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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

University of Minnesota, Minneapolis, MN

CLAUDIA M. HENDRIX - Primate Testing - 2006

Grant Number: 5F32NS047798-03
Project Title: Neuronal Encoding of Power Versus Precision Grasp
PI Information: CLAUDIA M. HENDRIX, [email protected] 

Abstract: DESCRIPTION (provided by applicant):
This proposal examines the neural control representation of reach-to-grasp in non-human primates. The neuronal coding of reach-to-grasp in the primary motor cortex, M1, and the ventral premotor cortex, PMv, will be examined within the context of a widely accepted categorical scheme for prehensile movements; power versus precision grasp. Although deeply embedded in the literature and researchers' theoretical framework, there is limited support for a central representation of a precision versus power categorical scheme. The objective of this grant proposal is to provide evidence that power and precision grasps lie on a continuum of hand shaping control strategies rather than as two distinct control strategies. The general hypothesis of a prehensile continuum will be tested via four specific aims: i) investigate the effects of object constraint on grasp type, ii) demonstrate that power and precision grasps will vary systematically along a 2-dimensional continuum of hand shape and grasp force, iii) fully explore the relationship between force production and hand shaping, and iv) demonstrate that representations of a prehensile continuum are found in both PMv and M1. Cell modulations, kinematic and kinetic variables, and EMG muscle activity will be recorded and analyzed. This research will provide insight into the control mechanisms involved in highly complex prehensile movements. These findings can be translated into clinically relevant terms for the habilitation/rehabilitation of neurological patients with motor control impairments.

Thesaurus Terms:
body movement, hand, motor cortex, muscle strength, neuron
biomechanics, central nervous system, muscle function, psychomotor function Macaca mulatta, electromyography, neuropsychological test, postdoctoral investigator, statistics /biometry

Fiscal Year: 2006
Project Start: 01-JAN-2004
Project End: 31-DEC-2006

J Neurophysiol 91: 2826-2837, 2004. First published February 4, 2004

Monkey Hand Postural Synergies During Reach-to-Grasp in the Absence of Vision of the Hand and Object

Carolyn R. Mason1, Lalin S. Theverapperuma2, Claudia M. Hendrix1 and Timothy J. Ebner1

Departments of 1Neuroscience and 2Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455
Submitted 8 July 2003; accepted in final form 28 January 2004

Two rhesus monkeys (1 female, G, at 5.2 kg, 1 male, L, at 6.8 kg) were trained to reach and grasp objects with an overhand power grasp using specific force levels. Monkey L was trained using its right hand on 15 objects, and monkey G was trained using its left hand on 16 objects. Both monkeys had been performing the task for 2 yr (monkey G for 2 yr and monkey L for 3 yr). The extra object was a small cube and required a pinch grasp. The animals sat in a primate chair with their heads fixed and facing a computer monitor (Fig. 1). The animals initiated a trial by placing their hand on a start pad located by their side while exerting a force for a randomized period (11.5 s). A red box and two blue bars would then appear on the monitor. The red box was a go cue that signaled the animals to reach (15 cm) and grasp the target object. The two blue bars indicated the force window within which the monkeys were to maintain the grasp force during the static portion of object grasp (i.e., target object hold). A red slider bar provided visual feedback to the monkeys of the grasp force being generated. If the monkey successfully maintained the specified force level for 1.5 s, it received a juice reward. At the completion of 25 successful trials, the object was changed. The monkeys were not able to see their hands or the objects. However, prior to initiating the first trial of each block, the animals were allowed to touch the target object. Therefore the animals were informed of the target object to be used before initiating a new block of trials. The number of trials needed for the monkey to adapt its hand posture to the new object was not explicitly analyzed. However, the over-training of the monkeys and their a priori knowledge (through touch) of which new object was being presented resulted in little or no adaptation period during the actual data collection period. Behavioral data collected included specified force level, force generated, and timing information.

Please email: CLAUDIA M. HENDRIX, [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.

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