Faculty Bibliography

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.

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 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

The present study investigated the time course of attentional bias for angry and happy faces in 50 primary school children (9 to 12 years). That is, the study examined the degree to which an anxiety-related attentional bias was moderated by the duration of threat exposure. Using a visual-probe task, children were shown angry and happy faces paired with neutral ones over two exposure durations: 500 and 1250 ms. Results revealed that higher levels of anxiety were associated with an attentional bias towards angry faces across the 500 ms and 1250 ms exposure durations. There were no effects of children's anxiety or stimulus exposure duration on attentional bias for happy faces. Results are discussed in relation to threat-monitoring versus vigilance-avoidance patterns of attentional bias, and developmental considerations, including comparison with findings from studies of anxiety-related attentional biases in adults.