Adaptation of central pitch-specific mechanisms

Three previous psychophysical studies have demonstrated that interaural time difference (ITD) coding mechanisms can undergo frequency-specific, selective adaptation. We sought to determine whether this phenomenon extends to the pitch domain, by employing the same psycho-physical paradigm as one used previously, but with harmonic tone complexes lacking energy at the fundamental frequency. Ten normal listeners participated in experiment 1. Psychometric functions for ITDs were obtained for harmonic tone complexes with fundamental frequencies of 110 Hz and 185 Hz, before and after selective adaptation with complexes of the same fundamental frequencies lateralised to opposite sides. In experiment 1, each subject was tested twice. On separate days, subjects were tested with 110 Hz and 185 Hz stimuli that were either partially resolvable complexes or unresolvable ones. Both partially resolved and unresolved stimuli supported adaptation, and at both fundamental frequencies. In experiment 2, which employed nine listeners, the adaptor tone complexes were presented in conjunction with a diotic noise background designed to mask difference tones generated by the adaptor stimuli. The use of the masker had little effect on the mean strength of the adaptation effected by the unresolved adaptor stimuli, and only slightly weakened the adaptation effect found with the partially resolved adaptor stimuli. Taken together, these data constitute the first demonstration of selective adaptation exerted on a central mechanism in the pitch domain.     

The shaping of personality: genes, environments, and chance encounters

I started my career as a clinical psychologist with an interest in personality assessment. But a loss of faith in psychoanalytic theory, projective tests, and clinical case studies in general led to a shift in my interests to personality research. Subsequent jobs at research institutes and universities allowed me to indulge in science. I developed the trait-state concept and its application in tests for affect measurement. For 10 years I did experimental research in the field of sensory deprivation. The sensation seeking idea and tests evolved from this work but soon expanded to many other areas. Research in the biological basis of sensation seeking started with genetic and psychophysiological research, but research conducted in other laboratories also pointed to a psychopharmacological basis for the trait. Over the last several decades, I have formulated a psychobiological model for personality. I have used factor analysis and the biosocial model to develop an "alternative-five" factorial trait structure for personality.     

The Relationship Between Perceptions of Neighborhood Characteristics and Substance Use Among Urban African American Adolescents

Although the neighborhood microsystem is recognized as an important domain for adolescent development, relative to the family and peer contexts, neighborhood factors have been understudied in relation to adolescent substance abuse. In addition, recent research suggests that risk factors for adolescent substance use may differ for African Americans when compared to Caucasian youth. This study investigated the association between perceived neighborhood disorganization and later substance use, as well as possible mediators of that association, among a community sample of urban African American adolescents. Perceptions of neighborhood disorganization (i.e., violence/safety and drug activity) in grade 7 were associated with increased tobacco, alcohol, and marijuana use in grade 9. For females, this association was mediated by attitudes about drug use and perceptions of drug harmfulness. Findings highlight the importance of neighborhood contextual variables for African American substance use. Implications and directions for future research are presented.     

Self-awareness, self-evaluation, and creativity

The present research examined when self-evaluation influences creativity. Based on objective self-awareness theory, the authors predicted that feeling able to improve would buffer against the detrimental effects of self-evaluation on creativity. Two experiments manipulated self-evaluation (varying self-awareness, Study 1; providing objective performance standards, Study 2) and perceived ability to improve potential failure on the creativity task. Self-evaluation reduced creativity (generating remote associates, finding unusual uses for a knife) in both experiments, but only when people did not expect to improve. When people felt able to improve, self-evaluation did not affect creativity. Connections between self-motives, creativity, and defensiveness are discussed.     

Illusory Control and Motives for Control: The Role of Connection and Intentionality

An experiment was done to examine the control heuristic perspective on illusory control and the effects of motives on control judgments, using a computer task similar to the light onset task used in previous research. Desire for the outcome and reinforcement were manipulated. As predicted from a control heuristic perspective, the effect of level of reinforcement on judgments of personal control was mediated by the measure of perceived connection: the perception of the number of positive confirming cases. Motives increased illusions of control, but only in the high reinforcement condition. A mediational analysis that examined how motives affect control judgments found that when the motive to get the outcomes was high, participants had higher estimates of having acted intentionally and these estimates partially mediated the relationship between the motivation manipulation and judgments of control. It appears that perceptions of connection mediate the relationship between reinforcement and illusory control, while judgments of intentionality partially mediate the effect of motives for control and illusory control.     

