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Stop Animal Exploitation NOW!
S. A. E. N.
"Exposing the truth to wipe out animal experimentation"

Government Grants Promoting Cruelty to Animals

Johns Hopkins University, Baltimore, MD

STEVEN S. HSIAO - Primate Testing - 2006

Grant Number: 5R01NS018787-24
Project Title: Cortical Processing of Tactual Spacial Information
PI Information: PROFESSOR STEVEN S. HSIAO, [email protected]

Abstract: DESCRIPTION (provided by applicant):
The broad, long-term aim of this study is to understand the neural mechanisms of tactile spatial perception in the human hand. Impaired tactile acuity leads to the inability to perform simple tasks such as buttoning and unbuttoning a button. Tactile spatial acuity is impaired in advanced age and in many neurological conditions. Understanding the underlying mechanisms is an essential first step in any treatment. The long-term aim of the study proposed here is to understand the neural mechanisms of tactile spatial perception in primary somatosensory (SI) cortex. A basic problem is that the functional organization of SI cortex is not well understood and this makes it difficult to formulate and test specific hypotheses. Combined psychophysical and neurophysiological studies over the last forty years have lead us to understand that the human hand is innervated by four types of mechanoreceptors and that each is responsible for a distinctly different aspect of tactile perception. Despite the distinct functional division evident in the peripheral nerve and despite the widespread, and justified belief that the information conveyed by the four afferent groups remains segregated within the central nervous system, the division of function within SI cortex is understood only in very broad terms. One reason is the lack of flexible, controlled stimuli with which to study the functions of neurons in St cortex, which we believe we have overcome with the development of a tactile stimulator with 400 independently controlled probes. Experiments proposed in Aim 1 examine the response properties of neurons in areas 3a, 3b, 1, and 2 of macaque SI cortex with temporal and spatial stimuli selected to span a wide range of tactile function. Experiments proposed in Aim 2 examine differences in the mechanisms underlying neuronal response properties in these areas using random stimuli and regression analyses. Experiments proposed in Aim 3 examine the neural mechanisms of tactile spatial perception with stimuli that have been particularly effective in previous studies (square-wave gratings) and with a new class of stimuli that combine the spatial and temporal properties of tactile function in a single framework (spatiotemporal sinusoids).

Thesaurus Terms:
neural information processing, psychophysics, somesthetic sensory cortex, space perception, touch
attention, form /pattern perception, motion perception, neuron, neurophysiology, proprioception /kinesthesia, sensory discrimination, somatic afferent nerve, stimulus /response
Macaca mulatta, behavior test, behavioral /social science research tag, clinical research, human subject, statistics /biometry

Institution: JOHNS HOPKINS UNIVERSITY
W400 Wyman Park Building
BALTIMORE, MD 212182680
Fiscal Year: 2006
Department: NONE
Project Start: 01-APR-1983
Project End: 28-FEB-2008
ICD: NATIONAL INSTITUTE OF NEUROLOGICAL DISORDERS AND STROKE
IRG: IFCN

The Journal of Neuroscience, December 8, 2004, 24(49):11193-11204

Receptive Field Properties of the Macaque Second Somatosensory Cortex: Evidence for Multiple Functional Representations

Paul J. Fitzgerald, John W. Lane, Pramodsingh H. Thakur, and Steven S. Hsiao

Zanvyl Krieger Mind/Brain Institute, Departments of Neuroscience and Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21218

Subjects.
Five cortical hemispheres of three rhesus monkeys (M. mulatta), weighing 5-7 kg, were studied. Two of the monkeys were male (monkeys 16H and R1171), and one was female (monkey 2H). We recorded from both hemispheres of monkeys 16H and 2H and from the right hemisphere of monkey R1171 in the mapping study and from both hemispheres of monkeys 16H and 2H in the motorized oriented bar study.

All of the recordings were done while the monkeys were in a nearly constant state of alertness. Two monkeys (16H and 2H) were trained to perform a visual detection task. In this task, the monkey pressed a lever with its foot to obtain a liquid reward when a 2 x 2� box, presented on a video monitor, dimmed for 1.5 sec after a random interval of 2-5 sec. The monkeys required 2-3 months of training to perform the task at 90% correct or better. The third monkey (R1171) was kept alert by giving it food treats at regular intervals.

Monkeys 16H and 2H were also trained to sit still with their hands restrained during recording sessions that used the motorized oriented bar. The palm of each hand was secured to a hand-holding base using custom-molded thermoplastic (Smith & Nephew, Memphis, TN). The individual fingers were then secured by gluing (PIC/PIC Apart; MCM Electronics, Centerville, OH) the fingernails to the base. When fully secured, the hand was supinated with the glabrous skin of digits 2-5 (D2-D5) exposed and these digits extending straight forward. Restraining the hand allowed the stimulator to stimulate the digits in an accurate and repeatable manner. Digit 1 was not studied using the stimulator because it was not possible to comfortably hold this digit flat against the hand-holder.

Surgery.
Before the microelectrode recordings, surgery was performed to secure a head-holding device and recording chambers to the skull. Surgical anesthesia was induced with ketamine HCl (20 mg/kg, i.m.) and maintained with pentobarbital (10-25 mg � kg-1 � hr-1, i.v.). All surgical procedures were done under sterile conditions and in accordance with the rules and regulations of the Johns Hopkins Animal Care and Use Committee and the Society for Neuroscience.

General recording techniques.
All recordings were performed with the monkeys in an awake, unanesthetized state.

Please email: STEVEN S. HSIAO, [email protected] to protest the inhumane use of animals in this experiment. We would also love to know about your efforts with this cause: [email protected]

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Rats, mice, birds, amphibians and other animals have been excluded from coverage by the Animal Welfare Act. Therefore research facility reports do not include these animals. As a result of this situation, a blank report, or one with few animals listed, does not mean that a facility has not performed experiments on non-reportable animals. A blank form does mean that the facility in question has not used covered animals (primates, dogs, cats, rabbits, guinea pigs, hamsters, pigs, sheep, goats, etc.). Rats and mice alone are believed to comprise over 90% of the animals used in experimentation. Therefore the majority of animals used at research facilities are not even counted.