Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Effects of morphine and pentobarbital on conditioned electrodermal responses and basal conductance in man

  • 12 Accesses

  • 3 Citations


The effects of morphine (8 mg and 16 mg/70 kg) and pentobarbital (200 mg/70 kg) upon acquisition of a conditioned electrodermal response were studied. Both morphine (16 mg) and pentobarbital tended to reduce the degree of conditioning. In addition, morphine (16 mg) attenuated the increase in basal conductance relative to that which occurred under placebo during the conditioning period and did so more effectively than pentobarbital. Pentobarbital, but not morphine, decreased basal conductance under the non-shock condition. Morphine thus acted selectively on the effects of shock on basal conductance, and thereby, possibly, on anxiety. Neither morphine nor pentobarbital appeared to impair responsivity of the phasic EDR.

The tentative hypothesis was offered that the tonic and phasic reactions of the electrodermogram are separately mediated and that morphine has a greater effect upon the neural basis for the tonic than for the phasic reaction.

This is a preview of subscription content, log in to check access.


  1. Becker, W. C., and H. H. Matteson: GSR conditioning, anxiety and extroversion. J. abnorm. soc. Psychol. 62, 427–430 (1961).

  2. Beecher, H. K.: The measurement of pain. Pharmacol. Rev. 9, 59–209 (1957).

  3. Benzinger, T. H.: On physical heat regulation and the sense of temperature in man. Proc. nat. Acad. Sci. (Wash.) 45, 645–659 (1959).

  4. Dureman, I.: Drugs and autonomic conditioning. Acta Acad. Reg. Sci. Upsaliensis 4, 1–162 (1959).

  5. Hill, H. E., R. E. Belleville, and A. Wikler: Reduction of painconditioned anxiety by analgesic doses of morphine in rats. Proc. Soc. exp. Biol. (N. Y.) 86, 881–884 (1954).

  6. —, C. H. Kornetsky, H. G. Flanary, and A. Wikler: Effects of anxiety and morphine on discrimination of intensities of painful stimuli. J. clin. Invest. 31, 473–480 (1952).

  7. Kissel, S., and L. W. Littig: Test anxiety and skin conductance. J. abnorm. soc. Psychol. 65, 276–278 (1962).

  8. Kornetsky, C. H.: Effects of anxiety and morphine on the anticipation and perception of painful radiant thermal stimuli. J. comp. physiol. Psychol. 47, 130 bis 132 (1954).

  9. Mitchell, L. E., and M. Zax: The effects of chlorpromazine on GSR conditioning. J. abnorm. soc. Psychol. 59, 246–249 (1959).

  10. Obrist, P. A.: GSR conditioning and anxiety as measured by basal conductance. Paper presented at the Eastern Psychological Meeting, Philadelphia, Pa., 11 April 1958.

  11. Rutledge, L. T., and R. W. Doty: Differential action of chlorpromazine on reflexes conditioned to central and peripheral stimulation. Amer. J. Physiol. 191, 189–192 (1957).

  12. Schaumann, O.: Some new aspects of the action of morphinelike analgesics. Brit. med. J. 11, 1091–1093 (1956).

  13. Schneider, R. A., and J. P. Costiloe: Effect of centrally active drugs on conditioning in man. Amer. J. med. Sci. 233, 418–423 (1957).

  14. Sharpless, S., and H. Jasper: Habituation of the arousal reaction. Brain 79, 655–680 (1956).

  15. Spence, K. W.: A theory of emotionally based drive (D) and its relation to performance im simple learning situations. Amer. Psychologist 13, 131–141 (1958).

  16. Welch, L., and J. Kubis: The effect of anxiety on the conditioning rate and stability of the PGR. J. Psychol. 23, 83–91 (1947).

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Jones, B.E., Ayres, J.J.B., Flanary, H.G. et al. Effects of morphine and pentobarbital on conditioned electrodermal responses and basal conductance in man. Psychopharmacologia 7, 159–174 (1965).

Download citation


  • Placebo
  • Morphine
  • Pentobarbital
  • Phasic Reaction
  • Neural Basis