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H D Kimmel

Publications and source records attributed to H D Kimmel.

At least 19 recordsLinked to original sources
PubMed1990

Persistent effects of a serotonin depletor (p-chlorophenylalanine) in regenerated planaria (Dugesia dorotocephala).

p-Chlorophenylalanine (pCPA) caused an increase in looping and locomotion speed in planaria (Dugesia dorotocephala). These effects dissipated quickly after treatment, except in animals that regenerated from worms surgically sectioned after treatment. Planaria that regenerated from head sections showed more looping 6 and 11 days later than tail regenerates, regenerates from untreated worms, and uncut worms. After the initial acceleration, pCPA animals, especially regenerates from tail sections, slowed down compared with untreated controls. Tail regenerates showed reduced speed 6 and 11 days later in comparison with head regenerates, regenerates from untreated animals, and uncut animals. The speed effect may have been due to pathogenesis in the eye spots in pCPA animals. The looping effect, however, may have been due to persisting serotonin depletion in the head regenerates. It is suggested that research on this problem might profitably be pursued with sexually reproducing planaria, to examine the possibility of genetic recoding due to serotonin depletion.

Animals↗
PubMed1989

[The effect of temporal distribution in relation to constant frequency of stimuli on habituation of the orienting reaction].

The lack of empirical evidence for faster habituation with the regular presentation of stimuli suggests that it is not the constancy of presentation of stimuli, but rather the rate of stimulation--defined as the reciprocal of the harmonic mean of the interstimulus intervals--that determines the speed of habituation. Using alternation of 10-70 and 30-50 sec and a constant sequence of 40 sec, three different rates of stimulation were realized. The hypothesis of faster habituation of skin conductance reactions with higher rates of stimulation was not confirmed. However, a consistent pattern of skin conductance reactions, with an increase in reaction after long intervals and a decrease after short intervals, was found, especially in the group with alternating intervals of 10 and 70 sec. The analysis of an additional group with a random sequence of intervals showed that the response pattern did not result simply from the expired time since last stimulus, i.e., a simple mechanical effect. The possibility of anticipating the stimuli and differing information content of the stimuli are discussed as possible determining factors.

Adult↗
PubMed1988

The Rescorla-Wagner theory does not predict contextual control of phasic responses in transswitching.

Theoretical predictions regarding differential phasic responding to the same phasic conditioned stimulus in two different tonic contexts, generated by a computer simulation of the Rescorla-Wagner theory of classical conditioning, were compared to empirical evidence of phasic switching in two studies of transswitching of the skin conductance response in humans. Significant phasic switching was found in both studies, but the Rescorla-Wagner theory substantially underestimated the obtained differences. It was shown that the theory predicts phasic differences that are more in accord with empirical data when the salience (alpha) of the contextual stimuli is assumed to be much greater than the salience (alpha) of the phasic conditioned stimulus. This modification in salience relationships, however, makes the Rescorla-Wagner theory more like Asratyan's theory of transswitching. Analysis of both tonic and phasic differentiation in experimental groups run with two different phasic stimuli AND two different tonic stimuli or with two phasic stimuli and only one tonic stimulus provided support for the conclusion that tonic response differentiation is a necessary precondition for obtaining phasic switching. It is suggested that the Rescorla-Wagner theory fails to account for phasic switching because it treats tonic and phasic stimuli as essentially equivalent, ignoring the fact that the tonic stimulus is present prior to the time that phasic stimuli occur and that responses to the tonic stimuli can occur during the period following tonic stimulus onset and preceding the administration of phasic stimuli.

Arousal↗
PubMed1986

The myth and the symbol of biofeedback.

This paper argues that biofeedback suffers from misrepresentation of its historical background and early development, false claims about its effects (e.g. mind-expansion) and that it now symbolizes political and social positions with which it has no connection. The myth that biofeedback arose as a revolutionary break from established science is shown to be false. The symbolization of biofeedback as antifascist and libertarian is also debunked. Unfair demands on biofeedback for miracle cures and excessive profiteering from the biofeedback technology are also criticized. It is urged that scientists and clinicians who know better about the real history and applicability of biofeedback should speak out whenever possible against these misrepresentations.

Biofeedback, Psychology↗
PubMed1977

Notes from "Pavlov's Wednesdays": sensory preconditioning.

