Variations in retrograde amnesia with parameters of electroconvulsive shock and time of testing.

Abstract

ECS OF 35 OR 100 MA. FOR .2 OR .5 SEC. WAS ADMINISTERED TO MALE RATS 3.1-3000 SEC. AFTER A SINGLE STEP-DOWN PASSIVE AVOIDANCE TRIAL. LENGTH OF RETROGRADE AMNESIA (RA) MEASURED 24 HR. LATER VARIED WITH ECS CURRENT, BUT NOT WITH ECS DURATION: 35-MA ECS CAUSED RA OF 30 SEC., WHEREAS 100-MA ECS CAUSED RA OF 50 MIN. A FURTHER RETEST 48 HR. AFTER LEARNING REVEALED INCREASED RETENTION; THE GRADIENT OF RA, WHICH WAS LOGARITHMIC 24 HR. AFTER LEARNING, APPROXIMATED A STEP FUNCTION WITH A DISCONTINUITY BETWEEN 3 AND 30 SEC.; AVERSIVENESS OF A SINGLE ECS, WHICH WAS NEGLIGIBLE AT 24 HR., HAD BECOME SIGNIFICANT. (17 REF.) (PsycINFO Database Record (c) 2006 APA, all rights reserved)