Classical conditioning: The new hegemony

HYPNOTIC RESPONSIVENESS AND NONHYPNOTIC SUGGESTIBILITY: DISPARATE, SIMILAR, OR THE SAME?

This study examined if participants respond to different types of suggestions, including hypnosis, uniquely or similarly. This study used 9 suggestibility measures and hypothesized a 3-factor model. It was hypothesized that hypnosis, Chevreul's pendulum, and body-sway would load on the first factor; the odor test, progressive weights, and placebo on the second factor; and conformity, persuasibility, and interrogative suggestibility would load on the third factor. The study comprised 110 college students. Factor analyses failed to result in three factors. Additional attempts at two and three-factor models were also rejected. Hypnosis had no strong relationship with the various suggestibility measures. Thus, no clearly delineated factor structure of suggestibility emerged, indicating that the domain of suggestibility seems to be neither a single attribute, trait, or group of related abilities. Implications are discussed.

Stimulus-associated urinary urges in overactive bladder syndrome

AIMS

Although anecdotal reports of urinary urgency at one's front door are common in overactive bladder syndrome (OAB), little research has been done on how one's front door and other stimuli are related to urinary symptoms. We hypothesized that individuals with OAB would have higher scores on the Urinary Cues Questionnaire, developed for this study to assess stimulus-associated urinary urges, than those without OAB.

METHODS

Online surveys were administered to 328 women age 18-40 years recruited from a respondent panel maintained by CINT such that one-third of the sample reported a diagnosis of OAB. The survey assessed OAB symptoms and the frequency with which participants associated 42 stimuli with the urge to urinate.

RESULTS

Psychometric analyses showed internal consistency estimates of the Urinary Cues Questionnaire of α = 0.97 and a test-retest correlation of 0.91. Women with OAB had significantly higher Urinary Cues Scores than those without OAB, with a t-test showing a large effect size of d = 1.49 (95%CI 1.24, 1.74), P < 0.001.

DISCUSSION

Behavioral treatments aimed at reducing the response to cues may be useful in OAB, but more research is needed on both treatment implications and on the trajectory of symptom development.

The Adaptive Significance of Sexual Conditioning: Pavlovian Control of Sperm Release

Male quail received Pavlovian conditioning trials that consisted of placement in a distinctive experimental chamber (the conditioned stimulus) paired with the opportunity to copulate with a female (the unconditioned stimulus). For control subjects, exposures to the conditioned and unconditioned stimuli were unpaired. After four and six trials, each subject was placed in the experimental chamber with a probe stimulus that included some of the visual cues of a female's head and neck. Pavlovian conditioning increased how much time subjects spent near the probe stimulus. Conditioned subjects also released greater volumes of semen and greater numbers of spermatozoa than the control subjects. Significant differences were not obtained in serum testosterone levels or in other measures of sperm quality. These results demonstrate that sexual Pavlovian conditioning can affect reflexes involved in sperm release and thereby modulate reproductive fitness.

The role of conditioning, learning and dopamine in sexual behavior: a narrative review of animal and human studies

Many theories of human sexual behavior assume that sexual stimuli obtain arousing properties through associative learning processes. It is widely accepted that classical conditioning contributes to the etiology of both normal and maladaptive human behaviors. Despite the hypothesized importance of basic learning processes in sexual behavior, research on classical conditioning of the sexual response in humans is scarce. In the present paper, animal studies and studies in humans on the role of pavlovian conditioning on sexual responses are reviewed. Animal research shows robust, direct effects of conditioning processes on partner- and place preference. On the contrast, the empirical research with humans in this area is limited and earlier studies within this field are plagued by methodological confounds. Although recent experimental demonstrations of human sexual conditioning are neither numerous nor robust, sexual arousal showed to be conditionable in both men and women. The present paper serves to highlight the major empirical findings and to renew the insight in how stimuli can acquire sexually arousing value. Hereby also related neurobiological processes in reward learning are discussed. Finally, the connections between animal and human research on the conditionability of sexual responses are discussed, and suggestions for future directions in human research are given.

