University of Arizona, Tucson, AZ

Home Page
About SAEN
Articles and Reports
Contact Us
Events and Campaigns
Fact Sheets
Financial Information
How You Can Help
Make a Donation, Please!
Media Coverage
Newsletters
Petitions
Picture Archive
Press Releases
Resources and Links
Grass Roots Org. List

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

Government Grants Promoting Cruelty to Animals

University of Arizona, Tucson, AZ

KATALIN M. GOTHARD - Primate Testing - 2006

Grant Number: 5R01MH070836-02
Project Title: Neural Encoding of Emotion in the Primate Amygdala
PI Information: KATALIN M. GOTHARD, kgothard@email.arizona.edu 

Abstract: DESCRIPTION (provided by applicant): The neural substrate of emotion encompasses a large brain circuit in which the amygdala plays a key role. The long-term goal of the proposed research is to determine how specific functions attributed to the amygdala are carried out at the neural level. One of the functions of the amygdala is to select from the environment stimuli with inherent emotional value and respond to them adequately, e.g., withdraw or fight when threatened. This process might rely on innately programmed and relatively inflexible pathways to ensure enduring and reliable reactions in response to objects and events of survival value. In parallel, the amygdala is required to update the reinforcing value of many stimuli that gain or lose emotional significance through learning and experience. Both functions are used for social behavior. The intricacy of primate societies requires that humans and monkeys respond reliably to facial expressions and other signals with emotional significance but also to adjust responses to social context or to the history of interactions between individuals. The neural basis of these complex and diverse functions are largely unknown. The central hypothesis of this proposal is that the lateral, basal, and central amygdaloid nuclei carry out a sequence of dissociable but complementary functions. The objective of the proposed studies is to identify in the amygdala the neural signature of stimulus differentiation, evaluation, and the initiation of emotional responses. This will be achieved by relating autonomic, behavioral, and neural ensemble responses to manipulations of the reinforcing value of face and non-face stimuli. This approach will determine (1) whether negative or positive stimuli are processed preferentially or differentially in the amygdala, (2) whether facial expressions that carry inherent positive or negative valence engage the same neuronal processes as neutral objects paired with reward or punishment, (3) whether neural activity in the amygdale predicts the autonomic and somatic expressions of emotion. These studies will determine the neural mechanism by which the amygdala evaluates stimuli of significance and relays the results of this process to a complex brain circuits that control emotional and social behavior. Understanding the neural processes carried out at each level of this circuit holds promise for more effective interventions in emotional disorders.

Thesaurus Terms:
amygdala, association learning, brain electrical activity, emotion, face expression, neural information processing, neuroanatomy, reinforcer, social behavior, visual stimulus
autonomic nervous system, brain imaging /visualization /scanning
Macaca mulatta, electrode

Institution:
UNIVERSITY OF ARIZONA
PO BOX 3308
TUCSON, AZ 857223308
Fiscal Year: 2006
Department: PHYSIOLOGY
Project Start: 01-JAN-2005
Project End: 31-DEC-2009
ICD: NATIONAL INSTITUTE OF MENTAL HEALTH
IRG: COG

Neural Responses to Facial Expression and Face Identity in the Monkey Amygdala

K. M. Gothard1, F. P. Battaglia2, C. A. Erickson3, K. M. Spitler1 and D. G. Amaral4

1Department of Physiology, College of Medicine, The University of Arizona, Tucson, Arizona; 2Graduate School of Neurosciences Amsterdam, Faculty of Science, Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands; 3Helen Wills Neuroscience Institute, University of California–Berkeley, Berkeley; and 4Department of Psychiatry and Behavioral Sciences, The California National Primate Research Center and The Music Intelligence Neural Development Institute, University of California–Davis, Sacramento, California

Submitted 12 July 2006; accepted in final form 2 November 2006
J Neurophysiol 97: 1671-1683, 2007

