Evidence of preliminary response preparation from a divided attention task

In a divided attention situation, preliminary response activations produced by stimuli on one channel were revealed through their effects on responses to stimuli on a secondary probe channel. Subjects performed concurrent but independent four-choice reaction-time tasks using the same four response fingers (middle and index fingers on both hands). In the main task, targets were large and small Ss and Ts, and medium-sized Ss and Ts sometimes appeared as distractors. Targets in the probe task were squares differing in location. A response to a probe square was faster if a distractor letter presented just before it had the same name as the target letter corresponding to that square (i.e., assigned to the same response key) than if the distractor letter had a different name--a result indicating that distractor letters cause partial response preparation. The timecourse of the effect demonstrated that preparation was based on preliminary information about distractor name that was available before distractor size had been determined. The results support models in which response preparation can sometimes begin before stimulus recognition has finished.     

Psychological dynamics and self-perceptions of vasectomy candidates.

Growing concern with population control has focused attention on various methods of contraception including vasectomy. Psychological research on this topic is scant, however. In this study, 9 vasectomy candidates who were undergoing the operation were compared to 9 husbands whose wives were about to have a tubal ligation. Their responses on the Marlowe-Crowne Social Desirability Scale and the Adjective Check List were compared. Most of the data showed no significant differences except on one scale of Counseling Readiness. The results, and others, indicate that vasectomy candidates may have a tendency to deny the anxiety connected with the operation due to its irreversible nature.     

Psychopathology scale of the Hutt adaptation of the Bender-Gestalt Test: reliability.

The test-retest reliability of the Hutt Adaptation of the Bender-Gestalt test was explored with a population of 40 process schizophrenics over a two-week interval. The total Psychopathology Scale Score was found to have high retest reliability for both male and female patients (rho = .87 for males and .83 for females). Moreover the three major components for the Scale were found to have high reliability, and fairly high reliabilities were obtained for patients scoring high as well as low on the Scale. Interjudge reliability was also found to be very high (rho = .895), confirming previous studies in this respect. On these grounds, the Scale offers promise both for clinical and research purposes.     

Attribution versus persuasion as a means for modifying behavior.

The present research compared the relative effectiveness of an attribution strategy with a persuasion strategy in changing behavior. Study 1 attempted to teach fifth graders not to litter and to clean up after others. An attribution group was repeatedly told that they were neat and tidy people, a persuasion group was repeatedly told that they should be neat and tidy, and a control group received no treatment. Attribution proved considerably more effective in modifying behavior. Study 2 tried to discover whether similar effects would hold for a more central aspect of school performance, math achievement and self-esteem, and whether an attribution of ability would be as effective as an attribution of motivation. Repeatedly attributing to second graders either the ability or the motivation to do well in math proved more effective than comparable persuasion or no-treatment control groups, although a group receiving straight reinforcement for math problem-solving behavior also did well. It is suggested that persuasion often suffers because it involves a negative attribution (a person should be what he is not), while attribution generally gains because it disguises persuasive intent.     

Trigeminal nerve and eating in the pigeon (Columba livia): neurosensory control of the consummatory responses.

Electrophysiological, neurobehavioral, and cinematographic techniques were used to study the role of the trigeminal nerve in the neurosensory control of eating. Analaysis of single-unit data recorded in the pigeon's trigeminal ganglion indicates that the trigeminal nerve provides somatosensory inputs from the oral region that signal the location and movement of food and monitor the extent of mouth opening. Trigeminal deafferentation, although it does not affect pecking or swallowing, severly impairs the efficiency of eating. Cinematographic analysis shows that the impairment is due to disruption of the neurosensory control of mandibulation-the process by which grain is grasped at the beak tip and moved to the back of the mouth.     

Thresholds for the perception of angular acceleration as indicated by the oculogyral illusion

A motorized chair (with precise servo controls) accelerated the observer in a clockwise (CW) or counterclockwise (CCW) direction at rates that ranged in logarithmic progression from 0.02 to 6.00 deg/sec². The target, a narrow collimated Line of light, was contained within a goggle device worn by the observer and therefore fixed in relative position to him. The illusion, appearing as rightward or leftward movement of the visual target in the direction of acceleration, was determined by a double staircase procedure among 300 normal and 4 labyrinthine-defective observers. None of the latter perceived the illusion. The majority of normal observers revealed no substantial directional difference (CW vs. CCW threshold). Threshold frequency distributions ranged in rate (deg/sec²) from 0.020 to 0.950; the threshold of response in more than half the normal observers was less than 0.10, in over three-fourths was less than 0.20, in over 90% less than 0.30, and 100% less than 1.00.     

Compounding of discriminative stimuli that maintain responding on separate response levers

In Experiment 1, rats' responses were reinforced on a fixed-interval 30-sec schedule in the presence of either a light or a tone and were not reinforced in their absence. Each stimulus was correlated with its own response lever, with only one lever present during a session. When light and tone were compounded in the presence of the tone-correlated lever, no change in responding occurred. However, when tone was compounded with light in the presence of the light-correlated lever, level of responding was greater than to light alone (response summation). Summation was also found when each stimulus was correlated with the same lever. Next, light and tone were again correlated with separate levers, but both levers were always simultaneously present. Compounding produced both summation and emission of most responses on the light-correlated lever. This prepotency of light was reduced (1) by leaving a houselight on throughout the session; and (2) by correlating each stimulus with a different schedule (either fixed-interval 4.7-sec or fixed-interval 30-sec). With a medium- and high-intensity houselight and with the different reinforcement schedules, similar results were obtained during compounding, regardless of whether compounding occurred in the presence of the light- or tone-correlated lever.