Faculty Bibliography

This study examined whether 16-month-old walking infants take the material composition of a handrail into account when assessing its effectiveness as a tool to augment balance. Infants were encouraged to cross from one platform to another via bridges of various widths (10, 20, 40 cm) with either a "wobbly" (foam or latex) or a wooden handrail available for assistance. Infants attempted to walk over wider bridges more often than narrow ones, and attempts were more frequent when the sturdy wooden handrail was available. Infants tailored their exploratory behaviors, bridge-crossing strategies, and handrail-use strategies to the material properties of the rail.

Unraveling the functional role of neuromodulatory systems has been a major challenge for cognitive neuroscience, giving rise to theories ranging from a simple role in vigilance to complex models concerning decision making, prediction errors or unexpected uncertainty. A new, simplified and overarching theory of noradrenaline function is inspired by an invertebrate model: neuromodulators in crustacea abruptly interrupt activity in neural networks and reorganize the elements into new functional networks determining the behavioral output. Analogously in mammals, phasic activation of noradrenergic neurons of the locus coeruleus in time with cognitive shifts could provoke or facilitate dynamic reorganization of target neural networks, permitting rapid behavioral adaptation to changing environmental imperatives. Detailed analysis and discussion of extensive electrophysiological data from the locus coeruleus of rats and monkeys in controlled behavioral situations is provided here to support this view. This simplified 'new look' at locus coeruleus noradrenaline function redirects the challenge of understanding neuromodulatory systems towards their target networks, particularly to the dynamics of their interactions and how they organize adaptive behavior

Approximately 50% of families of children with ADHD fail to pursue, or adhere to, recommended treatments. The present study examines parent ratings of the acceptability of pharmacological and behavioral treatments for ADHD and the relationships between these ratings and subsequent pursuit of treatment. Fifty-five families whose children received an evaluation for ADHD completed questionnaires and were contacted 3 to 4 months later to assess their pursuit of treatment. Consistent with previous research, parents rated behavior therapy as more acceptable than medication. Parent ratings of medication acceptability significantly predict pursuit of pharmacological treatment, whereas ratings of the acceptability of behavior therapy do not predict pursuit of this treatment. Preliminary analyses found that Caucasian parents' ratings of medication are significantly higher than those of non-Caucasian parents. Furthermore, Caucasian families were more likely to pursue a recommendation for pharmacological treatment than non-Caucasian families. The clinical and research implications of these results are considered

Fear conditioning represents the process by which a neutral stimulus comes to evoke fear following its repeated pairing with an aversive stimulus. Although fear conditioning has long been considered a central pathogenic mechanism in anxiety disorders, studies employing lab-based conditioning paradigms provide inconsistent support for this idea. A quantitative review of 20 such studies, representing fear-learning scores for 453 anxiety patients and 455 healthy controls, was conducted to verify the aggregated result of this literature and to assess the moderating influences of study characteristics. Results point to modest increases in both acquisition of fear learning and conditioned responding during extinction among anxiety patients. Importantly, these patient-control differences are not apparent when looking at discrimination studies alone and primarily emerge from studies employing simple, single-cue paradigms where only danger cues are presented and no inhibition of fear to safety cues is required.

BACKGROUND: Delusions are a central feature of schizophrenia, yet our understanding of their neurobiology is limited. Attempt to link dimensions of psychopathology to putative neurobiological mechanisms depends on careful delineation of symptoms. Previous factor analytic studies of delusions in schizophrenia were limited by several methodological problems, including the use of patients medicated with antipsychotics, inclusion of nondelusion symptoms in the analyses, and/or inclusion of patients with psychotic disorders other than schizophrenia. These problems may have possibly biased the resulting factor structure and contributed to the inconclusive findings regarding the neurobiology of positive symptoms. Our goal is to examine the factor structure of delusions in antipsychotic-free individuals with diagnoses of schizophrenia/schizoaffective disorder. SAMPLING AND METHODS: We assessed 83 antipsychotic-free individuals with DSM-IV diagnoses of schizophrenia/schizoaffective disorder. A principal component analysis was conducted on the delusions symptoms of the SAPS. RESULTS: The principal component analysis resulted in three distinct and interpretable factors explaining 58.3% of the variance. The Delusions of Influence factor was comprised by delusions of being controlled, thought withdrawal, thought broadcasting, thought insertion, and mind reading. The Self-Significance Delusions factor was comprised by delusions of grandeur, reference, religious, and delusions of guilt/sin. The Delusions of Persecution factor was comprised solely by persecutory delusions. The three factors displayed distinct associations with hallucinations, bizarre behavior, attention, positive formal thought disorder, and avolition/apathy. CONCLUSIONS: The results indicate that delusions are best described by three distinct subtypes. The authors propose a novel model linking the three delusion subtypes, attributions to self/other, and putative neurobiological mechanisms. Implications for future research are discussed, as well as links to cognitive-behavioral conceptualizations of delusions

