Compensatory Response to Anticipated Densities1

The coping processes associated with crowding stress were conceptualized as dynamic sequences of personal or situational adjustments and readjustments directed toward maintaining desired frequencies of social contact. By studying ongoing coping processes as subjects prepared for anticipated crowding, evidence of social withdrawal as a response to crowding was obtained. In addition, findings suggested that these processes were sensitive to change in the situation, seeking or avoiding interaction as anticipated group size changed. Subjects who were subsequently told that they would be interacting in small groups rather than in larger groups reported less crowding and discomfort than subjects whose anticipation of large group interaction was maintained. Furthermore, subjects whose expectations of large group interaction were disconfirmed increased facial regard for others following disconfirmation, indicating a greater willingness to interact. These findings were discussed as evidence of optimization processes governing desired levels of social contact, intimacy, and personal space.     

Interserial and intraserial interference processes in morning recall of mental sleep experience

This study investigated ways in which predictions from interference theory might explain partial or total failure in the morning recall of mental sleep experience (MSE) episodes reported after provoked night awakening. Interference could take place either between the contents of one MSE episode (intraserial interference) or between the contents of different MSE episodes (interserial interference) and would be more likely to affect morning recall where similar (i.e., interrelated) contents in MSEs are involved. If interference were mainly intraserial, in the morning there would be no change in the difficulty of retrieving interrelated contents, whereas, if it were mainly interserial, there would be increased difficulty in the retrieval of such contents. All the possible pairs of reports obtained by awakening 8 subjects four times in REM sleep during each of four experimental nights spaced at weekly intervals were scored for interrelated contents, using Clark's (1970) system of analysis of paired units, which operates by matching linguistic features. Results showed that interrelations in morning report pairs are as frequent as in night report pairs, maintaining the same linguistic characteristics and with little transfer of contents from one MSE to another. Overall these findings are compatible with the hypothesis that interference is primarily intraserial rather than interserial. It is consequently suggested that morning recall failure may be due to temporary blocking of retrieval.     

Recency effect in recall of a word list when an immediate memory task is performed after each word presentation

Subjects studied 12-word lists for free recall. During presentation of the lists, each word was followed by a supraspan sequence of digits, which the subjects tried to reproduce. This task, unlike those used in previous research with this continual distractor procedure, presumably taxed immediate memory capacity to the full. Nevertheless, the word recall data showed a pronounced recency effect. Moreover, the magnitude of the recency effect was found to be just as great with this task as with a more typical task in which the demands on immediate memory are likely to be fewer. These findings reinforce the emerging view that the recency effect need not be the product of immediate memory.     

Determination of a behavioral transfer function: White-noise analysis of session-to-session response-ratio dynamics on concurrent VI VI schedules

Six pigeons were exposed to concurrent variable-interval schedules in which the programmed reinforcer ratios changed from session to session according to a pseudorandom binary sequence. This procedure corresponded to the stochastic identification paradigm (“white-noise experiment”) of systems theory and enabled the relation between log response ratios in the current session and log reinforcer ratios in all previous sessions to be determined. Such dynamic relations are called linear transfer functions. Both nonparametric and parametric representations of these, in the form of “impulse-response functions,” were determined for each bird. The session-to-session response ratios resulting from the session-to-session pseudorandom binary variations in reinforcer ratios were well predicted by the impulse-response functions identified for each pigeon. The impulse-response functions were well fitted by a second-order dynamic model involving only two parameters: a time constant and a gain. The mean time constant was 0.67 sessions, implying that the effects of abrupt changes in log reinforcer ratios should be 96% complete within about five sessions. The mean gain was 0.53, which was surprisingly low inasmuch as it should equal the sensitivity to reinforcement ratio observed under steady-state conditions. The same six pigeons were subjected to a similar experiment 10 months following the first. Despite individual differences in impulse-response functions between birds within each experiment, the impulse-response functions determined from the two experiments were essentially the same.     