Use of visual, acoustic, and olfactory information during embedded invertebrate foraging in brown capuchins (Cebus apella)

Experiments were conducted to investigate which sensory cues are used by brown capuchins (Cebus apella) in embedded invertebrate foraging. The importance of visual, olfactory, and acoustic cues in such foraging was determined by presenting subjects with a stimulus log modified to block out given sensory cues. Experiment 1 was designed to investigate whether subjects could locate an invertebrate embedded in wood when only visual, acoustic, or olfactory information was available. Experiments 2 and 3 were designed to investigate extractive foraging behavior when two sensory cues were provided. It was hypothesized that the combination of visual and acoustic information would be necessary for subjects to successfully locate embedded invertebrates. Results indicated that subjects' performance was most successful when both visual and acoustic information was available.     

Patterns of neural response to emotive stimuli distinguish the different symptom dimensions of obsessive-compulsive disorder

Despite its heterogeneous symptomatology, obsessive-compulsive disorder (OCD) is currently conceptualized as a unitary diagnostic entity. Recent factor-analytic studies have identified several OCD symptom dimensions that are associated with different demographic variables, comorbidity, patterns of genetic transmission, and treatment response. Functional abnormalities in neural systems important for emotion perception, including the orbitofrontal cortex, lateral prefrontal cortex, anterior cingulate gyrus, and limbic regions, have been reported in OCD. In this review, we discuss the extent to which neurobiological markers may distinguish these different symptom dimensions and whether specific symptom dimensions, such as contamination/washing, are associated with abnormalities in emotion and, in particular, disgust, perception in OCD. Also discussed are findings that indicate that anxiety can be induced in healthy volunteers in response to OCD symptom-related material, and that associated increases in activity within neural systems important for emotion perception occur to washing- and hoarding-related material in particular in these subjects. Further examination of neural responses during provocation of different symptom dimensions in OCD patients will help determine the extent to which specific abnormalities in neural systems underlying emotion perception are associated with different symptom dimensions and predict treatment response in OCD.     

The role of structural prediction in rapid syntactic analysis

A number of recent electrophysiological studies of sentence processing have shown that a subclass of syntactic violations elicits very rapid ERP responses, occurring within around 200 ms of the onset of the violation. Such findings raise the question of how it is possible to diagnose violations so quickly. This paper suggests that very rapid diagnosis of errors is possible specifically in situations where the diagnosis problem is tightly constrained by specific expectations generated before the critical word is presented. In an event-related potentials (ERP) study of visual sentence reading participants encountered violations of a word order constraint (...Max's of...) that has elicited early ERP responses in previous studies. Across conditions the illicit sequence was held constant, while sentence context was used to manipulate the expectation for a noun following the possessor Max's, by manipulating the possibility of ellipsis of the head noun. Results showed that the anterior negativity elicited by the word category violation was attenuated when the availability of ellipsis reduced the expectation for a noun in the position of the offending preposition of, with divergence between conditions starting around 200 ms after the onset of the violation. This suggests a role for structural expectations in accounting for very fast syntactic diagnosis processes.     

Family secrecy: a comparative study of juvenile sex offenders and youth with conduct disorders

The reported research was designed to compare adjudicated male juvenile sexual offenders and youth with conduct disorders on five aspects of family secrecy and deception. Twenty-nine male juvenile sex offenders and 32 comparison youth from three child welfare agencies in New York State participated in the study. Research assistants, blind to the hypotheses of the study and status of the youth, coded agency records for five variables identified a priori as a basis of comparison. Analyses revealed that the two groups were different on three of the five and on the total number of items scored. Families of juvenile sex offenders told more lies, had more family myths, and were more likely to be involved in taboo behavior. Logistic regression revealed that this factor of family deception significantly increased the odds of sexual offending over and above other measures of family pathology. These data support the hypotheses of the study and have implications for both clinical practice and future research in this area.