18. GOALSFORFELLOWSHITPRAININGANDCAREER I have three primary goals for my fellowship training. First, I want to study neural processing from a different perspective than I have previously. My doctoral work was in a lab that studies visual processing in the context of two ocular behaviors (smooth pursuit and the vestibulo- ocular reflex), while my current postdoctoral work is in a lab that is concerned with the neuronal mechanisms that underlie visual processing. For me, this will be a significant theoretical shift from studying the signals in the visual system that give rise to visual behavior, to studying the circuitry that gives rise to such visual signals. The second goal I have for my fellowship is to learn a new technique. My prior experience is in extracellular physiology in vivo and animal behavior; now I will learn the technique of intracellular recording in vivo to study synaptic connectivity and cellular function. My final goal is to clarify one of the sensory transformations that occurs in neurons of the prim_visual cortex V(V1): direction selectivity. _PONSOR 19. NAMEANDDEGREE(S) David Ferster, Ph.D. 20. POSITION/RANK Professor, Northwestern University 21.RESEARCIHNTERESTS/AREAS Central mechanisms of mammalian visual processing; Neuronal function of mammalian neocortex 22. DESCRIPTION (Do not exceed space provided) One strategy the brain uses to process information rapidly is the use of multiple parallel pathways to analyze different aspects of the world simultaneously. The analysis of a visual scene is thought to be segregated into three parallel pathways dedicated to the processing of color, shape, and motion. During this fellowship we will study the neuronal mechanisms that underlie the third pathway, motion selectivity, in visual cortex. Motion processing in V1 requires cortical neurons that respond selectively to the direction and speed of moving objects in the world. Direction selectivity is a neuronal response property that is created de novo in V1 neurons: it is not present in the neurons of the lateral geniculate nucleus (LGN) that provide visual input to the cortex. Unlike other purely spatial response properties such as orientation selectivity, direction selectivity requires processing in the time domain as well as the space domain: direction selective neurons must discern not only where an object is, but where it was in the previous moment. Direction selectivity is therefore thought to be created by combining inputs from LGN neurons with different receptive field positions and different temporal delays. We will investigate how the signals from the LGN are transformed and combined to give neurons in V1 their directionally selective responses. By studying and understanding direction selectivity, we will learn the rules of information processing that may apply generally to cortical processing of temporal information. PHS 416-1 (Rev. 12/98) Form Page 2 BB cc Individual NRSA Application Table of Contents ========================================Section End===========================================
| Priebe, Nicholas J; Lampl, Ilan; Ferster, David (2010) Mechanisms of direction selectivity in cat primary visual cortex as revealed by visual adaptation. J Neurophysiol 104:2615-23 |
| Priebe, Nicholas J; Ferster, David (2006) Mechanisms underlying cross-orientation suppression in cat visual cortex. Nat Neurosci 9:552-61 |
| Priebe, Nicholas J; Ferster, David (2005) Direction selectivity of excitation and inhibition in simple cells of the cat primary visual cortex. Neuron 45:133-45 |
