Events held in Sunburst Room unless otherwise noted.

Friday, October 21

Saturday, October 22

Abstracts

David Creswell

Title: Mindfulness Meditation Training: An Experimental Model for Probing Stress Regulation Mechanisms
Abstract: There has been a dramatic increase in the use of meditation practices in the West in recent years, in part due to their purported stress reduction benefits. This health neuroscience talk will describe one practice—mindfulness meditation—and how it fosters an open and accepting attentional stance toward one’s experience. Then experimental work will be described showing how mindfulness and mindfulness meditation training impact functional stress regulation circuitry in the brain in ways that reduce stress and impact health outcomes in at-risk stressed patient populations.

Kirk Erickson

Title: Physical activity training on brain and cognition in late life
Abstract: Cognitive impairment in late life might not be as inevitable as previously thought. In fact, the field of health neuroscience has discovered that our lifestyles and habits can have a significant impact on cognitive and brain health throughout the lifespan. For example, recent cross-sectional, longitudinal, and intervention research has found that only modest amounts of aerobic exercise is sufficient to protect and enhance cognitive and brain function in late life, and that these effects may also extend to populations with manifest cognitive impairment. This talk will review recent results demonstrating that aerobic exercise has the capacity to increase the size of the hippocampus and prefrontal cortex and that the effect of exercise on the brain appears to extend beyond a mere vascularization hypothesis. The relatively widespread effect of exercise on brain and cognition suggests that there are multiple mediating pathways linking exercise to cognitive function. Along these lines, results will be highlighted that support the idea that exercise-related changes in functional connectivity and volume partially mediate the improvements in executive and memory function. In contrast, obesity is associated with impaired white matter and functional connectivity throughout the lifespan. Understanding and defining the mechanisms by which exercise and obesity influence brain health is of utmost importance for appreciating brain-body associations throughout the lifespan.

Peter Gianaros

Title: The functional neuroanatomy of cardiovascular stress reactivity
Abstract: An individual's tendency to show exaggerated cardiovascular reactions to acute psychological stressors confers risk for premature cardiovasculardisease. However, the brain circuits that regulate stressor-evoked cardiovascular reactions and link them to disease risk remain poorly defined in humans. This presentation will highlight a line of health neuroscience research indicating that individual differences in cardiovascular reactivity relate to the functionality of a network of paralimbic brain areas that are involved in processing stressors and regulating the cardiovascular system. Preliminary evidence will also be reviewed indicating that individual differences in the functional activity of components of this network are associated with preclinical atherosclerosis. Contextually, this research will be offered as one example of how imaging methods can help to define the “brain-body” pathways that link stressful experiences to physical health.

Lori Holt

Title: Using speech to listen in on auditory processing
Abstract: The speech signal presents many cognitive and perceptual challenges to listeners and, as an ecologically-significant complex sound, it presents the opportunity to investigate higher-order auditory processing. I will describe a series of studies from our laboratory that exploit the perceptual challenges presented by speech to investigate general characteristics of auditory perception and learning. These issues include the extreme context-dependence of speech, the influence of experience on perception of speech, and effects of feedback from higher-order representations on speech perception. Our results demonstrate that there are reciprocal advantages to studying speech from a general auditory perspective: studying this complex acoustic signal provides insight into auditory processing and, likewise, constrains theories of speech perception.

George Loewenstein

Title: Implication of an Evolutionary Account of Emotion
Abstract: I will discuss a variety of research projects that examine the implications of an evolutionary account of emotion. According the evolutionary account, emotions are all-encompassing 'programs' that prepare us to react to recurring situations of evolutionary significance. When we are in different emotional states, the evolutionary account suggests, we are so profoundly transformed that we are, in effect, 'different people'. Such an account helps to make sense of research findings I will discuss which show (1) how profoundly emotions affect judgment and decision making, and (2) how little insight we have into our own (and others') behavior in emotional states different from that which we are currently experiencing.

Carl Olson

Title: Where in the Brain is Value Represented?
Abstract: Neurons in many areas of the cerebral cortex respond to cues predicting an upcoming reward. These neurons might represent value in an economically meaningful sense: the monkey might decide on the basis of their firing how hard to work or what to do. Alternatively, they could be involved in secondary processes set in motion by the reward-predicting cue, including motivated engagement (monkeys work harder for a more valued reward) and attention (a cue associated with reward captures attention automatically). I will describe experiments designed to tease apart these forms of reward-related activity. The results suggest that neuronal activity represents value in limbic cortex, motivation in premotor cortex and the automatic capture of attention by salient cues in parietal cortex.

