It is well-established that long-latency event-related brain potentials are elicited in both humans and experimental animals. These slow potentials are altered in a variety of psychiatric disorders and in the elderly. It has been suggested that such potentials reflect fundamental functional processes that are operational across several species. Indirect evidence suggests that these event-related slow potentials (ERSPs) reflect the activity of neuronal systems which mediate their effects via """"""""neurotransmitter"""""""" substances such as norepinephrine, dopamine, 5-hydroxytryptamine or acetylcholine. The long-term objective is to understand brain mechanisms of ERSP generation; the objective of this project is to determine whether or not cortical ERSPs are regulated by certain transmitters acting with the cortex. The principal approach involves determination of the effects on ERSPs of neurotoxin-induced lesions of transmitter input to the neocortex. ERSP effects of drugs which modify the activity of neuromodulator systems will also be examined. Neurophysiological recordings will be obtained in chronically-prepared, freely moving rats responding to an auditory cue preceding rewarding stimulation of the medial forebrain bundle. Appropriate stimulus parameters are determined by behavioral techniques (self-stimulation). To evaluate lesion effects, ERSPs will be recorded bilaterally following unilateral lesions of noradrenergic, dopaminergic, 5-hydroxytryptaminergic and cholinergic pathways to the cortex or localized neurotoxin injections. Effectiveness and specificity of the lesions will be ascertained by regional neurochemical analysis of monoamine content and uptake as well as choline acetyltransferase activity. Dose-response data will be obtained for evaluation of drug-induced alterations of the ERSPs.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Research Project (R01)
Project #
5R01MH029653-08
Application #
3375119
Study Section
(BPNB)
Project Start
1976-09-01
Project End
1987-02-28
Budget Start
1985-09-01
Budget End
1987-02-28
Support Year
8
Fiscal Year
1985
Total Cost
Indirect Cost
Name
Texas Tech University
Department
Type
Schools of Medicine
DUNS #
609980727
City
Lubbock
State
TX
Country
United States
Zip Code
79430
Pirch, J; Rigdon, G; Rucker, H et al. (1991) Basal forebrain modulation of cortical cell activity during conditioning. Adv Exp Med Biol 295:219-31
Rucker, H K; Corbus, M J; Pirch, J H (1986) Discriminative conditioning-related slow potential and single-unit responses in the frontal cortex of urethane-anesthetized rats. Brain Res 376:368-72
Pirch, J H; Corbus, M J; Rigdon, G C et al. (1986) Generation of cortical event-related slow potentials in the rat involves nucleus basalis cholinergic innervation. Electroencephalogr Clin Neurophysiol 63:464-75
Rigdon, G C; Pirch, J H (1986) Nucleus basalis involvement in conditioned neuronal responses in the rat frontal cortex. J Neurosci 6:2535-42
Pirch, J H; Corbus, M J; Ebenezer, I (1985) Conditioned cortical slow potential responses in urethane anesthetized rats. Int J Neurosci 25:207-18
Pirch, J H; Corbus, M J; Rigdon, G C (1985) Conditioning-related single unit activity in the frontal cortex of urethane anesthetized rats. Int J Neurosci 25:263-71