BACKGROUND: This and the companion paper present two sequential family studies of obsessive-compulsive disorder (OCD) conducted by the same research group, but with different sampling and best-estimate procedures. In addition to providing further data on familial transmission of OCD, we used comparison of disparate findings (moderate, specific familial aggregation in this first study versus a stronger effect for other anxiety disorders than for OCD alone in the second) to examine possible effects of proband characteristics and informant data on outcome. METHOD: In this initial study we interviewed 179 first-degree relatives of 72 OCD probands and 112 relatives of 32 never mentally ill (NMI) controls. Informant data were obtained on an additional 126 relatives (total 'combined' samples of 263 and 154 respectively). Analyses used best-estimate diagnoses made by consensus of two 'blinded' senior clinicians who reviewed all diagnostic materials including proband informant data about relatives. RESULTS: Significantly higher risk for OCD but not other anxiety disorders was found in relatives of OCD probands compared to relatives of controls in both the directly interviewed and combined samples. There was no relationship between proband age at onset of OCD and strength of familial aggregation. CONCLUSIONS: These data indicate moderate familial aggregation of OCD, but do not support increased transmission by early onset probands, or a familial relationship between OCD and other anxiety disorders with the possible exception of generalized anxiety disorder

BACKGROUND: Overall findings of our first direct interview family study of obsessive-compulsive disorder (OCD) indicated that OCD is familial. In this replication study, we carefully examined the role of informant data in ascertaining OCD in relatives. METHOD: We interviewed 112 relatives of 57 OCD patients and 115 relatives of 41 not ill controls predominantly by telephone. Additional analyses included a combined sample of relatives about whom any diagnostic information was available (228 OCD and 239 controls). To examine the contribution of proband information about relatives, we considered two sets of best-estimate diagnoses. First, we ascertained best-estimate diagnoses for relatives using information from direct interviews and from all informants except the proband. Then, we re-diagnosed relatives based on all available information, including reports from the proband about their relatives. RESULTS: When relative diagnoses were derived without the benefit of proband informant reports, no evidence of familial OCD transmission was found. When diagnoses were made including information from the proband about the relative, evidence of familial OCD was found, but only when the diagnostic threshold was lowered to include cases with probable OCD or OCD symptoms. Other diagnoses (generalized anxiety disorder, social phobia, drug use disorder) were also higher among OCD relatives. CONCLUSIONS: This second study provides less robust support for familial transmission of OCD. Evidence for familial transmission of OCD was found only when diagnoses were made using information from the affected proband about their relatives. Taken in context of past findings, our own inconsistent results suggest that OCD may be heterogeneous with regard to familial transmission. Also, more careful attention should be paid to the contribution of informant reports, especially from relatives affected by the same disorder

Premorbid intellectual function estimation is a crucial part of patient evaluation following a traumatic brain injury (TBI), especially in individuals with ADHD who are at higher risk for TBI compared to their non-ADHD peers. This study investigates the value of using regression-based estimates of intelligence for concurrently predicting measured intelligence in a sample of older adolescents with and without a childhood history of ADHD. Correlations between measured and estimated intelligence are highly significant in the full sample and in the individual groups. Adding reading performance to the regression equation increases the accounted-for variance in both groups. Results indicate that regression equations based on demographic characteristics constitute a valid method for estimating premorbid functioning in adolescents with ADHD and that they can play an essential role in the assessment of individuals with ADHD who sustain TBI, especially when measures of word reading are used to augment demographic estimates.