Sensory preconditioning was first demonstrated in Pavlov's laboratory in 1931/32, rather than discovered by Brogden in 1939. Pavlov included nonassociative controls, forward pairing of the indifferent stimuli before reinforcing the second one with shock, and he avoided the development of inhibition to the compound by using a moving visual stimulus and a sound like that of scurrying mice, which both had persistent orienting reactions. Pavlov concluded that the indifferent stimuli were associated by temporal contiguity similar to human associations between successively spoken works. He did not consider the possibility of mediation via the orienting reactions.

Acoustic Stimulation↗
PubMed1976

Notes from "Pavlov's Wednesdays": Pavlov's law of effect.

Pavlov's Wednesday seminars indicate that he adopted homeostatic balance as a law of effect in order to deal with Konorski's experiments on omission and avoidance training; he did not, as is often thought, completely assimilate instrumental conditioning into his classical framework. He saw the 'new' type of conditioning as the basis of voluntary behavior in higher animals and devoted considerable attention to it in 1930-1933.

Animals↗
PubMed1976

Notes from "Pavlov's Wednesdays": Gestalt relationships as conditioned stimuli.

When A.O. Dolin's dog Ger was trained to differentiate between metronomic frequencies of 60 (positive) and 120 (negative) per minute, its conditioned salivary reaction to the positive stimulus was attenuated immediately after a test on a more positive stimulus (30 per minute) and that to the negative stimulus was augmented immediately after a test on a more negative stimulus (200 per minute). Pavlov and his colleagues considered explanations based on the relationship between the test and trained stimuli, on reciprocal induction, and on gradients of generalized excitation and inhibition à la Spence. This was just before Pavlov's death, but his last words on the topic leaned in the Gestalt relational direction.

Acoustic Stimulation↗
PubMedDate not supplied

Acquisition of a unique cue in positive and negative patterning?

Forty college students received a classical differential conditioning procedure involving both positive and negative patterning, each of these being associated with a different pair of stimuli. In positive patterning, elemental stimuli, A and B, were presented without an unconditioned stimulus while their compound, AB, was paired with electric shock. In negative patterning, elemental stimuli, C and D, were paired with shock while their compound, CD, remained unpaired. Thirty of these subjects then received a negative patterning transfer test on new stimuli, while ten subjects received a positive patterning transfer test. First interval response (FIR) and second interval response (SIR) were measured. During initial acquisition, positive patterning occurred in both dependent measures, but negative patterning was present only in the SIR. The transfer tests showed almost significant transfer of positive patterning in FIR and SIR. Negative patterning showed significant transfer neither in FIR nor SIR. It was concluded that, although elementary models of conditioning can explain positive patterning on the basis of summation of excitation from the elements to the compound, the occurrence of negative patterning in the SIR and the almost significant transfer of positive patterning in FIR and SIR appear to require the additional assumption of a unique cue.

Adult↗
PubMedDate not supplied

Blocking and unconditioned response diminution in human classical autonomic conditioning.

This paper summarizes the results of three experiments on blocking and unconditioned response diminution in human SCR conditioning. Recent theories of conditioning propose that reduced processing of the unconditioned stimulus due to conditioning results in reduced unconditioned response magnitude and in blocking of conditioning of a second conditioned stimulus when it is in compound with the previously conditioned stimulus. In these experiments, clear evidence of diminution of the unconditioned response was obtained in all three studies, but blocking was found only in the third study, which employed a within-subject design and in which the blocking was observed only after at least one extinction trial on both the blocked and nonblocked stimuli. Order of testing was not a factor in this delayed blocking effect. These results do not support the view that blocking occurs because of reduced processing of the unconditioned stimulus in the unconditioned response diminution sense.

Adult↗
PubMedDate not supplied

Extinction instead of incubation following classical aversive conditioning in dogs.

Two dogs received a single paired classical conditioning trial, with tone CS and 12 mA shock US. Both dogs then showed a conditioned blood pressure increase in response to the nonreinforced CS, which extinguished with additional nonreinforced presentations. The CR showed spontaneous recovery four days later, but reextinguished with additional nonreinforced presentations. The results were interpreted as not supporting Eysenck's theory of "incubation" following one-trial aversive conditioning.

Acoustic Stimulation↗
PubMedDate not supplied

Pavlovian conditional stimuli cannot always be defined solely in physical terms.

