Increasing implicit self-esteem through classical conditioning

Implicit self-esteem is the automatic, nonconscious aspect of self-esteem. This study demonstrated that implicit self-esteem can be increased using a computer game that repeatedly pairs self-relevant information with smiling faces. These findings, which are consistent with principles of classical conditioning, establish the associative and interpersonal nature of implicit self-esteem and demonstrate the potential benefit of applying basic learning principles in this domain.     

Human classical conditioning

Recent reports of failure to obtain blocking in human galvanic skin response (GSR) conditioning, together with our own equivocal results with eyelid conditioning, have motivated us to re-examine the status of the conditioned stimulus (CS) in human conditioning studies. The issues raised by compound stimuli, by contextual cues and occasion setting stimuli, and by cross-modal transfer are considered in the light of data from our laboratories. These data include observations on the interchangeability of stimulus modalities during acquisition, the use of varying information loads embedded in occasion setting displays, the comparison of alternative blocking designs and the analysis of response topography in relation to stimulus variability. They suggested that an adequate account of the CS in human conditioning studies must recognize that it is dynamically processed and reprocessed both during and after acquisition.     

Implicit attitude generalization occurs immediately; explicit attitude generalization takes time

People are able to explicitly resist using knowledge about one person to evaluate another person from the same group. After learning about positive and negative behaviors performed by one individual from each of two different groups, participants were introduced briefly to new individuals from the groups. Implicit evaluations of the original individuals readily generalized to the new individuals; explicitly, participants resisted such generalization. Days later, both implicit and explicit evaluations of the original individuals generalized to the new individuals. The results suggest that associative links (e.g., shared group membership) are sufficient for implicit attitude generalization, but deliberative logic (e.g., individual group members are not necessarily the same) can reduce explicit generalization by association. When knowledge distinguishing who did what is unavailable, such as after forgetting, associative knowledge provides the basis of explicit evaluation. We conclude that a simple association linking one individual to another can produce implicit attitude generalization immediately and explicit attitude generalization eventually.     

A comparison of the effects of vicariously instigated classical conditioning and direct classical conditioning procedures

Two groups of Ss received either two or 16 paired classical conditioning trials beyond the peak CR. A third group received the same stimuli as in the 16 postpeak condition but in an unpaired and random order. The stimuli in all three groups were delivered directly to S. Subsequently, all three groups, including a fourth which was not given any prior direct classical conditioning, were exposed to vicariously instigated classical conditioning. This consisted of havingS observe someone (model) employed byE who received the same CS as was delivered during direct conditioning. The CS was paired with the feigned arm movement of the model, simulating a reaction to shock. This vicarious classical conditioning procedure when compared to direct classical conditioning resulted in smaller GSR magnitudes for both the CRs and UCRs. Previous experience with direct classical conditioning seems to have had an attenuating effect on GSR magnitude during the vicarious situation. A postexperimental questionnaire tended to support the results, and the relationship between the present study and current classical conditioning theory is discussed.     

A neutral odor may become a sexual incentive through classical conditioning in male rats

A neutral olfactory stimulus was employed as CS in a series of experiments with a sexually receptive female as UCS and the execution of an intromission as the UCR. Each experimental session lasted until the male ejaculated. The time the experimental subject spent in a zone adjacent to the source of the olfactory stimulus during the 10 s of CS presentation and the latency to enter that area were employed as measures of conditioning. In Experiment 1, the CS was always presented at the same location in the conditioning arena, bordering the site where the female became accessible. Conditioning resulted in a gradual increase in the time spent in the CS zone as well as in a reduction of the latency to enter it. In Experiment 2, the site of presentation of the CS was varied randomly from one side of the conditioning arena to another in order to assure that the subjects indeed associated the CS and not a particular location with access to a female. Again, the time spent in the CS zone increased and the latency to enter it was reduced by conditioning. Furthermore, after conditioning the CS was approached more than a neutral odor in a different context. In a third experiment one group of animals was randomly exposed to the CS to control for non-associative effects on performance. Another group was conditioned as in Experiment 2. The random presentation of the CS failed to enhance approach, while the paired UCS-CS had effects identical to those found in Experiment 2. In the last experiment, an olfactory CS⁻ was included. The CS⁺ and CS⁻ were presented in random order at random locations. Both the time spent in the CS⁺ and CS⁻ zones was increased, while the latency to enter the zone was significantly reduced only for the CS⁺. These data suggest that the subjects had partially learned to discriminate between the CS⁺ and the CS⁻, at most. The procedure employed in Experiments 2 and 3 seems to be the most promising for studies of sexual conditioning in male rats.     