From an animal's point of view: Motivation, fitness, and animal welfare

To study animal welfare empirically we need an objective basis for deciding when an animal is suffering. Suffering includes a wide range ofunpleasant emotional states such as fear, boredom, pain, and hunger. Suffering has evolved as a mechanism for avoiding sources ofdanger and threats to fitness. Captive animals often suffer in situations in which they are prevented from doing something that they are highly motivated to do. The “price” an animal is prepared to pay to attain or to escape a situation is an index ofhow the animal “feels” about that situation. Withholding conditions or commodities for which an animal shows “inelastic demand” (i.e., for which it continues to work despite increasing costs) is very likely to cause suffering. In designing environments for animals in zoos, farms, and laboratories, priority should be given to features for which animals show inelastic demand. The care ofanimals can thereby be based on an objective, animal-centered assessment of their needs.

On Strong Anticipation

We examine Dubois's (2003) distinction between weak anticipation and strong anticipation. Anticipation is weak if it arises from a model of the system via internal simulations. Anticipation is strong if it arises from the system itself via lawful regularities embedded in the system's ordinary mode of functioning. The assumption of weak anticipation dominates cognitive science and neuroscience and in particular the study of perception and action. The assumption of strong anticipation, however, seems to be required by anticipation's ubiquity. It is, for example, characteristic of homeostatic processes at the level of the organism, organs, and cells. We develop the formal distinction between strong and weak anticipation by elaboration of anticipating synchronization, a phenomenon arising from time delays in appropriately coupled dynamical systems. The elaboration is conducted in respect to (a) strictly physical systems, (b) the defining features of circadian rhythms, often viewed as paradigmatic of biological behavior based in internal models, (c) Pavlovian learning, and (d) forward models in motor control. We identify the common thread of strongly anticipatory systems and argue for its significance in furthering understanding of notions such as "internal", "model" and "prediction".

"Maybe I made up the whole thing": placebos and patients' experiences in a randomized controlled trial

Patients in the placebo arms of randomized controlled trials (RCT) often experience positive changes from baseline. While multiple theories concerning such "placebo effects" exist, peculiarly, none has been informed by actual interviews of patients undergoing placebo treatment. Here, we report on a qualitative study (n = 27) embedded within a RCT (n = 262) in patients with irritable bowel syndrome. Besides identical placebo acupuncture treatment in the RCT, the qualitative study patients also received an additional set of interviews at the beginning, midpoint, and end of the trial. Interviews of the 12 qualitative subjects who underwent and completed placebo treatment were transcribed. We found that patients (1) were persistently concerned with whether they were receiving placebo or genuine treatment; (2) almost never endorsed "expectation" of improvement but spoke of "hope" instead and frequently reported despair; (3) almost all reported improvement ranging from dramatic psychosocial changes to unambiguous, progressive symptom improvement to tentative impressions of benefit; and (4) often worried whether their improvement was due to normal fluctuations or placebo effects. The placebo treatment was a problematic perturbation that provided an opportunity to reconstruct the experiences of the fluctuations of their illness and how it disrupted their everyday life. Immersion in this RCT was a co-mingling of enactment, embodiment and interpretation involving ritual performance and evocative symbols, shifts in bodily sensations, symptoms, mood, daily life behaviors, and social interactions, all accompanied by self-scrutiny and re-appraisal. The placebo effect involved a spectrum of factors and any single theory of placebo--e.g. expectancy, hope, conditioning, anxiety reduction, report bias, symbolic work, narrative and embodiment--provides an inadequate model to explain its salubrious benefits.

Classical Conditioning: Still Going Strong

This paper summarizes developments in the field of classical conditioning. Attention is paid to four common misconceptions of what is classical conditioning. First, classical conditioning does not ensue as a simple result of temporal pairing of conditioned and unconditioned stimuli. Rather, conditioned reacting occurs if and to the degree that the subject is able to predict the occurrence of one stimulus from the presence of another one. Second, what is learned during classical conditioning is not necessarily a response to a cue, but rather a probabilistic relationship between various stimuli. Third, classical conditioning is not only manifested in responses mediated by the autonomic nervous system, but also in immunological parameters, in motoric behaviour and in evaluative judgments. Fourth, the nature of the conditioned and the unconditioned stimulus is (often) not a matter of indifference: particular combinations of CS and US produce more powerful conditioning effects than do other combinations. In the second part of the paper, the potential relevance of these developments is illustrated. Discussions are included about anxiety, addictions and food aversions/conditioned nausea.

