John W. Hennessy’s research while affiliated with University of Illinois at Chicago and other places

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Publications (4)


Learning Theory: Two Trials and Tribulations
  • Article
  • Publisher preview available

March 1974

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7 Reads

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6 Citations

American Psychologist

P. E. Freedman

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John Hennessy

Conducted a series of experiments to demonstrate that organisms tend not to repeat a response after reinforcement is "consumed," contrary to the basic tenet of learning theory. Using varied combinations of Ss, including college sophomores, nurses, children, and "real people," and varying apparatus from a black box to paper cups, the hypothesis was confirmed. Additional hypotheses were developed relating to naivete, expectancies of deception, and elaborate instrumentation. (PsycINFO Database Record (c) 2012 APA, all rights reserved)

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Effects of varying active/passive shock levels in shuttlebox avoidance in rats

January 1974

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12 Reads

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14 Citations

Journal of Comparative and Physiological Psychology

Ran 60 male Sprague-Dawley albino rats in a shuttle box with 3 levels of shock intensity-high (H), medium (M), and low (L)-which varied independently on each side. This yielded 6 groups defined by the shock level in the 2 chambers: H-H, M-M, L-L, H-L, H-M, M-L. Results indicate that when active shock level was held constant, avoidance behavior was a function of passive shock level, with lower passive shock level producing higher levels of avoidance. Avoidance was not a function of active shock level when passive shock level was held constant. 10 controls were run using a unidirectional paradigm, and avoidance was not found to be a function of the active shock level. Results are interpreted as emphasizing the role of passive avoidance in bidirectional shuttling. (PsycINFO Database Record (c) 2012 APA, all rights reserved)


Adrenocortical influences upon the extinction of an appetitive runway response

January 1974

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6 Reads

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23 Citations

Physiology & Behavior

Sprague-Dawley rats received daily injections of either ACTH, hydrocortisone, corticosterone, or placebo throughout the acquisition and extinction of a food-reinforced runway response. The results showed that hormone injections produced no systematic effects upon acquisition performance. Injections of either hydrocortisone or corticosterone, however, produced faster running on early extinction trials as compared to either ACTH or placebo injection. There was some suggestion that increased corticosteroid levels, rather than some change in ACTH levels, produced the effects upon extinction responding.


The effects of post reinforcement delay and early sucrose experience on sucrose incentive shift performance in the rat

January 1973

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4 Reads

Japanese Psychological Research

Two experiments were performed which investigated the roles of goal box experience and sucrose novelty on sucrose-incentive-shift performance.It was hypothesized that both post-reinforcement delay and early sucrose experience would lead to rapid response decrements following an incentive reduction. Neither of these hypotheses were supported and further research is needed to elucidate the mechanism involved in the slow behavioral adjustments to decreased sucrose rewards. © 1973, The Japanese Psychological Association. All rights reserved.

Citations (2)


... These negative results may not be attributed to rupture of the tympanic membrane during stereotaxic surgery or the tone parameters used in this study. Supporting this statement, an independent group of animals submitted to the same procedure, except for the pairing of tone with footshock, showed reliable learning rates comparable to those from typical avoidance-escape procedures that utilize an auditory stimulus paired with electric shock as the unconditioned stimulus (21,22). One possible explanation for these surprising results is that repeated electrical stimulation of Light + brain stimulation Tone + brain stimulation Tone + footshocks * * 1st 2nd Figure 3 -Number of avoidance responses during the first and second segments of two-way active avoidance sessions for rats submitted to conditioning by pairing light or a tone with brain stimulation and a tone with footshock. ...

Reference:

Signaled two-way avoidance learning using electrical stimulation of the inferior colliculus as negative reinforcement: Effects of visual and auditory cues as warning stimuli
Effects of varying active/passive shock levels in shuttlebox avoidance in rats

Journal of Comparative and Physiological Psychology

... The influence of the pituitary-adreno-cortical axis was examined with adrenocorticotropin hormone (ACTH), corticosterone, or cortisol injections throughout testing, with the result that only the latter two hormones delayed extinction while none affected acquisition [110]. Different results were found in another study when ACTH injections throughout testing facilitated extinction while slowing down acquisition speeds [36] but retarded extinction when administered only during extinction [111]. ...

Adrenocortical influences upon the extinction of an appetitive runway response
  • Citing Article
  • January 1974

Physiology & Behavior