Faculty Bibliography

The neurobiology of memory has taken on a new look over the past decade. Re-discovery of cue-dependent amnesia, wide availability of functional imaging tools and increased dialog among clinicians, cognitive psychologists, behavioral neuroscientists, and neurobiologists have provided impetus for the search for new paradigms for the study of memory. Memory is increasingly viewed as an open-ended process, with retrieval being recognized as an intricate part of the encoding process. New memories are always made on the background of past experience, so that every consolidation is, in fact reconsolidation, serving to update and strengthen memories after retrieval. Spontaneous reactivation of memory circuits occurs during sleep and there is converging evidence from rodent and human studies that this is an important part of the extended off-line memory processing. The noradrenergic neuromodulatory system is engaged at retrieval, facilitating recall. The noradrenergic system is also activated during sleep after learning and noradrenergic neurons fire in concert with cortical oscillations that are associated with reactivation of memory circuits. We suggest that the noradrenergic system and perhaps other neuromodulatory systems, may be a key to linking off-line memory reactivation, retrieval, and memory reconsolidation processes at both synaptic and systems levels, in and out of sleep

Adults produce left-lateralized N170 responses to visual words relative to control stimuli, even within tasks that do not require active reading. This specialization begins in preschoolers as a right-lateralized N170 effect. We investigated whether this developmental shift reflects an early learning phenomenon, such as attaining visual familiarity with a script, by training adults in an artificial script and measuring N170 responses before and afterward. Training enhanced the N170 response, especially over the right hemisphere. This suggests N170 sensitivity to visual familiarity with a script emerges before reading becomes sufficiently automatic to drive left-lateralized effects in a shallow encoding task.

Objective: This study examines the impact of the Family Connections (FC) intervention on preventing behavioral problems among urban, predominantly African American children at risk of neglect. Method: Secondary data analyses using mixed model analyses of variance (ANOVA) with repeated measures were used to examine gender differences in child behavior outcomes among 111 participating families across three time points (intake, closing, and 6 months following intervention participation). Results: From intake to closing, boys appeared to experience a larger decrease in internalizing and externalizing behaviors than girls. At 6-month follow-up, boys' behaviors remained stable relative to results at closing; girls showed a slight decrease in behaviors over the same period. Findings also indicate a greater decrease in problem behaviors for participants in the 9-month versus 3-month version of FC. Conclusions: Positive effects of the FC intervention for African American children indicate the potential of this prevention intervention to avert negative behavior trajectories.

The Building Bridges Initiative (BBI) provides a framework for achieving positive outcomes for youth and families served in residential and community programs. Founded on core principles, an emerging evidence base, and acknowledged best practices, the BBI emphasizes collaboration and coordination between providers, families, youth, advocates, and policymakers to achieve its aims. Examples are presented of successful state, community, and provider practice changes, and available tools and resources to support all constituencies in achieving positive outcomes.

The ongoing Israeli-Palestinian conflict has taken its toll on both sides. Prominent among peace building initiatives is the Parents Circle-Families Forum, a cross-community peace building project of bereaved families. We examine the grieving process and emotional well-being of a sample of 21 Israeli Jews and Palestinians living in the West Bank, who have lost their loved ones in the context of ongoing war and armed conflict. We also investigate whether the positive attitudes and emotions toward the opposing groups can serve as protective factors associated with prolonged grief disorder (PGD). The most prominent finding of our study is that some attitudes (e.g., a positive attitude toward peace, being hopeful about the future, the ability to forgive the opposing group) can be considered protective factors associated with PGD. People-to-people peace building initiatives, such as the Parents Circle-Families Forum, reinforce these factors. Furthermore, they provide their members with social support and a strong sense of mutual commitment and responsibility, facilitating their grieving process, and emotional well-being.

Norepinephrine (NE) is thought to play a key role in fear and anxiety, but its role in amygdala-dependent Pavlovian fear conditioning, a major model for understanding the neural basis of fear, is poorly understood. The lateral nucleus of the amygdala (LA) is a critical brain region for fear learning and regulating the effects of stress on memory. To understand better the cellular mechanisms of NE and its adrenergic receptors in the LA, we used antibodies directed against dopamine beta-hydroxylase (DbetaH), the synthetic enzyme for NE, or against two different isoforms of the beta-adrenergic receptors (betaARs), one that predominately recognizes neurons (betaAR 248) and the other astrocytes (betaAR 404), to characterize the microenvironments of DbetaH and betaAR. By electron microscopy, most DbetaH terminals did not make synapses, but when they did, they formed both asymmetric and symmetric synapses. By light microscopy, betaARs were present in both neurons and astrocytes. Confocal microscopy revealed that both excitatory and inhibitory neurons express betaAR248. By electron microscopy, betaAR 248 was present in neuronal cell bodies, dendritic shafts and spines, and some axon terminals and astrocytes. When in dendrites and spines, betaAR 248 was frequently concentrated along plasma membranes and at post-synaptic densities of asymmetric (excitatory) synapses. betaAR 404 was expressed predominately in astrocytic cell bodies and processes. These astrocytic processes were frequently interposed between unlabeled terminals or ensheathed asymmetric synapses. Our findings provide a morphological basis for understanding ways in which NE may modulate transmission by acting via synaptic or non-synaptic mechanisms in the LA

Odors that we encounter everyday are usually very complex. While the olfactory system is capable of discriminating complex yet similar odors (e.g. mocha and latte) with practice, the underlying mechanisms are not clear. As more data have been reported in anesthetized animals, data from awake animals are few. This experiment was therefore designed to investigate two related questions in awake rats: 1) odor coding of complex mixture in the anterior piriform cortex (a PCX) and 2) fear conditioning effects on odor coding in the a PCX. To record activity from awake animals, Long-Evans hooded rats were chronically implanted with movable bundles of microwires aimed at the a PCX. Up to 7 units were recorded simultaneously, and the electrode bundle was moved over time to sample additional cells. Odor-shock conditioning was performed to induce odor-related aversive experience on the rats, with a complex 10-odorant mixture as the conditioned stimulus (CS). The CS odor, along with overlapping odor mixtures and limonene were presented to the animals before the conditioning trials and for several days post-training. The results (n = 206 units) showed a slight decrease in percentage of units that showed excitation after conditioning, and a significant increase in suppression. A significant decrease in average spontaneous activity was observed after conditioning. Finally, an analysis of single-unit responsiveness revealed a late suppressive response after conditioning to all three mixtures overlapping with the CS but not limonene. Interestingly, while responsiveness to control odors decreased after conditioning, responses to the CS became temporally focused, with a more narrow range of onset and offset latencies. Together, odor fear conditioning should enhance signal:noise and CS coding acuity in a PCX

Beta-adrenergic receptors (betaARs) have long been associated with fear disorders and with learning and memory. However, the contribution of these receptors to Pavlovian fear conditioning, a leading behavioral model for studying fear learning and memory, is still poorly understood. The aim of this study was to investigate the involvement of betaAR activation in the acquisition, consolidation and expression of fear conditioning. We focused on manipulations of betaARs in the lateral nucleus of the amygdala (LA) because of the well-established contribution of this area to fear conditioning. Specifically, we tested the effects of intra-LA microinfusions of the betaAR antagonist, propranolol, on learning and memory for auditory Pavlovian fear conditioning in rats. Pre-training propranolol infusions disrupted the initial acquisition, short-term memory (STM), and long-term memory (LTM) for fear conditioning, but infusions immediately after training had no effect. Further, infusion of propranolol prior to testing fear responses did not affect fear memory expression. These findings indicate that amygdala betaARs are important for the acquisition but not the consolidation of fear conditioning.