An N-channel stroboscopic tachistoscope for typewritten stimuli

The n-channel tachistoscope described employs the principle of “stopping” a continuously moving list of words by means of stroboscopic flashes of light. It can present as many as 50 stimuli per trial at any rate between 5 and 40 items per second. Stimulus materials can be prepared on an electric typewriter. It provides only partial control over the various time parameters.     

Form and characteristics of the cardiovascular conditional response in Rhesus monkeys

Three Rhesus monkeys restrained in primate chairs were exposed to several Pavlovian control procedures, followed by 13 sessions of cardiac conditioning under a delay paradigm. The conditional stimulus (CS) was a vertical line and the unconditional stimulus (US) was electric foot shock. Heart rate (HR) was analyzed in successive fivesecond intervals beginning five seconds before CS onset. The major finding was that the conditional response was consistently biphasic and consisted of an initial acceleration followed by deceleration toward the baseline, but rarely reaching it before onset of US. The subjects differed in magnitude of acceleration and subsequent deceleration as well as the location of the maximum rate in the CS-US interval. A breakdown of trials on the basis of the pre-CS HR revealed that the magnitude of effect was inversely related to the pre-CS rate.     

Physiologic and motor conditioning and generalization in children with minimal brain dysfunction

Twenty-six children diagnosed as having minimal brain dysfunctions (MBD) were compared with 26 controls in a conditinoing and generalization procedure. Skin resistance, heart rate, and muscle action potentials were monitored throughout. Success involved learning which of two tones signalled the accessibility of a penny. Whereas 92 per cent of controls reached the criterion of five successive correct responses, only 62 per cent of MBD’s did. Further, a third of the MBD’s were so maladaptive as to force procedural variations, while only a few minor irregularities occurred with the controls. Quality of performance was related to age, intelligence, and ability to discriminate and remember tones. Controls were more physiologically reactive than MBD’s, especially in skin resistance. Physiologic differentiation of the two tones was significant in both groups of children and appeared concurrently with motor differentiation. The only evidence of physiologic generalization was in the SR data of controls. The possibility that defective arousal structures, or defective coupling of arousal structures and other perceptual and motor structures, could account for the decreased physiologic reactivity, short attention spans, and poor concentration ofsome MBD’s is discussed. This research, in conformity with other laboratory studies of the brain, indicates that motivational as well as cognitive defects may be organically based.     

Two methods for obtaining electrocardiograms of chair-restrained monkeys

EKG’s of chair-restrained Rhesus monkeys were recorded using 1. implantation of subdermal electrodes, and 2. surface electrodes. Both procedures resulted in reliable registration of EKG’s in experiments involving both Pavlovian and instrumental conditioning and recording. The advantages and disadvantages of the methods are discussed and detailed instructions for implementation are given.     

Evoked potentials and stages of information processing: Methods of analysis

The use of principal components analysis (PCA) for the study of evoked-response data may be complicated by variations from one trial to another in the latency of underlying brain events. Such variation can come from either random intra-and intersubject variability or from the effects of independent variables that are manipulated between conditions. The effect of such variability is investigated by simulation of these latency-varying events and by analysis of evoked responses in a behavioral task, the Sternberg memory search task, which is well known to generate variation in the latency of brain events. The results of PCA of within-subjects differences in these two situations are plausibly related to underlying stages of information processing, and the technique may augment reaction time data by providing information on the time of occurrence as well as the duration of stages of information processing.     

MacLaboratory Controller: A switch and A/D interface between Apple’s Macintosh and peripheral apparatus

Apple’s Macintosh microcomputer has advantages over other systems used for laboratory control and data acquisition, especially because of its graphic and user-friendly features. However, a major perceived limitation has been its closed architecture. We describe an interface using the RS 422 modem port that supports up to 64 input/output (I/O) functions including analog-to-digital 4–12 channel input. The Controller software supplies an easily edited authoring tool in which functional relationships, logical operators, timing (millisecond accuracy), and counting functions are established through simple mouse and menu commands. Data from I/O functions may be displayed or saved as tab-delimited files that can be opened by various Macintosh statistical and spreadsheet packages and that are transportable to some mainframe applications.     

The cognitive-somatic anxiety questionnaire: Psychometric and validity data

The Cognitive-Somatic Anxiety Questionnaire (CSAQ) is a 14-item self-report inventory that is divided into two 7-item scales (Cognitive and Somatic) that appear to reflect cognitive or somatic anxiety. In an attempt to evaluate the construct validity of this multidimensional instrument, the CSAQ was administered to 109 college students along with several other measures of physical and psychological symptoms. The results suggest that (a) despite considerable overlap between the Cognitive and the Somatic scales (r=.62), an exploratory factor analysis is able to identify a single large somatic factor along with three lesser cognitive-appearing factors, and (b) the correlations with concurrent measures of related constructs provide some limited evidence of the construct validity of the CSAQ. For males, both the Cognitive and the Somatic scales of the CSAQ correlated significantly with several anxietyrelated measures. However, for females CSAQ scores correlated less consistently with the other test scales, although Somatic scale scores for females were positively related to measures of health and exercise involvement. Suggestions for improving the CSAQ are offered.     

The influence of individual characteristics and severity of harassing behavior on reactions to sexual harassment

Differences in reactions to 18 scenarios depicting potentially sexually harassing situations were studied as a function of harassment severity and individual level factors. The scenarios illustrate a continuum of behavior, with some situations depicting overt sexual harassment and others portraying more innocuous behaviors. The individuals' reactions were strongly influenced by the perceived severity of the incidents. Reactions were influenced to a lesser extent by the individual level factors of gender, attitudes toward women, religiosity, and locus of control. Among these factors, gender had the strongest effect on reaction types. Findings indicate that harassment severity and individual level factors may combine to influence reactions to sexual harassment.The authors would like to thank Barbara Gutek and Gary Powell for their comments on an early draft of this paper.