Abstract

The goal of this proposal is to study how auditory information is integrated with visual information to generate purposeful orienting responses. We propose to study this sensorimotor integration in the superior colliculus (SC) using physiological recordings in behaving cats trained to saccade to visual and acoustic targets, and light and electron microscopic neuroanatomical techniques. The PI of this project is a New Investigator. An essential premise of this proposal is that important elements of the current model of sensorimotor integration in the SC of the cat are based on data from anesthetized cats, and anesthetics profoundly affect the physiology of SC neurons. One of the building blocks of this model, the enhancement of SC responses to bimodal (visual + auditory) stimuli, is thought to be a mechanism to increase the likelihood of behavioral responses to relevant stimuli. Our preliminary findings in the behaving cat do not reveal enhancement of SC units under experimental conditions similar to those used in studies of the anesthetized preparation. Accordingly, in Specific Aim number 1 we propose to complete our studies of SC single unit responses to unimodal and bimodal (auditory, visual) stimuli in the standard-trained cat. We will test our hypothesis that enhancement results from spurious effects of anesthetics in Specific Aim number 2 by recording from the same SC units under both behaving and anesthetized conditions. Our hypothesis that sodium pentobarbital affects inhibitory inputs to the SC will be tested in Specific Aim number 3, where we will chemically deactivate the major source of inhibitory input to the SC, the substantia nigra pars reticulata (Snr).
Specific Aim number 4 will determine if the behavioral relevance of sensory stimuli can lead to enhancement of the SC of the specially-trained behaving cat, while Specific Aim numbers 5, 6, and 7 are designed to explore the inputs to the SC that might underlie sensorimotor integration of auditory-related information.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
5R01DC003693-03
Application #
6379429
Study Section
Special Emphasis Panel (ZRG1-IFCN-5 (01))
Project Start
1999-09-01
Project End
2003-08-31
Budget Start
2001-09-01
Budget End
2002-08-31
Support Year
3
Fiscal Year
2001
Total Cost
$148,162
Indirect Cost

  Institution

Name
University of Wisconsin Madison
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
161202122
City
Madison
State
WI
Country
United States
Zip Code
53715

  Publications

Rajala, Abigail Z; Jenison, Rick L; Populin, Luis C (2015) Decision making: effects of methylphenidate on temporal discounting in nonhuman primates. J Neurophysiol 114:70-9
Rajala, Abigail Z; Zaitoun, Ismail; Henriques, Jeffrey B et al. (2014) Dopamine transporter gene susceptibility to methylation is associated with impulsivity in nonhuman primates. J Neurophysiol 112:2138-46
Rajala, Abigail Z; Yan, Yonghe; Dent, Micheal L et al. (2013) The inferior colliculus encodes the Franssen auditory spatial illusion. Eur J Neurosci 38:3056-70
Rajala, Abigail Z; Henriques, Jeffrey B; Populin, Luis C (2012) Dissociative effects of methylphenidate in nonhuman primates: trade-offs between cognitive and behavioral performance. J Cogn Neurosci 24:1371-81
Populin, Luis C; Rajala, Abigail Z (2011) Target modality determines eye-head coordination in nonhuman primates: implications for gaze control. J Neurophysiol 106:2000-11
Populin, Luis C; Rajala, Abigail Z (2010) Time course of allocation of spatial attention by acoustic cues in non-human primates. Eur J Neurosci 32:1040-8
Rajala, Abigail Z; Reininger, Katharine R; Lancaster, Kimberly M et al. (2010) Rhesus monkeys (Macaca mulatta) do recognize themselves in the mirror: implications for the evolution of self-recognition. PLoS One 5:
Populin, Luis C (2008) Human sound localization: measurements in untrained, head-unrestrained subjects using gaze as a pointer. Exp Brain Res 190:11-30
Populin, Luis C (2006) Monkey sound localization: head-restrained versus head-unrestrained orienting. J Neurosci 26:9820-32
Populin, Luis C (2005) Anesthetics change the excitation/inhibition balance that governs sensory processing in the cat superior colliculus. J Neurosci 25:5903-14

Showing the most recent 10 out of 13 publications