A State-Dependent Learning Effect Produced by Amylobarbitone Sodium

Abstract

Learning is said to be state-dependent when a response which is learned in a given internal state shows disproportionate decrement in retention when the internal state of the learner is changed. Research on this phenomenon has a long history. It was first noted by investigators who were concerned with the problem of whether overt responses were necessary for the formation of classically conditioned responses. Curare was used to eliminate the overt response, and it was found that:

Asymmetrical Transfer: An Inherent Weakness of Repeated-Measure Drug Experiments

“…A more plausible explanation for the digit-span asymmetry is that the subject's state when first performing a task may determine subsequent perfor mance. This paradox can often be observed with a relatively complex task which is learned while sleep deprived or drugged: it is subsequently performed better when the subject is again in that state than in normal consciousness (Baddeley, 1976;Ley et al, 1972). Such ‘¿ state-dependent' learning effects may provoke asymmetries because subjects adopt different strategies for performing a difficult task, according to their particular state at the time.…”

“…of strategies, particularly for rehearsaland retrieval of the stimulus items- Hamilton and Hockey (1970) have shown changes in processing strategy as fatigue develops during memory span performance. Such changes might well be potentiated by a drug and it seems highly probable that once established they would endure into subsequent test sessions, obscuring the effects of other treatments or preventing improve ment with placebo (Ley et al, 1972). Relatively simple tasks are less likely to be affected (Millar and Wilkinson, 1981).…”

The cue-dependent nature of state-dependent retrieval

“…Studies of the state-dependent effects of drugs on autonomic responsivity (Crow & Ball, 1975;Hinrichsen, Katahn, & Levenson, 1974;Powell, Goodwin, Janes, & Hoine, 1971), motor learning (Goodwin, Powell, Bremer, Hoine, & Stern, 1969;Hinrichsen et al, 1974;Ley, Jain, Swinson, Eaves, Bradshaw, Kincey, Crowder, & Abbiss, 1972;Roffman, Marshall, Silverstein, Karkalas, Smith, & Lal, 1972), or operant discriminative avoidance (Goodwin et al, 1969;Hill, Schwin, Powell, & Goodwin, 1973) were considered to be beyond the purview of the paper, and therefore, they were excluded from consideration. Also excluded were experiments involving the tasks of verbal interference (viz., A-C and A-B r negative transfer; Tarter, 1970), "four-way picture choice" (Stillman, Weingartner, Wyatt, Gillin, & Eich, 1974), learning of neologisms (Ley et al, 1972), serial anticipation (Ley et al, 1972; Storm, Caird, & Korbin, Note 1), serial reconstruction (Hill et al, 1973;Stillman et al, 1974), and word association reproduction (Crow & Ball, 1975;Goodwin et al, 1969;Hill et al, 1973;Weingartner & Faillace, 1971). These six tasks have been used too infrequently (only one or two cases pertaining to each, except word association reproduction, which counts a total of four relevant cases) to allow accurate assessment of their sensitivity as instruments for detecting the occurrence of state dependence-a point to be taken up later in the paper (also see Footnote 8).…”

Neurobiological correlates of state-dependent context fear

“…Some of the earliest evidence for state-dependent learning comes from studies with compounds that are known GABAR agonists or positive allosteric modulators, including alcohol (Goodwin et al 1969;Hinrichsen et al 1974;Weingartner et al 1976), amobarbital (Ley et al 1972), anddiazepam (Jensen et al 1989), all of which bind to multiple GABA A R subunits. Various GABA A R agonists have been tested for the ability to support state-dependent conditioned fear memory, however they have proven ineffective (Davis 1979).…”