Unusual visual symptoms and Ganser-like state due to cerebral injury: a case study using (18)F-deoxyglucose positron emission tomography

Bizarre visual symptoms and absurd verbal responses to questions, in a 32-year-old man recovering from a severe asthma episode, suggested a possible conversion disorder with Ganser-like symptoms. Positron Emission Tomography (PET)revealed bilateral lesions involving occipital association cortex and posterior temporal and parietal lobes, most likely infarcts from hypoxia. PET permitted correlation of the patient's specific cortical lesions with his unusual perceptual, cognitive, and speech symptoms, including Ganser-like state, to a degree not previously possible in such cases.     

Auditory event perception: The source—perception loop for posture in human gait

There is a small but growing literature on the perception of natural acoustic events, but few attempts have been made to investigate complex sounds not systematically controlled within a laboratory setting. The present study investigates listeners’ ability to make judgments about the posture (upright—stooped) of the walker who generated acoustic stimuli contrasted on each trial. We use a comprehensive three-stage approach to event perception, in which we develop a solid understanding of the source event and its sound properties, as well as the relationships between these two event stages. Developing this understanding helps both to identify the limitations of common statistical procedures and to develop effective new procedures for investigating not only the two information stages above, but also the decision strategies employed by listeners in making source judgments from sound. The result is a comprehensive, ultimately logical, but not necessarily expected picture of both the source—sound—perception loop and the utility of alternative research tools.     

Testing hypotheses about the self: Assessments of job suitability1

This investigation examined the strategies employed by individuals when testing hypotheses about the self. Participants known to possess masculine, feminine, or androgynous sex role identities tested hypotheses about their suitability for one of two jobs: either a job characterized in terms of the attributes and aptitudes typically associated with a “masculine” personality, or one characterized in terms of those typically associated with a “feminine” personality. When testing these hypotheses about themselves, participants preferentially reported those aspects of themselves that would suggest their suitedness rather than their unsuitedness for the job under consideration regardless of their sex role identity. Moreover, subsequent judgments of job suitability were positively related to the amount of suitedness evidence reported, but unrelated to the amount of unsuitedness evidence reported. Some consequences of these strategies for testing hypotheses about the self are discussed.     

Working and long-term memory deficits in schizophrenia: is there a common prefrontal mechanism?

This study tested the hypothesis that dorsolateral prefrontal cortex deficits contribute to both working memory and long-term memory disturbances in schizophrenia. It also examined whether such deficits were more severe for verbal than nonverbal stimuli. Functional magnetic resonance imaging was used to assess cortical activation during performance of verbal and nonverbal versions of a working memory task and both encoding and recognition tasks in 38 individuals with schizophrenia and 48 healthy controls. Performance of both working memory and long-term memory tasks revealed disturbed dorsolateral prefrontal cortex activation in schizophrenia, although medial temporal deficits were also present. Some evidence was found for more severe cognitive and functional deficits with verbal than nonverbal stimuli, although these results were mixed.     

Targets' Awareness of Expectations and Behavioral Confirmation in Ongoing Interactions

Participants engaged in a getting-acquainted interaction over an intercom after one participant (the perceiver) was provided with a positive (extraverted) or relatively negative (introverted) expectation about the other participant (the target). After completing evaluations of each other and the interaction, participants interacted for a second time. Prior to this second interaction, however, targets were made aware of the perceivers' initial expectation, told that it had been confirmed by their own behavior, and given a randomly assigned attribution (either dispositional or situational) about the perceived cause of their confirmatory behavior. Results demonstrated that targets made aware of dispositionally attributed and relatively negative expectations were more likely to increase in expectation-disconfirming behavior, compared to targets made aware of situationally attributed and relatively negative expectations, who were themselves more likely to continue to confirm the expectations. Implications for the study of behavioral confirmation of expectations and other interpersonal processes are discussed.     

Differential age effects for case and hue mixing in visual word recognition

The authors compare older adults' lexical-decision data with younger adults' data reported in P. Allen, A. F. Smith, et al. (2002). On the basis of their work, it was proposed that consistent-case wordswould be processed by the faster holistic (magnodominated) stream, but that mixed-case words would be processed by the slower analytic (interblob-dominated or blob-dominated) steams. Hue mixing was predicted to have no effect on consistent-case performance, but mixed-hue/mixed-case words were predicted to be recognized faster than monochrome/mixed-case words. Younger adults showed the predicted results, but older adults did not. These results suggest that holistic central processes are maintained, but that older adults exhibited an analytic decrement     

Inhibition of return and visual search: how many separate loci are inhibited?

Using a novel sequential visual search paradigm Danziger, Kingstone, and Snyder (1998) demonstrated that inhibition of return (IOR) can reside at three spatial locations. In the present study, we extended the work of Danziger et al. by investigating whether there is a limit to the number of locations that can be inhibited in a sequential visual search task. Our study revealed that IOR can be measured at a minimum of five locations. The magnitude of the IOR effect was largest at the most recently searched location and declined from there in an approximately linear fashion. Two models that can account for our data are presented.