Learning effects on sperm competition and reproductive fitness

Learning and other common psychological processes presumably evolved because they contribute to reproductive fitness, but reproductive outcomes are rarely measured in psychology experiments. We examined the effects of Pavlovian conditioning on reproductive fitness in a sperm-competition situation. Typically, two males mating with the same female in immediate succession sire similar numbers of offspring. In a study with domesticated quail (Coturnix japonica), we increased paternity success by presenting a Pavlovian signal that permitted one of two competing males to predict copulatory opportunity. Using microsatellite-based DNA fingerprinting, we found that signaled males sired 72% of the offspring when competing with control males, and this effect was independent of copulation order. In the absence of Pavlovian conditioning, rates of fertilization were not significantly different for two males that copulated with the same female. These findings demonstrate that Pavlovian conditioning contributes to reproductive fitness and suggest that individual past experience can bias genetic transmission and the evolutionary changes that result from sexual competition.

Function transformation without reinforcement

In studies of function transformation, participants initially are taught to match stimuli in the presence of a contextual cue, X; the stimuli to be matched bear some formal relation to each other, for example, a relation of opposition or difference. In a second phase, the participants are taught to match arbitrary stimuli (say, A and B) in the presence of X. In a final test, A often displays behavioral functions that differ from those of B, and can be predicted from the nature of the relation associated with X in the initial training phase. Here we report function-transformation effects in the absence of selection responses and of their reinforcers. In three experiments with college students, exposure to relations of difference or identity modified the responses given to later stimuli. In Experiment 1, responses to a test stimulus A varied depending on preexposure to pairs of colors that were distinct from A but exemplified relations of difference or identity. In Experiment 2, a stimulus A acquired distinct functions, depending on its previous pairing with a contextual cue X that had itself been paired with identity or difference among colors. Experiment 3 confirmed the results of Experiment 2 with a modified design. Our data are consistent with the notion that relations of identity or difference can serve as stimuli for Pavlovian processes, and, in compound with other cues, produce apparent function-transformation effects.

Slowly forgetting the Pavlovian adventure?

This paper analyses an interesting story, that of the physiologist Ivan Petrovitch Pavlov. While investigating the causes of salivary secretions in the waking, behaving dog, he discovered a class of causes that he called psychic, since they were associated with perceiving a visual, acoustic or other signal, delivered before food that normally created salivation. A temporary relationship was therefore established, between the secretory command and the cerebral site associated with an initially neutral stimulus that had become a signal. This gave rise to the "conditional reflex". Pavlov was probably not the first who had observed this kind of association, but he very skillfully exploited these data to create a coherent conceptual system. In 23 "lectures", he very precisely summarized his views and retraced the fundamental issues explaining the main features of the purely physiological cerebral command of behaviour. The Pavlovian system necessarily became, in the particular environment of the soviet regime, a kind of credo on physical-mental relationships based upon a generalized reflexology, not allowing any deviation, nor any dissidence, nor any concession to subjectivity. The notion of conditional reflex has indeed resisted to time, but number of subtleties of the Pavlovian thinking and many phenomena that he described now seem forgotten and to have lost much of their heuristic value. Most of the recent theories of learning have only rarely followed Pavlov's line, to concentrate on more complex learning modalities.

Differential conditioning of alpha amplitude: A fresh look at an old phenomenon

OBJECTIVE

To determine the latency and development of conditional suppression of alpha amplitude and its relationship to behaviour, alpha amplitude (8-13 Hz) was measured in a differential conditioning procedure.

METHODS

The CS+/- were tones and the US was a photic checkerboard. Alpha amplitude, CNV, RT and verbal responses were recorded from 12 participants.

RESULTS

The CS+/- difference in acquisition was greatest from 250 ms before the US. It was greatest from the trial where RT declined and participants could report the CS+/US relationship. There was an amplitude increase in lower band activity 230 ms after the US. This looked like a VEP but was produced by phase-locked activity starting before the US.

CONCLUSIONS

Predicting the US led to cortical priming. Amplitude change in acquisition is congruent with CNV, RT and verbal performance.

SIGNIFICANCE

Prediction, expectancy and motor preparation are reflected in changes in alpha activity. These results provide converging evidence for the functional role of 8-10 Hz activity. They complement the emerging picture of the role of alpha activity in cognition, indicating that it extends to the acquisition of predictive knowledge.

