores can be accounted for in terms of factors obtained from factor analysis of the original reaction time data. These factors lead to an alternative interpretation of the results which is contrasted with Vernon's interpretation. Part II of this study illustrates the use of confirmatory factor analysis with this kind of data. An attempt to test the assumptions of Vernon's difference score model with confirmatory factor analysis did not succeed because the implied model was too constrained for the statistical program we were using; consequently, the program could not find a starting solution. In order to demonstrate how confirmatory factor analysis can be used to test models of speed of cognitive processing, Part II partially replicates a study by Lansman, Donaldson, Hunt, & Yantis (1982). This research analyzed a simple cognitive reaction time task that was examined in detail by Vernon. Donaldson (1983) used the Lansman et al. data to compare difference scores and part correlational techniques with a general approach based on analysis of covariance structures to demonstrate how the components of cognitive processes can be explicated using confirmatory factor analysis.

Correlation between the RPRS total and WAIS FSIQ showed that approximately 43% of the variance in the RPRS total can be accounted for by the variance in the FSIQ. Verbal IQ is not significantly higher correlated with the RPRS total than the Performance IQ (p < .10). Factor analysis of the 6 RPRS subscores resulted in 2 factors. Subsequent factor analysis of the 6 RPRS subscores plus FSIQ and the factor analysis of the 6 RPRS subscores plus PIQ and VIQ showed the first factor to be an intelligence factor accounting for 85% of the common variance. The RPRS variables FL, FM, M and Sh loaded on this factor. The second factor was a nonintelligence factor accounting for 15% of the common variance. Small m is clearly the main determinant of this factor followed by Sh. In addition, the results of 2 exploratory factor analyses are discussed. The first exploratory factor analysis involved 23 variables, namely the 6 RPRS subscores, RPRS total, the 11 WAIS subscales, FSIQ, VIQ, PIQ, VIS and OABD. The second exploratory analysis involved 17 variables, namely the 6 RPRS subscores and the 11 WAIS subscales.

The present study was designed to test the causal locus hypothesis, and to develop and explore the selfevaluational hypothesis. The causal locus hypothesis is based on attribution, which is a person's perception of cause. The hypothesis holds that persons making internal attributions (self-caused) for failure end external attributions (not self-caused) for success experience more negative postoutcome mood than persons making external attributions for failure and internal attributions for success. The hypothesis was derived from major theories or attribution, but was not experimentally tested until recently (Wollert et al., 1981).

Four types of schedule interactions have been defined: positive contrast, negative contrast, positive induction, and negative induction. Most work has centered on the necessary conditions for positive contrast. One position states that a reduction in reinforcement frequency is necessary; the other view states that a reduction in response rate is necessary. Neither view can account for the occurrence of induction. The present experiment tests the hypothesis that stimulus control effects the occurrence of either contrast or induction. Three pigeons were trained to respond for primary reinforcement (strong stimulus control condition), and three pigeons were trained to respond for conditioned reinforcement (weak stimulus control condition). A response rate decrease was caused by changing the schedule of reinforcement from MULT EXT, VI 1-min, EXT, VI 1-min to MULT VI 1-min, VI 1-min, VI 1-min, VI 1-min for primary reinforcement birds, and to MULT (Chain VI 1-min, VI 1-min), (CHAIN VI 1-min, VI 1-min for conditioned reinforcement birds. Negative contract was observed for all birds receiving primary reinforcement, but positive induction occurred for two of three birds receiving conditioned reinforcement. In the next phase a response rate decrease was caused by changing the schedule to MULT VI 1-min, VI 1-min, DRO 20-sec, VI 1-min for primary reinforcement birds , and to MULT (CHAIN VI 1-min), VI 1-min, CHAIN DRO 20-sec , VI 1-min) for conditioned reinforcement birds. Two of the primary reinforcement birds showed positive contrast, while the third showed negative induction. Two of the conditioned reinforcement birds showed negative induction, while the third showed no effect. Gradients of stimulus control showed no difference between the groups due to the prolonged training before testing for stimulus control. It was concluded that differential amounts of stimulus control can account for the differences in the schedule interactions in this experiment and those observed in previous research.

A human performance experiment was conducted to investigate pixel parameter requirements for three types of flat-panel display images: an alphanumeric character, an oscilloscope waveform, and a real-world image. Subjects performed similarity judgments between an extremely high-quality image and an image composed of different levels of anti-aliasing and pixel width-plus-pixel separation (pitch). It was found that the effect of pitch had greater influence on perceived image quality for the alphanumeric character and oscilloscope waveform than for the real-world image. The results of this research provide empirical evidence showirg that the pixel pitch requirements for flat-panel systems that are used to display binary, high-contrast images (such as text and waveforms) will be more stringent than for low-contrast pictorial images. The three levels of grey-scale anti-aliasing investigated were found to improve image quality for only the binary, high-contrast images.

The purpose of the present study was to determine what, if any, relationship existed between the correspondence of perceptions between superior-subordinate work dyads and the superior's rating of the subordinate's work performance.