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R M Gilbert

Publications and source records attributed to R M Gilbert.

31 records · Page 2Linked to original sources

Ubiquity of schedule-induced polydipsia.

Spaced feeding of individual food pellets to food-deprived rats induced excessive drinking after pellet delivery if water was continuously available. When access to water was restricted to a portion of the inter-pellet interval, and competition from food-reinforced bar pressing was removed, excessive drinking occurred whenever drinking was possible. This finding extends the generality of accounts of excessive behavior that implicate induction by apparently unrelated scheduling characteristics of the environment.

Animals↗

Signal functions in discriminated avoidance behavior.

Four rats were trained to lever press under a discriminated avoidance/escape schedule in which separately signalled safe and warning periods were 100 sec and 32 sec respectively. The auditory and not the visual component of the compound warning signal became associated with the discriminative control of lever pressing. Avoidance behavior also came under temporal control, in that the probability of lever pressing increased as the warning period progressed. Timing began with the onset of the warning signal rather than the offset of the safe signal. However, after the warning signal had been progressively eliminated, timing began with the offset of the safe signal. When neither signal was normally available, the temporal distribution of avoidance behavior changed markedly. Drifts in the temporal distribution of lever pressing occurred throughout the study; these were manipulated for two animals.

Animals↗

High-frequency hearing losses caused by low-frequency noises.

Human subjects were exposed to an octave-band noise for 24 hours. Temporary threshold shifts increased for the first eight hours of exposure and then were asymptotic. While threshold shifts were largest at about one-half octave above the center frequency of the noise, a second maximum was observed at higher test frequencies. The exact frequency of this second maximum decreased from 7.0 kHz, for a noise centered at 2.0 kHz, to 5.5 kHz for a noise centered at 0.5 kHz. This result could be caused by the travelling wave pattern along the cochlear partition or to the production of distortion products.

Auditory Threshold↗