Effects of topic valence and pictorial distractor valence on verbalizing and evaluating topic-evoked visual imagery

We reasoned that if speakers must decide how long to reflect and how much to say about a topic, they use such guidelines as topic valence and valent situational distractors that compete for attention. We hypothesized that latency and extent of verbalization would be greater if topic valence were relatively negative, in that negative topics are “weightier” and hence deserve longer reflection and verbalization. Similarly, a negative distractor would cast a weightier aura over the task, with parallel effects. While subjects were imagining the visual scene evoked by a certain pleasant or unpleasant topic, a pleasant or unpleasant picture appeared toward the left or right, on a screen. After the picture faded subjects described the topic-evoked image. Topic valence had no effect on speech latency, whereas picture valence had the predicted effect. Negative topics increased latency of visual attention to pictures, though, as expected, subjects then looked sooner at negative pictures. Both topic valence and picture valence had the predicted effects on extent of verbalization. As predicted, too, unpleasant pictures elicited relatively negative evaluations of topic-evoked images.     

Seasonal variations in the birth of left-handers: another look

An attempt was made to replicate a reported seasonal variation in the birth of left-handed females. The observed number of births per month (as well as season) did not depart from the number expected by chance. This is the second failure to observe the reported overrepresentation of November births.     

Computer-aided instruction in a physiological psychology course

A simulation/tutorial sequence was introduced into an undergraduate physiological psychology class (N=32) to provide a laboratory experience. The college computer center managed the IBM-PC-compatible networked facility. The sequence included neuroanatomy, stereotaxic surgery, histology, electrical self-stimulation, and use of the polygraph. All the software was off the shelf except for the stereotaxic surgery/histology/self-stimulation package, which was written by the authors using ToolBook running under Windows.     

Sinusoidal plucks and bows are not categorically perceived,either

Cutting and Rosner (Perception & Psychophysics, 1974,16, 564–570) reported that two acoustic nonspeech continua varying in rise time were categorically perceived. We have already shown (Rosen & Howell,Perception & Psychophysics, 1981,30, 156–168) that the reason their sawtooth continuum was perceived in such a way, and in particular why it exhibited a midcontinuum peak in the discrimination function, was entirely due to the stimuli not having the intended rise times. The other nonspeech continuum that varied in rise time and was reported to be categorically perceived used a sinusoidal carrier. Although the labeling functions obtained were not as sharp as those obtained with sawtooth stimuli, the characteristic midcontinuum discrimination peak was found. We generated such a set of sinusoidal stimuli and found no evidence of categorical perception. Just as we have previously found for sawtooth stimuli, discrimination is best at the short rise-time end of the continuum and decreases monotonically with increasing rise time.     

Behavioral assessment of psychiatric inpatients and normal controls across different environmental contexts

Objectively defined, publicly observable behaviors were time sampled for hospitalized psychiatric patients and normal controls in three distinct environmental contexts: lunch time, free time, and gym time. The behaviors sampled included body activity, extremity activity, proximity, social interactions, participation, visual scanning, laughing/smiling, and idiosyncratic behavior. Patient behaviors were recorded during both a drug-free baseline period and a subsequent medication period. The data suggest that consistent and reliable differences between patients and normals in most behaviors can be observed and that environmental context is an important determinant of these differences. Results are discussed in terms of their implications for assessment procedures and treatment decisions.These investigations were supported in part by State of Illinois Department of Mental Health and Developmental Disabilities Grants RD836-13 and RD622-02 to the first author. The cooperation of the Illinois State Psychiatric Institute staff is gratefully acknowledged.     

Maintenance of grip-induced muscle tension: a behavioral marker of schizophrenia.

A grip-induced muscle tension maintenance task distinguished between schizophrenic patients, regardless of medication or hospitalization status, and both normals and controls with affective (unipolar and bipolar) disorders. Unaffected first-degree relatives of schizophrenic patients also showed a grip deficit. Coupling the grip task with a visual discrimination task that divided attention through instruction or reinforcement contingency, increased grip error times for all groups. No group differences appeared on the discrimination task, regardless of difficulty level, and the tone used to provide corrective feedback was not implicated in the grip deficit. The results suggest that the grip task is tapping, in a systematic and reliable manner, a motor-control abnormality that may be useful as a behavioral marker of schizophrenia.