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S E File

Publications and source records attributed to S E File.

At least 325 records · Page 18Linked to original sources
PubMed1977

Effects of N,N-dimethyltryptamine on behavioural habituation in the rat.

The processes involved in habituation and the various ways drugs might affect habituation are discussed. Exploration was measured in a holehoard and N,N-Dimethyltryptamine (DMT, 4 mg/kg) profoundly reduced the level of exploration, precluding any conclusions about the rate of habituation with this dose. However, both 2 and 4 mg/kg doses prevented the 24-hr retention of habituation of exploration. DMT (2 and 4 mg/kg) did not reduce the initial distraction to a tone stimulus, but the rate of habituation and its 24-hr retention was impaired.

Animals↗
PubMed1977

Effects of two anxiolytics on distraction, habituation and dishabitiuation.

Rats were engaged in a baseline activity of licking and their distraction to tone stimuli measured by an interruption in licking. Habituation, distraction to a stimulus change and dishabitiuation (the return of distraction to the original tone) were studied. Ethanol (0.4 and 0.8 g/kg) and chlordiazepoxide (7.5 mg/kg) produced significantly faster habituation, a result that cannot be attributed to changes in the baseline response rate, or to differences in the initial distraction to the tone. All groups showed 24 hr retention to the tone when they were tested in the same state in which they were habituated. There was transfer of habituation between drugged and undrugged states for rats injected with chlordiazepoxide, but rats habituated undrugged showed no retention if tested after injections of ethanol. Chlordiazepoxide impaired the specificity with which the physical parameters were coded, whereas ethanol improved the specificity of coding. Neither drug affected dishabituation.

Animals↗
PubMed1977

The effects of p-chlorophenylalanine and ethanolamine-O-sulphate in an animal test of anxiety.

p-Chlorophenylalanine, which produces a depletion of brain 5-HT concentration, had effects qualitatively similar to those previously found with chronic chlordiazepoxide and with acute ethanol in the social interaction test of anxiety. This result is compatible with the idea that a reduced turnover of 5-HT is important in anxiety reduction. On the same test, ethanolamine-O-sulphate, which raises brain gamma-aminobutyric acid, was without effect, suggesting raised concentrations of this acid are not essential for anxiety reduction.

Animals↗
PubMed1976

Acquisition and retention of habituation in the preweanling rat.

The acquisition and retention of habituation to air-puff was studied in rats on Days 1-19 postpartum. Animals of all ages demonstrated habituation but the rate of habituation varied with age: slower on each successive day from Day 1 to Day 8, but thereafter more rapid on each successive day. This peak of elicited responding is discussed in relation to the peak of spontaneous activity at Day 16 and to the pattern of neural development, including changes in acetylcholinesterase, norepinephrine, and serotonin, measured during the preweaning period. All ages showed 30-min retention of habituation, with 60-min retention developing after the 1st week. No evidence of 24-hr retention appeared at any age.

Acetylcholinesterase↗
PubMed1976

Are central cholinergic paths involved in habituation of exploration and distraction?

Experiment 1 tested the generality of Carlton's hypothesis that central muscarinic cholinergic pathways are involved in habituation of exploration. The effects of 3 muscarinic antagonists were tested in a holeboard, under 2 test conditions, i.e. with objects absent or present. Both the frequency and the duration of head-dipping were used as measures of exploration. Scopolamine prevented habituation only of the frequency of head-dipping, and only when objects were present. Atropine and benzhexol did not impair the habituation of either frequency of duration of head-dipping in either test condition. The impairment of habituation seemed therefore to be specific to scopolamine, and to the more complex test condition, and thus there was little to justify the suggestion that central cholinergic paths were generally involved. Experiment 2 investigated the effects of muscarinic antagonists on habituation of distraction. None of the drugs affected the distraction to tones, nor the subsequent habituation to these stimuli. Central cholinergic paths do not therefore seem to be involved in habituation of this behavioral response.

Acoustic Stimulation↗
PubMed1975

The reliability of the hole-board apparatus.

Two aspects of the reliability of the hole-board apparatus were investigated-the similarity between scores of different samples of the same population on their first exposure to the apparatus, and the test-retest reliability. Rats and mice were given a 5-min exposure to the hole-board and then retested for 5 min after 1, 2 or 8 days. Male rats and mice showed good initial exposure reliability, whereas the female mouse groups differed significantly. All animals showed a positive test-retest correlation (range 0.31-0.78), but a homogeneous group (e.g. all animals habituating) produced higher correlations (range 0.60-0.99). Comparison of scores on the two 5-min exposures showed that not all groups showed significant habituation, but the animals exposed to the hole-board for two 10-min periods showed both significant habituation and test-retest reliability.

Animals↗
PubMed1975

Validity of head-dipping as a measure of exploration in a modified hole-board.

To determine whether head-dipping could be validated as a measure of exploration a modified hole-board was developed with four holes in the floor, under which novel objects could be placed. Two criteria for considering head-dipping as a measure of exploration were proposed: firstly that it should reflect novel aspects of the environment; secondly, that exposure to the hole-board should result in information storage. That head-dipping reflected novelty was indicated by the longer duration of head-dips on initial exposure if objects were present, and also on a second exposure when objects were introduced for the first time. Information storage was indicated by habituation on re-exposure to the hole-board. A significant positive correlation between head-dipping in the "four" and "sixteen" hole-boards was obtained for rats, but not for mice. This provided some indirect evidence that rat head-dipping in the "sixteen hole-board" also reflects exploration. (+)Amphetamine and alcohol were tested in the modified hole-board, and (+)amphetamine decreased and alcohol increased the frequency and duration of head-dips.

Animals↗
PubMed1973

Effects of chlorpromazine on exploration and habituation in the rat.

1. The effects of chlorpromazine, 2 and 4 mg/kg, on exploration were investigated under two independent influences-food deprivation and time of day.2. Rats had three 3-minute trials in a hole-board apparatus; hole-investigation (head-dips) and general motor activity were recorded.3. On trial 1 chlorpromazine reduced exploration to half the control level, but on trial 3 it had no effect on motor activity or head-dips.4. General activity habituated from trial 1 to 3 in all groups, but some of the drug groups did not show significant habituation of head-dips, due to the low level of responding on trial 1.

Animals↗