Andrew Crider

A selective attention deficit in the rat following induced dopamine receptor supersensitivity

In the blocking paradigm, prior training to one conditioned stimulus (CSA) blocks the ability to attend to a second conditioned stimulus (CSB) when the two form a compound (CSAB) in subsequent training. Blocking is an associative process by which animals learn to ignore CSB because it contains no new information regarding the reinforcing event. In Experiment 1, dopamine (DA) receptor supersensitivity was induced in rats by prolonged pretreatment with haloperidol. The animals with DA receptor supersensitivity failed to show blocking by responding equivalently to both elements of the CSAB compound. This effect was replicated in Experiment 2, which also tested for an arousal interpretation of disrupted blocking by introducing a novel stimulus following training. Supersensitive rats were no more responsive to this novel stimulus than were control animals, which supports a selective attention deficit interpretation of disrupted blocking with DA receptor supersensitivity. This attentional deficit resembles behavioral perseverations induced by DA agonists.

Personality and Electrodermal Response Lability: An Interpretation

Electrodermal response (EDR) lability is a psychophysiological trait reflecting stable individual differences in electrodermal activation as indexed by frequency measures of phasic EDR activity. There is no consistent evidence that EDR lability reflects dispositional or clinical anxiety. However, EDR lability appears to be related to individual differences in the overt expression of emotional and antagonistic impulses. Greater EDR lability is associated with a relatively undemonstrative and agreeable disposition, whereas greater EDR stability is associated with a relatively expressive and antagonistic disposition. The inverse relationship between EDR lability and the expression of emotional and antagonistic impulses suggests that EDR lability may reflect individual differences in the effortful control of such expression. This hypothesis is consistent with cognitive effort interpretations of phasic EDR activity, with evidence of the sensitivity of phasic EDR activity to capacity-demanding tasks, and with evidence of reduced spare capacity among EDR labile individuals under cognitive challenge. Individual differences in effortful self-control may explain the association of greater EDR lability with essential hypertension and greater EDR stability with forms of antisocial behavior.

Interaction of tail-pressure stress and d-amphetamine in disruption of the rat's ability to ignore an irrevelant stimulus.

Rats received either 0 or 30 preexposures to a tone that was later used as a warning stimulus in a two-way active avoidance task. Consistent with previous data, tone preexposure resulted in retarded acquisition of the conditioned avoidance response (CAR) in saline control animals and in animals that received chronic administration of a low dose of d-amphetamine. Similarly, animals that received tail-pressure stress prior to stimulus preexposure also showed retarded acquisition of the CAR. However, animals that received a combination of tail pressure and d-amphetamine did not show retarded CAR acquisition following stimulus preexposure. These results suggest an interaction between environmental stressors and d-amphetamine in producing attentional deficits.

Electrodermal Response Lability-Stability: Individual Difference Correlates

The aim of this chapter is to review a sizable literature on electrodermal response (EDR) lability considered as an individual difference phenomenon. The exposition is divided into three parts. The first deals with questions of definition and measurement the second presents a first-order and an extended hypothesis regarding likely personality correlates, and the third reviews evidence for interpreting EDR lability as a concomitant of individual differences in characteristic levels of arousal along a sleep-wakefulness continuum.

Overcoming Fragmentation in the Undergraduate Psychology Curriculum

Fragmentation, all too apparent to students, has the unsettling effect of obscuring underlying problems that are really common to sub-areas.