Surgical procedures
All surgical procedures were carried out in compliance with National Institutes of Health guidelines and were approved by the IACUC at the University of Arizona. Two adult male rhesus monkeys (Macaca mulatta) (monkeys S and H) were surgically prepared for multielectrode recordings from the amygdala using a two-step surgical procedure. For both surgical procedures the monkeys were preanesthetized with ketamine (10–15 mg/kg), administered intramuscularly, and brought to surgical levels of anesthesia with isoflurane (1–1.5%) supplemented with fentanyl (7–10 µg • kg–1 • h–1). During the first procedure, monkeys were implanted with three titanium tripod plates, custom-manufactured by Thomas Recording (Giessen, Germany). Each tripod plate had an elevated center with a threaded screw hole and three flat radial support arms emerging at 120° intervals. The three support arms were 10 mm long, 2 mm wide, and were perforated at the end to accommodate a 2-mm-diameter bone screw. The arms were bent to match the curvature of the skull and affixed to the bone with screws. Two plates were affixed posteriorly, 15 mm lateral from midline and approximately 20 mm posterior from the interaural line. The third plate was affixed straddling the midline 2 cm anterior to the interaural line. The temporalis muscle and the scalp were closed over the plates and the bone was allowed to heal and grow around the plates (about 4–12 mo). Once substantial bone growth had occurred around the screws and the arms of the plates (verified by CT scan), the second procedure was undertaken in which the scalp above the plates was perforated and small threaded head posts (3-mm-diameter shaft, 15-mm length, 5-mm-diameter spherical head) were screwed into the center of each of the tripod plates. The posts served as anchors for a removable stainless steel ring that was secured in a rigid frame during experiments. Such an arrangement distributed the torque generated by head immobilization across the three head posts.
During the second surgical procedure, a recording chamber was secured with bone screws and bone cement to the skull above the amygdala. The chamber was placed at stereotaxic coordinates calculated from a structural MRI carried out before surgery. Magnetic search coils were also implanted in the left eye of one of monkey (S) following standard procedures (Judge et al. 1980 ; Robinson 1963 ). After a 10-day recovery period, monkeys were trained to tolerate head immobilization and to fixate on objects presented on a computer monitor. When behavioral training was complete, a 6- to 8-mm-diameter craniotomy was performed within the chamber.

Behavioral training
The monkeys were trained to fixate on a white square that subtended 0.5 degree of visual angle (dva). The eye movements of monkey S were tracked with a resolution of 0.25 dva and were digitized at 500 Hz using an analog eye tracker (DNI, Newark, DE). Eye movements of monkey H were monitored with the infrared eye tracker (Iscan, Burlington, MA) with a resolution of 0.5 dva. Both eye trackers were connected to the CORTEX experimental control system (NIMH-supported freeware from the website: http://www.cortex.salk.edu) . When the eyes were fixated for 150 ms at the white square, the fixation icon was removed from the monitor and a stimulus image, subtending 12 dva, was displayed. The monkeys were allowed to freely scan the image, with the requirement to maintain gaze within the boundaries of the image. If this requirement was met for the entire duration of the display (500 ms or 1 s) the monkeys received a 0.5- to 1-ml reward droplet. The reward consisted of a paste of mashed granola, rice cereal, and fruit juice or simple fruit juice mixed with applesauce. To disambiguate the effect of the reward from the effect of the stimuli, monkeys received a reward on only 50% of the trials, so that each image was followed an equal number of times by reward or no reward. The duration of the intertrial interval (ITI) was 1 s. When the monkey's eyes moved outside the boundary of the image, the trial was terminated by removing the image from the monitor. Error trials were not rewarded and were followed by a 2-s time-out period. Error trials were excluded from the analysis. To prevent habituation and blunting of the emotional response to face stimuli, the sets of images used for training or used during the period when we searched for neurons in the amygdala did not contain monkey faces or images intended for presentation during neurophysiological recordings.

Please email:  KATALIN M. GOTHARD, kgothard@email.arizona.edu to protest the inhumane use of animals in this experiment. We would also love to know about your efforts with this cause: saen@saenonline.org

Return to Grants
Return to University of Arizona, Tucson, AZ
Return to Facility Reports and Information
Return to Resources and Links

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.

We welcome your comments and questions

(d-9)


This site is hosted and maintained by:
The Mary T. and Frank L. Hoffman Family Foundation
Thank you for visiting all-creatures.org.
Since date.gif (991 bytes)