Faculty Bibliography

Learning and memory depend on signaling molecules that affect synaptic efficacy. The cytoskeleton has been implicated in regulating synaptic transmission but its role in learning and memory is poorly understood. Fear learning depends on plasticity in the lateral nucleus of the amygdala. We therefore examined whether the cytoskeletal-regulatory protein, myosin light chain kinase, might contribute to fear learning in the rat lateral amygdala. Microinjection of ML-7, a specific inhibitor of myosin light chain kinase, into the lateral nucleus of the amygdala before fear conditioning, but not immediately afterward, enhanced both short-term memory and long-term memory, suggesting that myosin light chain kinase is involved specifically in memory acquisition rather than in posttraining consolidation of memory. Myosin light chain kinase inhibitor had no effect on memory retrieval. Furthermore, ML-7 had no effect on behavior when the training stimuli were presented in a non-associative manner. Anatomical studies showed that myosin light chain kinase is present in cells throughout lateral nucleus of the amygdala and is localized to dendritic shafts and spines that are postsynaptic to the projections from the auditory thalamus to lateral nucleus of the amygdala, a pathway specifically implicated in fear learning. Inhibition of myosin light chain kinase enhanced long-term potentiation, a physiological model of learning, in the auditory thalamic pathway to the lateral nucleus of the amygdala. When ML-7 was applied without associative tetanic stimulation it had no effect on synaptic responses in lateral nucleus of the amygdala. Thus, myosin light chain kinase activity in lateral nucleus of the amygdala appears to normally suppress synaptic plasticity in the circuits underlying fear learning, suggesting that myosin light chain kinase may help prevent the acquisition of irrelevant fears. Impairment of this mechanism could contribute to pathological fear learning

There is a great need to better understand the impact of traumatic events very early in life on the course of children's future development. This report focuses on the intriguing case of a girl who witnessed the murder of her mother by her father at the age of 19 months and seemed to have no recollection of this incident until the age of 11, when she began to exhibit severe symptoms of posttraumatic stress disorder (PTSD) in response to a traumatic reminder. The case presentation serves as the basis for a discussion regarding pertinent issues involved in early childhood trauma. This case and accompanying discussion were originally presented at the 19th Annual Meeting of the International Society for Traumatic Stress Studies and were transcribed and revised for use in this article. Specific topics include early childhood memory and trauma, learning and the appraisal of danger, and PTSD and traumatic grief in early childhood. Clinical and public health implications are also discussed. This case illustrates the dramatic impact that 'preverbal' traumatic memories can have on children's later functioning and speaks to the importance of assisting very young children in the immediate aftermath of traumatic events

The purpose of this study was to evaluate the factor structure of the Liebowitz Social Anxiety Scale for Children and Adolescents (LSAS-CA). The LSAS-CA was administered to 225 children and adolescents as a component of various clinical studies. In addition, other measures of psychopathology and impairment were administered to a subgroup of the sample. Confirmatory factor analyses of the social interaction and performance subscales for the anxiety and avoidance ratings yielded poor fit indices. Exploratory factor analysis supported a two-factor solution with a higher order factor for the LSAS-CA anxiety and avoidance ratings. Based on item content, factors were named Social and School Performance. The internal consistency of the factors was high and the convergent and divergent validity was supported vis-a-vis correlations with measures of depression and social anxiety, and clinician ratings of impairment and functioning. Findings suggest that the anxiety and avoidance ratings are best explained by a two-factor solution that measures social anxiety and avoidance in social and school performance interactions. This factor structure appears to be a reliable and valid framework for assessing childhood social phobia.

This study uses qualitative data from individual interviews with low-income, African American women (n = 92) between 19 and 35 years of age who participated in 12 two-hour sessions of a family-focused HIV prevention intervention. The study explores influences on three domains. At the individual domain, development of personal attributes and the perceptions that program staff was fair toward racial minorities appear to influence participation. At the program domain, staff friendliness and monetary incentive also influenced participation. At the social domain, influence of friends and emotional support influenced participation. Training staff to confront racism and to develop a culturally competent and friendly environment has the potential to increase attendance among participants at high risk for HIV exposure.