Group Dynamics in Janis's Theory of Groupthink: Backward and Forward

Janis's groupthink theory is an appealing explanation of how group process can get in the way of optimal decision making. Unfortunately, Janis was selective and not always consistent in his application of research in group dynamics. This paper traces groupthink to its theoretical roots in order to suggest how a broader and more consistent use of research in group dynamics can advance understanding of decision-making problems. In particular, the paper explores and reinterprets the groupthink prediction that poor decision making is most likely when group cohesion is based on the personal attractiveness of group members.     

Posttraining Electrical Stimulation of Vagal Afferents with Concomitant Vagal Efferent Inactivation Enhances Memory Storage Processes in the Rat

Peripherally administered or released substances that modulate memory storage, but do not freely enter the brain, may produce their effects on memory by activating peripheral receptors that send messages centrally through the vagus nerve. Indeed, vagus nerve stimulation enhances memory performance, although it is unclear whether this effect is due to the activation of vagal afferents or efferents. To eliminate the possible influence of descending fibers on memory storage processes, rats were implanted with cuff electrode/catheter systems along the left cervical vagus. Forty-eight hours following surgery, each animal received a 3.0-μl infusion (1.0 μl/min) of either lidocaine hydrochloride (75.0 mM) or isotonic saline below the point of stimulation. Animals were then trained 10 min later on an inhibitory-avoidance task with a 0.75-mA, 1.0-s foot shock. Sham stimulation or vagus nerve stimulation (0.5-ms biphasic pulses; 20.0 Hz; 30 s; 0.2, 0.4, or 0.8 mA) was administered immediately after training. Memory, tested 24 h later, was enhanced by stimulation whether descending vagus nerve fibers were inactivated or not. Both lidocaine- and saline-infused groups showed an intensity-dependent, inverted-U-shaped pattern of retention performance, with the greatest effect observed for 0.4 mA (U= 9,p< .05, andU= 7,p< .01, respectively). Additionally, animals that received lidocaine infusions, but no vagus nerve stimulation, showed impaired memory compared to the performance of saline-infused control animals (U= 11,p< .05). Together, these findings suggest that vagal afferents carry messages about peripheral states that lead to the modulation of memory storage and that the memory-enhancing effect produced by vagus nerve stimulation is not mediated via the activation of vagal efferents.     

Beliefs and Experiences of Bereaved Teenagers: some spiritual and moral issues

When people die it is quite common for the bereaved to think about where they have gone and to maintain links with them in some way. Traditional Christian beliefs about ‘heaven’ and ‘hell’ may be revised and other ideas about spiritual continuity are often explored. This article will discuss responses from 94 11‐17‐year‐olds (38 males/56 females) regarding circumstances of and reasons given for a death; explanations and support; religious affiliation and belief in God; answers to the question ‘Why do people die?’ and ‘What happens after death?'; experiences of having a sense of the presence of the deceased; and personal qualities, attitudes towards other people and views of life. It will conclude by reassessing some of the moral and spiritual issues raised.     

Word frequency and list composition effects in associative recognition and recall

The effects of list composition and word frequency on cued recall, associative recognition, and item recognition were examined in three experiments For pure-frequency lists, cued recall and associative recognition show better performance on common high-frequency (HF) words than on rare low-frequency (LF) words. Item recognition, however, shows an advantage for LF words. In mixed lists, consisting of half HF and half LF words, the HF advantage in cued recall disappeared; however, the word frequency effects in item and associative recognition were unchanged. These results are inconsistent with explanations based on differential attention or co-rehearsal of KF and LF words. However, the results are consistent with list strength results which show that recognition is insensitive to strength-based list composition, but that recall is sensitive to list composition.     

Changes in subject performance during the semester: An empirical investigation

Two experiments were conducted to probe for performance differences between early-semester subjects and late-semester subjects in an introductory psychology subject pool. In Experiment 1A, hypotheses regarding changes in performance included differential effort, changes in subjects’ attention to the task, and changes in subjects’ sensitivity. A signal detection paradigm was used, and 278 subjects were sampled over the course of the semester. No evidence of changes in subject performance was found, in spite of sufficient power to detect relevant patterns of change. The results of a replication (N = 135) were consistent with those of Experiment 1A. Experiment 2 (N = 118) employed a text comprehension task to examine possible differences in subject performance with a more cognitive task. Again, there was no evidence to support the idea that late-semester subjects were performing differently from early-semester subjects.     

Affect, accessibility of material in memory, and behavior: a cognitive loop?

Two studies investigated the effect of good mood on cognitive processes. In the first study, conducted in a shopping mall, a positive feeling state was induced by giving subjects a free gift, and good mood, thus induced, was found to improve subjects' evaluations of the performance and service records of products they owned. In the second study, in which affect was induced by having subjects win or lose a computer game in a laboratory setting, subjects who had won the game were found to be better able to recall positive material in memory. The results of the two studies are discussed in terms of the effect that feelings have on accessibility of cognitions. In addition, the nature of affect and the relationship between good mood and behavior (such as helping) are discussed in terms of this proposed cognitive process.     

Empirically derived groups in the assessment of recovery from aphasia.

This paper examines the pretreatment intercorrelation matrix of the subtests of the Porch Index of Communication Ability to derive factors reflecting components of language impairment. In addition to a general factor reflecting overall language dysfunction, five specific factors reflecting verbal competency (fluency), graphic-verbal expression, gestural-verbal expression, gestural-nonverbal comprehension, and graphic-geometric comprehension were found which accounted for 90.6% of the total variance. A cluster analysis of the five pretreatment factor scores yielded six groups which accounted for 79% of the variance for these factors. These groups were differentiated primarily in terms of impairment and showed a high rate of accuracy prediction for group membership (97.5%). These groups were extremely stable, as shown by the 75% accurate prediction rate derived from the post-treatment factor scores. The effectiveness of this model in generating homogeneous and highly discriminable groups based on objective measures of the patient's language functions indicates that classification of patients into empirical groups should be a major concern of any research design. Implications for assessing effectiveness of therapeutic intervention and the design of test battery were also discussed.     

Judgment Processes and Interpersonal Conflict Related to Societal Problem Solutions1

An application of multidimensional scaling to judgments about potential solutions to the overpopulation problem yielded two dimensions: Voluntary versus involuntary and economic versus noneconomic. The location of the “solutions” in this two dimensional space was closely related to their judged acceptability, for both original and cross-validation samples. The two-dimensional coordinates of the “solutions” were then used as implicit cue values in a “lens model” analysis of potential conflict among the subjects. This analysis indicated that judgmental inconsistency was likely to be the major source of conflict for these subjects.