Revaluation manipulations produce emergence of underselected stimuli following simultaneous discrimination in humans

Stimulus overselectivity occurs when only one of potentially many aspects of the environment controls behaviour. In four experiments, human participants were trained and tested on a trial-and-error simultaneous discrimination task involving two two-element compound stimuli. Overselectivity emerged in all experiments (i.e., one element from the reinforced compound controlled behaviour at the expense of the other). Following revaluation (extinction) of the previously overselected stimulus, behavioural control by the underselected stimulus element emerged without any direct training of that stimulus element. However, while a series of extinction manipulations targeting the revaluation of the overselected stimulus produced differential extinction of that stimulus, they did not result in differential emergence of the previously underselected stimuli. The results are discussed with respect to the theoretical implications for attention-based accounts of overselectivity

Airglow and aurorae from Dome A, Antarctica

Despite the absence of artificial light pollution at Antarctic plateau sites such as Dome A, other factors such as airglow, aurorae and extended periods of twilight have the potential to adversely affect optical observations. We present a statistical analysis of the airglow and aurorae at Dome A using spectroscopic data from Nigel, an optical/near-IR spectrometer operating in the 300-850 nm range. The median auroral contribution to the B, V and R photometric bands is found to be 22.9, 23.4 and 23.0 mag arcsec-2 respectively. We are also able to quantify the amount of annual dark time available as a function of wavelength; on average twilight ends when the Sun reaches a zenith distance of 102.6°.2 page(s

Emotional Intelligence and Transformational and Transactional Leadership: A Meta-Analysis

The purpose of this study is to evaluate claims that emotional intelligence is significantly related to transformational and other leadership behaviors. Results (based on 62 independent samples) indicated a validity estimate of .59 when ratings of both emotional intelligence and leadership behaviors were provided by the same source (self, subordinates, peers, or superiors). However, when ratings of the constructs were derived from different sources, the validity estimate was .12. Lower validity estimates were found for transactional and laissez-faire leadership behaviors. Separate analyses were performed for each measure of emotional intelligence. Trait measures of emotional intelligence tended to show higher validities than ability-based measures of emotional intelligence. Agreement across ratings sources for the same construct was low for both transformational leadership (.14) and emotional intelligence (.16)