Theory & Data Analysis Tools

Project Summary There is no dedicated sensory organ for time, and yet our brains are able to use time to anticipate the environment and adapt. The process of interval timing on a seconds to minutes scale is evolutionarily widespread and is central to critical cognitive tasks and behaviors, including how to optimally find food. Despite the importance of this ability, there is no known neural mechanism for interval timing on this scale in any organism.

Project Summary Integration of sensory information with motor commands allows movement to be adaptable. For example, many survival-critical orofacial behaviors (chewing, drinking, breathing, etc.) involve updating movement trajectories based on interaction with objects (e.g. matching chewing patterns to food material properties). Proprioceptors, which are sensory afferents that provide information about body position, likely play critical roles in this process.

Project Summary / Abstract Ascertaining the neural basis of behavior has been a cornerstone goal since the conception of neurobiology. While activity recording and loss-of-function studies have shed light on brain regions involved and necessary for the expression of certain behaviors, they are unable to determine the information each circuit is responsible for encoding.

PROJECT SUMMARY/ABSTRACT The basal ganglia are a group of deep brain nuclei that play a central role in motivating, selecting, and learning actions. The largest of these nuclei, the striatum, serves as the principal input, receiving widespread convergent excitatory innervation from cortex and thalamus, as well as dopamine (DA) inputs from the midbrain.

Project Summary The overall premise of this proposal is to understand how the transformation of the signals from proprioceptive afferents within muscles leads to the representation of movements in somatosensory cortex. Proprioception is a fundamental part of the neural control of movement, evidenced by extreme movement impairments in individuals with proprioceptive loss.

PROJECT SUMMARY Stroke-causing illness, disability, and early death is set to double worldwide within the next 15 years. Despite physical therapy, about 50% of stroke survivors have impaired hand function, which strongly impacts activities of daily living and independence; novel treatment methods are urgently required. One of many predictors of chronically impaired hand function includes deficits in somatosensation.

PROJECT SUMMARY A major unresolved question in systems neuroscience is whether specialized anatomical structures support specific functions in behavior. Therefore, this proposal will bridge the gap between anatomical circuit diagrams and their predicted functional roles. Specifically, it will address the functional consequences of the patch/matrix-like “modular” anatomical organization that has recently been characterized in the inferior colliculus.

Perceptual decision-making is a complex cognitive function critical for health, reproductive success, and survival. In this process, an informed choice based on sensory evidence is made through engagement of circuits across the brain.

Project Summary/Abstract Recent evidence from multiple laboratories in both human and animal models supports a role for the granule cell (GrC) pathway of the cerebellum in representing a wide range of sensory, motor, and internal information. Classical theories of cerebellar function proposed that activity in a small number of GrCs (

Abstract Brain-computer interfaces (BCI) offer hope to treat otherwise intractable neurological disease. However, the current state of BCI is still short of the potential; solutions to fundamental biological and engineering problems must be found before BCIs can be broadly used for patient care. A collaborative group at UCSD has developed a high-density array of microelectrodes (microgrid) that surmounts many of the major hurdles facing neural interface devices.