Project Summary/Abstract Improved understanding of the brain processes underlying normal and abnormal function is necessary for devising better ways to diagnose, alleviate, or cure neurological or psychiatric disorders. It is clear that even for simple behaviors, such processes depend on interactions among multiple brain regions. However, these interactions themselves are less well understood.
ABSTRACT Humans interact with their environment in countless ways and can switch seamlessly between activities. Even for seemingly simple tasks, a variety of sensory inputs are integrated to create a motor plan to complete a task. Take the example of picking up a glass. Visual, tactile, and proprioceptive inputs provide cues about the position and weight of the object as well as limb state. Additional sensory and contextual inputs can also influence the movement. For example, a person might pick up a glass differently if she is intending to take a drink, versus clear off a table.
Humans have a remarkable ability to flexibly interact with the environment. A compelling demonstration of this cognitive flexibility is our ability to perform complex, yet previously un-practiced tasks successfully on the first attempt.
Project Summary/Abstract Memory is critical for cognitive well-being, and sleep is critical for memory consolidation, yet the underlying mechanisms in the human brain are poorly understood. Research on memory and sleep so far has suffered from a substantial gap between non-invasive cognitive research in humans and detailed electrophysiological research in animals.
Cortical Signature and Modulation of Pain Abstract/Project Summary Pain perception contains two main dimensions: the sensory-discriminative and the affective-cognitive aspects. In this proposal, we will focus on the cortical signature and modulations of the sensory aspects of pain using mouse models. Pain can be largely divided into inflammatory or neuropathic pain. A common condition in both types of pain is mechanical allodynia: externally applied innocuous gentle touch becomes painful.
Project Summary Two of the most fundamental questions of sensory neuroscience are: 1) how is stimulus information represented by the activity of populations of neurons at different levels of information processing? and 2) what features of this activity are read at the next levels of neural processing to guide behavior? The first question has been the subject of a large body of work across different sensory stimuli. To answer the second question, one needs to establish a causal link between neuronal activity and behavior.
PROJECT SUMMARY Sensory perception involves processing incoming sensory input and interpreting that information through rules generated from prior experience. Stimulus features need to be bound together to form more complex sensory representations and then associated with a valence or action outcome to give meaning to those representations. In the mammalian neocortex, the formation of sensory representations is believed to occur through processing that is distributed across several cortical areas.
Sensory processing is a way to understand neural circuits and their functions during behavior. Behavioral context strongly affects sensory processing. For example, a brief visual stimulus is easier to detect if it appears in a predictable spatial location. Attention to visual space strongly enhances neural and behavioral responses to stimuli in those locations, but the detailed neural mechanisms producing these effects remain unknown.
PROJECT SUMMARY We seek to better understand how the brain processes olfactory information by focusing on how circuits of the olfactory bulb control two fundamental aspects of sensory processing: the relationship between sensory input and olfactory bulb output as a function of stimulus intensity, and tuning of response specificity by lateral inhibition.
Abstract Motion detection, a fundamental computation of the visual system, begins in the retina. In the mammalian retina, the direction of moving objects is computed by the direction-selective circuit. The retinal output of this circuit is provided by direction-selective ganglion cells (DSGCs). These cells are strongly activated by motion in their preferred direction, but are suppressed by motion in the opposite, or “null”, direction.
