Some aspects of the motor organization of the oculomotor system

Oculomotor responses in looking to visual targets were examined for motor coordination parallel to that found in manual pointing. ocular responses did not show any evidence that speed-accuracy tradeoff when the correlation of latency (reaction time) and accuracy was assessed. The oculomotor system did show a range effect, hidden under a general undershoot of target position and present only when no visual feedback about target position was available to allow correction during the movement. Cues to allow predictive timing of the response seemed very important for oculomotor reaction time. processing of timing of movement may be handled differently for oculomotor than for manual orienting, and calculation of position in space may be processed in common, leading to both similarities and differences for the two motor systems.     

The motion aftereffect

The motion aftereffect is a powerful illusion of motion in the visual image caused by prior exposure to motion in the opposite direction. For example, when one looks at the rocks beside a waterfall they may appear to drift upwards after one has viewed the flowing water for a short period-perhaps 60 seconds. The illusion almost certainly originates in the visual cortex, and arises from selective adaptation in cells tuned to respond to movement direction. Cells responding to the movement of the water suffer a reduction in responsiveness, so that during competitive interactions between detector outputs, false motion signals arise. The result is the appearance of motion in the opposite direction when one later gazes at the rocks. The adaptation is not confined to just one population of cells, but probably occurs at several cortical sites, reflecting the multiple levels of processing involved in visual motion analysis. The effect is unlikely to be caused by neural fatigue; more likely, the MAE and similar adaptation effects provide a form of error-correction or coding optimization, or both.     

Father-absent women: Self-concept and modes of relating to men

Four groups of college-age women were used to determine the relationship between absence of father in childhood and adult self-concept and interpersonal relationships with men. Groups consisted of 15 father-present subjects who came from intact homes; 15 father-absent (FA) subjects with no older brothers who experienced the death of their father early in life; 15 FA subjects with no older brothers who experienced father loss due to divorce; and 12 FA subjects with one or more older brothers whose parents were divorced. The Tennessee Self-Concept Scale and a self-report questionnaire of modes of relating to men were the dependent variable measures. Results revealed no significant differences among groups in most areas of self-concept or interpersonal relationships with both older and age-peer men. Only in social self-concept and nurturance behavior with age-peer men were significant differences observed. Thus, only partial support of the hypotheses of differences was obtained. Reasons for the departure between earlier and present results are proposed.This article is based on a master's of arts thesis completed by the first author (now at the University of Utah) under the direction of the second author.     

Adaptation to visual rearrangement: Role of sensory discordance

The relative contributions of proprioceptive and efferent information in eliciting adaptation to visual rearrangement were studied under two conditions of visual stimulation. Subjects permitted sight of their forearm under normal room illumination showed significant adaptation when the forearm was (a) moved up and down under the action of tonic vibration reflexes, (b) voluntarily moved through the same trajectory at the same pace, (c) viewed while still, and (d) viewed while the margins of the elbow were vibrated. The reflex movement condition elicited significantly greater adaptation than the other conditions. Subjects allowed only sight of a point source of light attached to their hand showed significant adaptation when the forearm was (a) reflexly moved, (b) voluntarily moved through the same trajectory at the same rate, (c) passively moved, (d) still, and (e) vibrated while still. Less adaptation occurred as the amount of proprioceptive information about limb position was decreased. The adaptation elicited by voluntary movements of the forearm and by reflex movements did not differ significantly. It is concluded that corollary-discharge signals may not be crucial in adaptation to visual rearrangement; a more important factor appears to be discordance between proprioceptive and visual information.     

Market forces,negotiator frames and transaction outcomes

Although implicit framing differences have been advanced as an explanation of the buyers advantage, two necessary preconditions must be met to sustain this model: a demonstration that negatively-framed negotiators are advantaged in negotiations and that buyer role labels invoke a negative frame. A modification of Neale, Northcraft, Magliozzi and Bazerman s (1986) simulation created a role-neutral setting in which positively-framed negotiators bargained against negatively-framed negotiators, thus testing the first of these preconditions. Experiment 1 found no differences in the outcomes of positively- and negatively-framed negotiators, a finding that could be attributed to relatively low market competitiveness. A second experiment, by creating power imbalanced negotiation markets, sought to increase market distributiveness and strengthen framing effects. Results showed that both high power and negatively-framed negotiators were significantly advantaged, providing conditional support for the implicit framing model, However unlike role, frame interacted with power suggesting that the two variables are not functionally equivalent. These findings are interpreted to suggest that factors other than implicit framing differences account for the buyers advantage. More generally these results suggest that frame is responsive to situational variables and that such variables, by influencing negotiation processes, mediate the relationship between negotiator frames and negotiation outcomes.     

