Regression analyses of repeated measures data in cognitive research

Repeated measures designs involving nonorthogonal variables are being used with increasing frequency in cognitive psychology. Researchers usually analyze the data from such designs inappropriately, probably because the designs are not discussed in standard textbooks on regression. Two commonly used approaches to analyzing repeated measures designs are considered in this article. It is argued that both approaches use inappropriate error terms for testing the effects of independent variables. A more appropriate analysis is presented, and two alternative computational procedures for the analysis are illustrated.     

Properties of memory for unattended spoken syllables

Whereas previous studies on memory for unattended speech have inadvertently included acoustic interference, the present study examines memory for unattended syllables during a silent period of 1, 5, or 10 s. The primary task was to read silently (Experiments 1-3) or whisper the reading (Experiment 4). Occasionally, when a light cue occurred, the subject was to recall the most recent spoken syllable, as well as the recent reading material. Memory for both the vowels and consonants of the syllables decreased across 10 s, confirming that auditory memory does decay in the absence of acoustic interference. However, the specific patterns of memory decay for vowels versus consonants depended on task demands, including the allocation of attention and the opportunity for subvocal coding. We suggest an account of performance that includes auditory sensory and phonetic memory codes with different properties, used in combination.     

Maintaining social identity in a mixed-gender setting: Minority/majority status and cooperative/competitive feedback

This study tested the applicability of Tajfel and Turner's (1986) Social Identity Theory (SIT) to cooperative behavior in a mixed-gender setting. SIT suggests that as a “socially subordinate” group in a male-dominated society, women, when their gender is in the numerical minority, will engage in social competition in an attempt to enhance social identity. However, gender-based socialization may encourage men toward competition and women toward cooperation, regardless of group gender composition. In this study, male and female subjects were assigned to a six-person mixed-gender group in which their gender was either in the numerical minority or majority, and performed an interactive task under either cooperative or competitive feedback. An interaction of sex and feedback showed males in the cooperative feedback condition responded more competitively than did males in the competitive feedback condition, while females were equally cooperative in both feedback conditions. Feedback also interacted with the numerical ingroup/outgroup gender balance. While competitive feedback elicited little variation in subjects' responses across the ingroup/outgroup balance variable, the cooperative condition elicited greater competition from subjects in the numerical minority and greater cooperation from those in the numerical majority. Results were interpreted as partial support for SIT, while stressing the need for further investigation into gender as a unique influence on intergroup behavior.     

Factor analysis of the revised UCLA loneliness scale

The Revised UCLA Loneliness Scale (R-UCLA) is described and used as a unidimensional measure of loneliness; conceptualizing and assessing loneliness as a unitary, global experience. The present study suggests that the R-UCLA is a multidimensional measure of loneliness that assesses more than one construct of the loneliness experience. Results of principal axis factor analysis suggest that the R-UCLA measures three dimensions of loneliness: loneliness related to (a) “intimate others,” (b) “social others,” and (c) the “affiliative environment.” These findings may affect the utilization of the R-UCLA in future assessment, research, and intervention. These implications are discussed. This article is based on the author’s master’s thesis, submitted for the Master of Counseling degree at Arizona State University. This research was supported by a grant from the Arizona State University Graduate Student Association Research Development Program.     

Social transmission of food preferences in Japanese monkeys (Macaca fuscata) after mere exposure or aversion training

In Experiment 1, 3 mother-child pairs of Japanese monkeys (Macaca fuscata) were given simultaneous choice tests between raisins and popcorn. The mothers and offspring showed different choice patterns. Cofeeding opportunities were then alternated with individual choice tests. In Experiment 2,2 other pairs were added. Each animal was again offered simultaneous choice tests between marshmallows and almonds. Food aversion conditioning was used to create different choice patterns for mothers and offspring. After cofeeding and choice tests, the differences in choice patterns disappeared in both experiments. The changes after contact with the other's eating pattern during cofeeding was as follows: foods consumed by either came to be eaten by both; foods consumed by both continued to be eaten by both; and foods consumed by neither continued to be ignored. The results provide evidence for social transmission of food preferences in this species.     

Failure to detect changes to attended objects in motion pictures

Our intuition that we richly represent the visual details of our environment is illusory. When viewing a scene, we seem to use detailed representations of object properties and interobject relations to achieve a sense of continuity across views. Yet, several recent studies show that human observers fail to detect changes to objects and object properties when localized retinal information signaling a change is masked or eliminated (e.g., by eye movements). However, these studies changed arbitrarily chosen objects which may have been outside the focus of attention. We draw on previous research showing the importance of spatiotemporal information for tracking objects by creating short motion pictures in which objects in both arbitrary locations and the very center of attention were changed. Adult observers failed to notice changes in both cases, even when the sole actor in a scene transformed into another person across an instantaneous change in camera angle (or “cut”).     

Chicks Injected with Antisera to either S-100α or S-100β Protein Develop Amnesia for a Passive Avoidance Task

The cellular expression of S-100β protein is upregulated in Alzheimer's disease and in Down's syndrome, and this protein has been implicated in memory-related processes in laboratory animals. However, the possibility that the α subunit of S-100 is also involved in memory has not yet been examined. In the present study, day-old black Australorp white Leghorn cockerel chicks (Gallus domesticus) received injections of monoclonal antisera to S-100α (1:50) or S-100β (1:500) into each hemisphere immediately after training on a one-trial passive avoidance task. The chicks displayed significantly lower retention levels than control birds that had been injected with antisera to carbonic anhydrase, or with saline (p< .01). S-100α antisera had an amnestic effect when injected between 0 and 20 min after training, with memory deficits occurring from 30 min postlearning, at the point of transition between the A and the B phases of the Gibbs-Ng intermediate memory stage. By contrast, the S-100β antisera needed to be injected either 5 min before or immediately after training and produced amnesia 10 min earlier, at the start of the A phase of the intermediate memory stage. We conclude that the two subunits of the S-100 protein are required at different points in the sequence of events leading to the consolidation of passive avoidance memory.