Effects of containment and closure policies on controlling the COVID‐19 pandemic in East Asia

Growing efforts have been made to pool coronavirus data and control measures from countries and regions to compare the effectiveness of government policies. We examine whether these strategies can explain East Asia’s effective control of the COVID‐19 pandemic based on time‐series data with cross‐correlations between the Stringency Index and number of confirmed cases during the early period of outbreaks. We suggest that multidisciplinary empirical research in healthcare and social sciences, personality, and social psychology is needed for a clear understanding of how cultural values, social norms, and individual predispositions interact with policy to affect life‐saving behavioural changes in different societies.     

A tuned-trace theory of interval-timing dynamics

Animals on interval schedules of reinforcement can rapidly adjust a temporal dependent variable, such as wait time, to changes in the prevailing interreinforcement interval. We describe data on the effects of impulse, step, sine-cyclic, and variable-interval schedules and show that they can be explained by a tuned-trace timing model with a one-back threshold-setting rule. The model can also explain steady-state timing properties such as proportional and Weber law timing and the effects of reinforcement magnitude. The model assumes that food reinforcers and other time markers have a decaying effect (trace) with properties that can be derived from the rate-sensitive property of habituation (the multiple-time-scale model). In timing experiments, response threshold is determined by the trace value at the time of the most recent reinforcement. The model provides a partial account for the learning of multiple intervals, but does not account for scalloping and other postpause features of responding on interval schedules and has some problems with square-wave schedules.     

Associative learning and elemental representation: II. Generalization and discrimination

This paper follows on from an earlier companion paper (McLaren & Mackintosh, 2000), in which we further developed the elemental associative theory put forward in McLaren, Kaye, and Mackintosh (1989). Here, we begin by explicating the idea that stimuli can be represented as patterns of activation distributed across a set of units and that different stimuli activate partially overlapping sets (the degree of overlap being proportional to the similarity of the stimuli). A consequence of this view is that the overall level of activity of some of the units representing a stimulus may be dependent on the nature of the other stimuli present at the same time. This allows an elemental analysis in which provision for the representation of configurations of stimuli is made. A selective review of studies of generalization and discrimination learning, including peak shift, transfer along a continuum, configural discrimination, and summation, suggests that the principles embodied in this class of theory deserve careful consideration and will form part of any successful model of associative learning in humans or animals. There are some phenomena that require an elemental/associative explanation.     

Negative mood,depressive symptoms,and major depression after smoking cessation treatment in smokers with a history of major depressive disorder

Negative mood, depressive symptoms, and major depressive episodes (MDEs) were examined in 179 smokers with a history of major depression in a trial comparing standard smoking cessation treatment to treatment incorporating cognitive-behavioral therapy for depression (CBT-D). Early lapses were associated with relatively large increases in negative mood on quit date. Mood improved in the 2 weeks after quit date among those returning to regular smoking but not among those smoking moderately. Continuous abstinence was associated with short- and long-term reductions in depressive symptoms. MDE incidence during follow-up was 15.3% and was not associated with abstinence. Unexpected was that CBT-D was associated with greater negative mood and depressive symptoms and increased MDE risk. Results suggest complex bidirectional associations between affect and smoking outcomes.     

The effects of aging and divided attention on memory for item and associative information

The present study examined how aging and divided attention influence memory for item and associative information. Older adults and younger adults working under full-attention conditions and younger adults working under divided-attention conditions studied unrelated word pairs. Memory for item information was measured by later recognition of the 2nd word in the pair, and associative information was measured by recognition of the entire pair. Both older adults in the full-attention condition and younger adults in the divided-attention condition performed more poorly than younger adults in the full-attention condition, with the deficit in associative information being greater than the deficit in item information. In addition, a differentially greater associative decrement was found for the older adults, as shown by their heightened tendency to make false-alarm responses to re-paired (conjunction) distractors. The results are discussed in terms of an age-related reduction in processing resources compounded by an age-related increase in older adults' reliance on familiarity in associative recognition memory.