The Center for Alternatives to Animal Testing is an academic center affiliated with the Division of Toxicological Sciences in the Department of Environmental Health Sciences of the Johns Hopkins University Bloomberg School of Public Health.

 

Johns Hopkins School of Public Health

Research Grants 2007-2008

A Closed-Head Recording Device for Neurologic Studies in Laboratory Animals

Lisa Krugner-Higby, DVM, PhD
University of Wisconsin-Madison

Devices that can be surgically fixed to the heads of animals such as rats, cats or monkeys have been important tools to study the function of the nervous system. These experiments have contributed significantly to our knowledge of how the brain processes information from our eyes and optic nerves.  Similar experiments are also important in the study of diseases of the nervous system associated with aging, such as Alzheimer’s disease and Parkinson’s syndrome.  However, these devices pose very significant issues for the welfare of the animals.  ‘Head caps,’ as these devices are commonly called, can serve as a focus for infection because they leave portions of the nervous system open to the external environment.  Our laboratory has developed an electrode array for recording microEEG that can be used to form the basis of a fully-implantable system for studying the central nervous system.  The electrode array has been tested in animals in preliminary experiments.  The array will eventually be connected to an implantable telemetry device.  The telemetry device will receive electrical signals from the electrode array in contact with the membranous covering of the brain and transmit them as digitized information to a receiver linked to a computer and appropriate soft ware.  A fully-implantable system will not leave portions of nervous system open to the external environment and therefore vulnerable to infection.  This will provide a significant improvement in the welfare of animals used in neurological research.