Pavlovian Conditioning: A Functional Perspective

From a functional perspective, Pavlovian conditioning involves learning about conditioned stimuli (CSs) that have a pre-existing relation to an unconditioned stimulus (US) rather than learning about arbitrary or neutral CSs. In addition, the most important product of learning involves changes in how the organism responds to the US, not in how it responds to the CS, because the US is the more biologically relevant stimulus. These concepts are illustrated using examples from a variety of behavioral and physiological situations including caloric intake and digestion, breast feeding, poison-avoidance learning, eyeblink conditioning, sexual conditioning, fear conditioning, aggression, and drug tolerance and sensitization.

Function transfer in human operant experiments: the role of stimulus pairings

Although function transfer often has been studied in complex operant procedures (such as matching to sample), whether operant reinforcement actually produces function transfer in such settings has not been established. The present experiments, with high school students as subjects, suggest that stimulus pairings can promote function transfer in conditions that closely approximate those of matching to sample. In Experiment 1, the subjects showed transfer of operant responding from three geometric figures (C1, C2, C3) to three colored shapes (B1, B2, B3) when the latter were paired with the former. Experiment 2 involved two groups of subjects. In the matching group, subjects matched the colored shapes with the geometric figures; in the yoked group, the shapes were merely paired with the geometric figures, and the schedule of stimulus pairing was yoked to the performance of the subjects in the matching group. Both groups of subjects showed function transfer. Experiment 3 documented function transfer from C stimuli to B stimuli through indirect stimulus pairings (A-B, A-C). In Experiment 4, function transfer was obtained even though the subjects vocalized continuously during the pairing trials, presumably preventing covert verbalization that might mediate transfer effects. Our results are consistent with a Pavlovian account and raise difficulties for current operant theories of function transfer.

Roots of the Pavlovian Society's missions of the past and present: the Pavlov dimension

This paper offers an interpretation of the relation between Pavlov's life and work and the missions of the Pavlovian Society, both past ("observation and observation") and present ("interdisciplinary research on the integrated organism"). I begin with an account of Pavlov's life and his influence on contemporary thought. I then indicate the relation of some of Pavlov's attitudes (e.g., his motto, his epistemological stance) to the Society's past mission. In the concluding and most controversial section, I argue for six guiding principles derived from Pavlov, to be applied to the Society's mission. These are: (a) a confident methodological behaviorism; (b) a significant role assigned to both physiological and psychological factors in the prediction and control of the integrated organism; (c) approximately equal taxonomic precision of physiological and psychological explanatory concepts; (d) distrust of teleological explanatory concepts; (e) rejection of psychology's instrumentalist "cognitive paradigm shift"; and (f) rejection of the representational theory of knowledge.

The contribution of suggestibility and expectation to placebo analgesia phenomenon in an experimental setting

This study reports how placebo analgesia was produced by conditioning whereby the intensity of electric stimulation was surreptitiously reduced in order to examine the contribution of psychological factors of suggestibility and expectancy on placebo analgesia. This strategy was used in order to manipulate expectancy for pain reduction. The magnitudes of the placebo effects were estimated after a manipulation procedure and during experimental trials in which stimulus intensities were reset to original baseline levels. Individual differences in suggestibility, verbal expectancy for drug efficacy and manipulation procedure for pain reduction were tested as possible mediators of placebo analgesia. The following dependent variables were measured: (a) subjective expectancy for drug efficacy in pain relief, (b) expected pain intensity and unpleasantness, (c) concurrent pain intensity and unpleasantness and (d) remembered pain intensity and unpleasantness. Statistically significant placebo effects on sensory and affective measures of pain were obtained independently of the extent of the surreptitious lowering of stimulus strength during manipulation trials. The pairing of placebo administration with painful stimulation was sufficient to produce a generalized placebo analgesic effect. However, verbal expectancy for drug efficacy and individual differences in suggestibility were found to contribute significantly to the magnitude of placebo analgesia. The highest placebo effect was shown by the most pronounced reductions in pain ratings in highly suggestible subjects who received suggestions presumed to elicit high expectancy for drug efficacy. The results also demonstrated that placebo effects established on remembered pain were at least twice as great as those obtained on concurrent placebo effects. This was mainly because baseline pain was remembered as being much more intense than it really was. Moreover, remembered placebo effects, like the concurrent placebo effects, were highly correlated with expected pain scores obtained just after manipulation trials. These results indicate that multiple factors contribute to the placebo effect, including suggestibility, expectancy and conditioning, and that the judgement of placebo analgesia is critically determined by whether pain relief is assessed concurrently or after treatment.

