A method for electronically monitoring the ambulatory activity of honeybees under dark conditions

An electronic apparatus using infrared beams for monitoring the movements of individual bees under dark conditions is described. The searching behavior of workers in an arena was monitored over 2-h periods. Mean ambulatory velocity for one bee over a distance of 100 mm was 45.6±1.51 mm/sec (n=45). Thigmokinesis and temporal activity patterns are illustrated.     

The Role of Status in Producing Depressed Entitlement in Women's and Men's Pay Allocations

Extensive empirical evidence confirms a depressed entitlement effect wherein women pay themselves less than men for comparable work and believe the allocation fair. The present study tests the hypothesis that status subordination linked to being female underlies at least some of this effect. A 2 × 3 design crossed 180 undergraduates' gender with a control condition, which successfully established the depressed entitlement effect, and two experimental conditions. In one, women's status was enhanced through legitimation of women's task abilities; in the other, both women's and men's status was enhanced by adding educational credentials relevant to task ability. Follow-up analyses of the significant interaction revealed that the gap in self-pay demonstrated in the control condition disappeared when women's status was enhanced such that higher-status women's self-pay equaled that of men and exceeded that of control women. Although these findings confirm that status plays a role in producing depressed entitlement in self-pay, ancillary analyses of participants' perceptions point to the persistence of shifting standards and men's resistance to status threats.     

Observing responses in rats: Support for the secondary reinforcement hypothesis

Rats' lever presses on a retractable lever earned brief presentations of discriminative stimuli signalling periods in which responding on an alternative lever was either non-reinforced (extinction) or reinforced on a random ratio schedule. The predictions of two theoretical accounts of this behaviour were tested by studying the effects of omitting either the stimulus signalling the reinforced or that signalling the non-reinforced schedule component. Under these conditions rats' behaviour is determined by the conditioned, affective properties of the stimuli rather than by their purely informational properties.     

Binocular cues in the perception of distance of a point source of light

The ability to make egocentric distance estimates of a single point source of light, seen in darkness and without the cues of changing size and luminance, was investigated in sixteen observers. The attenuation required to maintain constant luminance, when the target was viewed from different distances, was shown to follow the inverse square law providing the angle subtended by the light was less than 20 s arc. Distance changes were also simulated by means of a split mirror which produced vergence cues, or by test lenses to provide accommodation cues. Over the range 0.5 to 9.2 m distance estimates were surprisingly accurate, although there was some overestimation of near and underestimation of far distances. Most observers made good judgements when only convergence cues were varied, whereas no observers made consistently good judgements when only accommodation cues were varied. The difficulties are discussed in terms of the accommodation-convergence link. When distance was simulated by changing convergence and accommodation cues, estimates were not as good as when real distance was changed. Since good estimates were made with brief target exposures, these judgements were not based on subsequent convergence or accommodation changes. It is suggested that the metric or reference against which the apparently absolute judgements were made was the efferent demand signal associated with a 'resting' position of convergence in darkness.