Richard Randall

Title: Neuroimaging studies often rely on averages of multiple trials to represent their findings. Such averaging is necessary in order to control for unwanted artefacts and noise. In studies that explore the differences in neurological response to musical sequences, analysis of averaged data sets have been used to support theories of expectation, syntax, and consonance and dissonance. Results are based on the comparison of two or more experimental conditions and have been used to isolate which kinds of musical events evoke different kinds of neural responses. Averaging across an entire set of trials, however, has the effect of transforming a diachronic experience (listening to a stimulus multiple times) into an artificial single listening experience. Music scholars frequently discuss the impact of multiple hearing on the perception and understanding of music. In general, however, neuroimaging studies musical expectation do not account for such "rehearings." This study attempts to address the issue of rehearings in neuroimaging studies by employing a novel method of data analysis that capitalizes on diachronic listening and describes how the neural response to a stimulus changes over time.

Floh Thiels

Title: Control by cues over pursuit of reward: Stories from deep in the brain
Abstract: Cues that have come to predict reward as a consequence of Pavlovian conditioning can potentiate behaviors aimed at obtaining the reward. The potentiation of reward-seeking behaviors by conditioned cues generally is adaptive; it enables animals to take better advantage of the resources around them and thereby enhances survival and biological fitness. However, it can also be detrimental by contributing to the uncontrollable pursuit of reward, as occurs in the case of drug addiction, gambling, or obesity. Conditioned cue-potentiation of reward seeking depends on the nucleus accumbens, a midbrain structure that is highly interconnected with limbic and motor regions and is subject to dopaminergic modulation. The molecular mechanisms within the accumbens that underlie cue-potentiation of reward seeking are not well understood. I will present findings from my lab that assign a key role to the extracellular signal regulated kinase cascade to this motivational effect of conditioned cues. I also will discuss findings from on-going work on the mechanisms through which this protein kinase pathway is activated by conditioned cues, the consequences of activation of this signaling pathway on accumbal cell function, and the effect of repeated exposure to a drug of abuse on cue-evoked activation of this signaling pathway and on reward seeking. The work elucidates a molecular substrate of conditioned motivational control and has implications for our understanding of the neural processes that contribute to costly maladaptive behavioral conditions, such as addiction and obesity.

Thanos Tzounopoulos

Title: Zinc as a Neurotransmitter that Controls Synaptic Strength
Abstract: Glutamatergic neurons sequester Zn2+ within their synaptic vesicles, but the physiological significance of synaptic Zn2+ release remains poorly understood. We show that Zn2+ acts as a neurotransmitter, triggering endocannabinoid synthesis following activation of a postsynaptic Zn2+-sensing metabotropic receptor (mZnR). The postsynaptic production of endocannabinoids, in turn, inhibits presynaptic probability of neurotransmitter release (Pr). Mice lacking vesicular Zn2+ or the mZnR lack synaptic Zn2+ modulation of Pr. Moreover, mass spectrometry analysis confirms that Zn2+- mediated increases in endocannabinoid levels are dependent on the presence of mZnRs. Zn2+-mediated modulation of Pr is a conserved signaling pathway sharing mechanistic features in auditory nuclei and in the hippocampus. Given the widespread distribution of vesicular Zn2+ and endocannabinoids, we propose that this fundamental interaction between Zn2+ and endocannabinoid synthesis provides a general mechanism for dynamic control of Pr throughout the brain.

Shimon Ullman

Title: Objects and parts: bottom-up, top-down and context
Abstract: Object categorization and recognition are complex visual tasks that involve large interacting brain systems. I will describe an approach which learns to recognize natural categories, individual objects, and their parts at multiple levels. Starting from image examples, the model constructs objects representations using a hierarchy of shared sub-structures called fragments, selected by maximizing the information delivered for recognition. Recognition of objects and their parts is obtained by a feed-forward sweep from low to high levels of the hierarchy, followed by a sweep from the high to low levels. Residual local ambiguities are resolved by using their surrounding context. I will describe results of applying the model to natural object classes, and discuss relationships between the model and parts of the primate visual system involved in object perception.