Patients' pretreatment expectations of chemotherapy-related nausea are an independent predictor of anticipatory nausea

Based on extensive research with animals, classical conditioning theorists have come to regard contingency as the primary factor in the development of conditioned responses. However, recent experimental work with humans has suggested the possibility that participant expectations may also directly contribute to the development of conditioned responses. To date, this phenomenon has not been investigated in clinical settings. Anticipatory nausea (AN) in chemotherapy patients, widely viewed as the best established example of classical conditioning in clinical medicine, provides an opportunity to examine the contributions of patient expectations to the development of a conditioned response outside the laboratory. The present study of 59 breast cancer patients supported the hypothesis that pretreatment patient expectations make a significant (p < .03) contribution to the development of AN after statistically controlling for the strongest conditioning predictor, contingency. These data imply that patient expectations should be considered when evaluating conditioned responses to aversive medical treatments.

Separate Effects of a Classical Conditioning Procedure on Respiratory Pumping, Swimming, and Inking in Aplysia fasciata

We examined whether swimming and inking, two defensive responses in Aplysia fasciata, are facilitated by a classical conditioning procedure that has been shown to facilitate a third defensive response, respiratory pumping. Training consisted of pairing a head shock (UCS) with a modified seawater (85%, 120%, or pH 7.0 seawater—CSs). Animals were tested by re-exposing them to the same altered seawater 1 hr after the training. For all three altered seawaters, only respiratory pumping is specifically increased by conditioning. Swimming is sensitized by shock, and inking is unaffected by training, indicating that the conditioning procedure is likely to affect a neural site that differentially controls respiratory pumping. Additional observations also indicate that the three defensive responses are differentially regulated. First, different noxious stimuli preferentially elicit different defensive responses. Second, the three defensive responses are differentially affected by shock. Inking is elicited only immediately following shock, whereas swimming and respiratory pumping are facilitated for a period of time following the shock. Third, swimming and respiratory pumping are differentially affected by noxious stimuli that are delivered in open versus closed environments. These data confirm that neural pathways exist that allowAplysia to modulate separately each of the three defensive behaviors that were examined.

Ubiquitous molecular substrates for associative learning and activity-dependent neuronal facilitation

Recent evidence suggests that many of the molecular cascades and substrates that contribute to learning-related forms of neuronal plasticity may be conserved across ostensibly disparate model systems. Notably, the facilitation of neuronal excitability and synaptic transmission that contribute to associative learning in Aplysia and Hermissenda, as well as associative LTP in hippocampal CA1 cells, all require (or are enhanced by) the convergence of a transient elevation in intracellular Ca2+ with transmitter binding to metabotropic cell-surface receptors. This temporal convergence of Ca2+ and G-protein-stimulated second-messenger cascades synergistically stimulates several classes of serine/threonine protein kinases, which in turn modulate receptor function or cell excitability through the phosphorylation of ion channels. We present a summary of the biophysical and molecular constituents of neuronal and synaptic facilitation in each of these three model systems. Although specific components of the underlying molecular cascades differ across these three systems, fundamental aspects of these cascades are widely conserved, leading to the conclusion that the conceptual semblance of these superficially disparate systems is far greater than is generally acknowledged. We suggest that the elucidation of mechanistic similarities between different systems will ultimately fulfill the goal of the model systems approach, that is, the description of critical and ubiquitous features of neuronal and synaptic events that contribute to memory induction.

Introduction and commentary to: M.I. Mityushov (1954) "Conditioned reflex secretion of insulin"

Recent research on the role of classical conditioning in homeostatic regulation (Dworkin, 1993; Siegel, Krank & Hinson, 1987) has underscored the potential importance of the work of earlier Eastern-European work on physiological conditioning. The present article is a translation and discussion of a paper on blood glucose conditioning, first published in 1954 by the Russian physiologist M.I. Mityushov. Mityushov was able to demonstrate conditioned hypoglycemia in humans and dogs after using an injection procedure as the CS and intravenous glucose as the UCS. The translation is preceded by a general introduction and followed by a reanalysis and discussion of Mityushov's results.