The prefrontal-thalamic axis and classical conditioning

Using the New Zealand albino rabbit as an animal model, it has been determined that the medial prefrontal cortex is intimately involved in, and may be necessary for, acquisition of classically conditioned bradycardia. The interconnected nuclei of the medial thalamus, most notably the mediodorsal nucleus, conversely appear to be associated with the development of the tachycardia that accompanies classical conditioning of the eyeblink and nictitating membrane response. Neuroanatomical, electrophysiological, brain stimulation, and lesion data are reviewed, which support the conclusion that the prefrontal-thalamic axis is intimately involved in acquisition of classically conditioned visceral changes.     

Comparison of timing and classical conditioning

Four experiments with rats investigated if the timing of a stimulus (sound) correlated with the strength of a conditioned response (CR) to the stimulus. The timing (effective duration) of the stimulus was measured using the peak procedure, similar to a discrete-trials fixed-interval procedure. The rats were trained so that their response rate reached a maximum about 40 s or 60 s after the onset of a light; the time of the maximum measured from the start of the light (peak time) was the measure of timing. On some trials, the light was preceded by a short (5 s) or long (20 s or 30 s) interval of sound. We assumed that the difference in peak time after long and short sounds reflected the timing of the sound--if the sound was timed, the longer sound would produce a lower peak time; if the sound was not timed, the two durations of sound would produce the same peak time. The CR was lever-pressing during the sound. The sound was treated in various ways: presented alone (Experiments 1, 3, and 4), followed by food (Experiments 1, 3, and 4), preceded by food (Experiment 3), and followed by food after 20 s (Experiment 4). Treatments that produced no timing of sound produced no CR, and treatments that increased (or diseased) timing also increased (or decreased) the CR. The results suggest that there is overlap between the mechanisms that produce time discrimination and the mechanisms that produce classical conditioning.     

Measuring evaluative conditioning using the Implicit Association Test

When a neutral stimulus is paired with a stimulus that has strong affective properties, these properties often appear to be transferred to the neutral stimulus. This learning has been termed evaluative conditioning. In two experiments, participants first learned the ‘meanings’ of four non-words. Two of these meanings were affectively positive, and two were affectively negative. Transfer of affect was measured in the Implicit Association Test (IAT). In the IAT, a participant’s affective response to an item is inferred from his or her ability to categorise that item with other pleasant and unpleasant stimuli. An item easily categorised with other liked stimuli is deemed to be liked itself. In both experiments, evidence for transfer of affect was observed in the IAT. Thus, non-words given pleasant meanings in training (evaluative conditioning) were more easily categorised with pleasant than unpleasant personality characteristics, compared to non-words given unpleasant meanings. The results suggest that the IAT is a useful way to test for evaluative conditioning. It is both sensitive to the transfer of affective properties from one stimulus to another, and, because affect is measured indirectly, the results are unlikely to be due to the demand characteristics of the experiment.     

The prefrontal-thalamic axis and classical conditioning.

Using the New Zealand albino rabbit as an animal model, it has been determined that the medial prefrontal cortex is intimately involved in, and may be necessary for, acquisition of classically conditioned bradycardia. The interconnected nuclei of the medial thalamus, most notably the mediodorsal nucleus, conversely appear to be associated with the development of the tachycardia that accompanies classical conditioning of the eyeblink and nictitating membrane response. Neuroanatomical, electrophysiological, brain stimulation, and lesion data are reviewed, which support the conclusion that the prefrontal-thalamic axis is intimately involved in acquisition of classically conditioned visceral changes.