Abstract
In Experiment I, four groups of 24 rats each were presented with 200, 120-db tones at an 8-sec interstimulus interval (ISI) on each of 2 days following intraperitoneal injections of saline or 15 mg/kg N-N-Dimethyltryptamine (DMT). Separate groups were injected with either saline on both days or DMT on both days or saline on Day 1 and DMT on Day 2 or DMT on Day 1 and saline on Day 2. DMT depressed startle likelihood and impaired 24-h retention of startle habituation. The reduction in startle amplitude was monotonically related to the dose of DMT that was given over doses of 1, 2, 4, 8, and 16 mg/kg (Experiment II) and the impairment of retention was monotonically related to the dose of DMT that was given over doses of 1, 4, and 16 mg/kg (Experiment III). DMT did not impair retention of startle habituation if a 30-sec rather than an 8-sec ISI was used during training and testing (Experiment IV).
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Abel, E. L.: Retrieval of information after use of marihuana. Nature (Lond.) 231, 58 (1971a).
—: Marihuana and memory: Acquisition or retrieval. Science 173, 1038–1040 (1971b).
Aghajanian, G. K., Foote, W. E., Sheard, M. H.: Action of psychotogenic drugs on single midbrain raphé neurons. J. Pharmacol. exp. Ther. 171, 178–187 (1970).
Armus, H. L., Carlson, K. R., Guinan, J. F., Crowell, R. A.: Effect of a secondary reinforcement stimulus on the auditory startle response. Psychol. Rep. 14, 535–540 (1964).
Bridger, W. H., Mandel, I. J.: The effects of dimethoxyphenylethylamine and mescaline on classical conditioning in rats as measured by the potentiated startle response. Life Sci. 6, 775–781 (1967).
Brimblecombe, R. W.: Effects of psychotropic drugs on open field behaviour in rats. Psychpharmacologia (Berl.) 4, 139–147 (1963).
Brown, J. S., Kalish, H. I., Farber, I. E.: Conditioned fear as measured by magnitude of startle response to an auditory stimulus. J. exp. Psychol. 41, 317–328 (1951).
Chi, C. C.: The effect of amobarbital sodium on conditioned fear as measured by the potentiated startle response in rats. Psychopharmacologia (Berl.) 7, 115–122 (1965).
Davis, M.: Effects of interstimulus length and variability on startle-response habituation in the rat. J. comp. physiol. Psychol. 72, 177–192 (1970).
—: Differential retention of sensitization and habituation of the startle response in the rat. J. comp. physiol. Psychol. 78, 260–267 (1972).
Groves, P. M., Thompson, R. F.: Habituation: A dual process theory. Psychol. Rev. 77, 419–450 (1970).
Horlington, M.: Startle response circadian rhythm in rats: Lack of correlation with motor activity. Physiol. Behav. 5, 49–53 (1970).
Key, B. J.: Effects of chlorpromazine and lysergic acid diethylamide on the rate of habituation of the arousal response. Nature (Lond.) 190, 275–277 (1961).
—: The effect of LSD-25 on the interaction between conditioned and nonconditioned stimuli in a simple avoidance situation. Psychopharmacologia (Berl.) 6, 319–326 (1964).
—, Bradley, P. B.: The effects of drugs on conditioning and habituation of arousal stimuli in animals. Psychopharmacologia (Berl.) 1, 450–462 (1960).
Nadel, L.: Cortical spreading depression and habituation. Psychon. Sci. 5, 119–120 (1966).
Overton, D. A.: State-dependent or “dissociated” learning produced with pentobarbital. J. comp. physiol. Psychol. 57, 3–12 (1964).
Smythies, J. R., Bradley, R. J., Johnston, V. S., Leonard, F.: The behavioral effects of some derivatives of mescaline and N,N-dimethyltryptamine in the rat. Life Sci. 6, 1887–1893 (1967).
Szara, S.: Dimethyltryptamine: Its metabolism in man: The relation of its psychotic effect to serotonin metabolism. Experientia (Basel) 12, 441–442 (1956).
Thompson, R. F., Welker, W. I.: Role of auditory cortex in reflex head orientation by cats to auditory stimuli. J. comp. physiol. Psychol. 56, 996–1002 (1963).
Uyeno, E. T.: Lysergic acid diethylamide and a novel stimulus. Psychon. Sci. 18, 52 (1970).
Warburton, D. M., Groves, P. M.: The effects of scopolamine on habituation of acoustic startle response in rats. Commun. Behav. Biol. 3, 289–293 (1969).
Zimmerberg, B., Glick, S. D., Jarvik, M. E.: Impairment of recent memory by marihuana and THC in Rhesus monkeys. Nature (Lond.) 233, 343–345 (1971).
Author information
Authors and Affiliations
Additional information
This research was supported in part by Research Grants MH-13917 and MH-07114 from the National Institute of Mental Health and Grant GB-23685 from the National Science Foundation, and by the State of Connecticut. We are most grateful to Lee Schulhof for her help in running animals and statistical analysis.
Rights and permissions
About this article
Cite this article
Davis, M., Bear, H.D. Effects of N-N-Dimethyltryptamine on retention of startle response habituation in the rat. Psychopharmacologia 27, 29–44 (1972). https://doi.org/10.1007/BF00421954
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF00421954