Twenty-four university students received differential Pavlovian conditioning with two colored stimuli separately accompanied by shock, and two other colored stimuli separately presented without shock. The reinforced and nonreinforced pairs of stimuli both contained complementary elements. After differentiation between the reinforced and nonreinforced elements was established, the complementary pairs were each additively mixed, (i.e., presented at the same time and in the same locus), producing two identical white compounds (established by pilot study). The subjects' skin-conductance responses to the two compounds showed that their different conditioning histories did not result in different responses. Rather, a simple declining function was obtained, resembling habituation or extinction. It was concluded that the definition of the conditional stimulus as a physical event is inappropriate in studies in which physically different stimuli may result in identical internal processes (or phenomenologic experiences)--for example, in additive color mixture.

Adult↗
PubMedDate not supplied

Operant GSR conditioning with cool air reinforcement.

Two groups of 20 Ss each run individually in a soundproff chamber heated to 115 F and humidified to 100%. Ss in the experimental group received brief presentation of cool air contingent upon wmitted GSRs during 20 min of acquisition. Control Ss were matched on at a time in operant rate and were yoked one at a time to receive the cool air on a response-independent schedule. Both groups increased significantly in rate of unelicited GSRs during acquisition, with the experimental Ss' curve rising more rapidly and both groups attaining equivalent terminal levels. During extinction, the groups maintained high levels of responding and did not differ. Examination of basal skin conductance data ruled our an activation hypothesis. In the control Ss, terminal response frequency was significantly correlated with percentage of fortuitous response-contigent reinforcement. It was concluded that both croups were conditioned, with the controls receiving intermittent reinforcement sufficiently often to elevate their responding. The cool air was judged to be an effective reinforcer of unelicited GSRs, perhaps more effective than those used in previous studies.

Air↗
PubMedDate not supplied

Autonomic concomitants of discriminative avoidance and punishment training in the monkey.

Two Cebus albifrons monkeys were trained to press a back-lighted panel to postpone a brief electric shock to the tail using a Sidman avoidance schedule (SS = 40 sec, RS = 40 sec). After 25 training sessions, a discriminative schedule was introduced, with the Sidman avoidance continuing in the presence of one discriminative stimulus and punishment introduced in the presence of the other. The discriminative stimuli were colors on the panel. Discriminative training also involved 25 sessions, each with a random sequence of 6 avoidance and 6 punishment segments, with 30 sec intervals between the segments. Plantar skin conductance and heart rate were recorded along with the panel-pressing behavior. The two monkeys adjusted to the discriminative schedule quite differently from one another. One animal responded at a high level and avoided very well (during avoidance) but was punished frequently (during punishment). The other animal responded less frequently and received many shocks during avoidance but almost none during punishment. The animal that showed less ability to inhibit responding (and received about four times as many shocks overall) appeared to have discriminated better temporally in spacing its responses during avoidance training. The monkey whose panel-pressing behavior resulted in more shocks also tended to show a higher tonic level of autonomic arousal. However, within-animal differences in shock frequency (between avoidance and punishment) were not similarly related to autonomic arousal. The animal that received fewer shocks overall (but more during avoidance) showed greater arousal during punishment. The animal that received more shocks overall (but fewer during avoidance) showed no arousal differences between avoidance and punishment.

Animals↗
PubMedDate not supplied

Extending the Rescorla-Wagner theory to account for transswitching.

This article is a brief response to commentaries made by Bond and Siddle (1988) and Lovibond (1988) to our article (Kimmel & Lachnit, 1988) outlining some of the difficulties encountered by the Rescorla-Wagner theory in predicting the outcome of transswitching experiments. We show that Bond and Siddle's assertion that increasing the value of beta would "bring the model into line with the empirical data" (p. 186) is incorrect. Increasing beta in simulated transswitching experiments causes the theory to predict a more rapid increase in associative values, to higher levels, but does not change the degree of predicted phasic switching. We agree with Lovibond's observation that the Rescorla-Wagner theory can predict phasic switching more effectively if it is assumed that an unobserved additional stimulus is present whenever the phasic stimulus occurs in positive tonic segments and a different unobserved additional stimulus is present whenever the phasic stimulus occurs in negative tonic segments. But this kind of usage of the "unique cue hypothesis" does little more then immunize a theory against problematic empirical findings. When the salience of the unique cue is increased relative to that of the stimuli that are actually physically present, simulated transswitching experiments show greater and greater phasic switching. But, unless there is a good a priori reason to postulate such unique cues, or unless the unique cue hypothesis leads to empirically testable new hypotheses, it does not provide a scientifically useful solution to the theory's problem with transswitching.

Association Learning↗