Source monitoring and suggestibility to misinformation: adult age‐related differences

We compared young and older adults' source monitoring performance on an explicit source identification test using the misinformation paradigm. Several age‐related differences in source memory were demonstrated: (a) older adults were more likely than were young adults to say that they saw information that was actually only suggested to them; (b) older adults were more confident in their false memories than were young adults; (c) older adults were less confident in their accurate memory for the source of information than were young adults. Together, the data suggest that older adults either lacked or failed to use helpful diagnostic source information (e.g. perceptual details or temporal information), and that their confidence in their false memories reflected an over‐weighting of semantic information. Copyright © 2002 John Wiley & Sons, Ltd.     

Timed excitatory conditioning under zero and negative contingencies

Rats (rattus norvegicus) anticipated the arrival of a food pellet unconditioned stimulus (US) even when the conditioned stimulus (CS) signaled no overall change or a substantial decrease in the overall rate of US occurrence. Pellet USs were scheduled probabilistically in the intertrial interval at either an equivalent rate (Experiment 1) or a four times higher rate (Experiments 2 and 3) than in the CS, which included one fixed-time target US. Conditioning has been said to involve learning "whether" (contingency) the CS signals a change in the US, and if so, "when" (contiguity) the US is scheduled to arrive. Our results suggest that "when" trumps "whether," challenging the received view that a positive CS-US contingency is necessary for successful conditioning.     

Busy perceivers and ineffective suppression goals: a critical role for distracter thoughts

With limited cognitive resources, suppressing thoughts can be ineffective. The detrimental effects of cognitive load on suppression have typically been attributed to increased accessibility of avoided thoughts. However, little research has examined distracter thoughts and their contribution to these effects. In three studies, participants pursued suppression goals related to social judgments (e.g., avoid negative thoughts about a target's performance) with sufficient or diminished cognitive resources. Compared to suppressors not under cognitive load, suppressors under load drew more negative social inferences when pursuing a negative suppression goal and more positive inferences under a positive suppression goal; load did not similarly disrupt a concentration goal (i.e., focus on positive thoughts). Across studies, load reduced high-quality oppositely valenced distracter thoughts, and these distracter thoughts mediated the detrimental effects of load on social inferences. The discussion focuses on mechanisms underlying the effects of load on suppression, implications, and future directions for research on ironic processes.     

Aging and goal-directed emotional attention: distraction reverses emotional biases

Previous findings reveal that older adults favor positive over negative stimuli in both memory and attention (for a review, see Mather & Carstensen, 2005). This study used eye tracking to investigate the role of cognitive control in older adults' selective visual attention. Younger and older adults viewed emotional-neutral and emotional-emotional pairs of faces and pictures while their gaze patterns were recorded under full or divided attention conditions. Replicating previous eye-tracking findings, older adults allocated less of their visual attention to negative stimuli in negative-neutral stimulus pairings in the full attention condition than younger adults did. However, as predicted by a cognitive-control-based account of the positivity effect in older adults' information processing tendencies (Mather & Knight, 2005), older adults' tendency to avoid negative stimuli was reversed in the divided attention condition. Compared with younger adults, older adults' limited attentional resources were more likely to be drawn to negative stimuli when they were distracted. These findings indicate that emotional goals can have unintended consequences when cognitive control mechanisms are not fully available.     

The role of motivation in the age-related positivity effect in autobiographical memory

Abstract— This study reveals that older adults have a positivity effect in long-term autobiographical memory and that a positivity bias can be induced in younger adults by a heightened motivation to regulate current emotional well-being. Three hundred nuns, ages 47 to 102 years, recalled personal information originally reported 14 years earlier. They did so under experimental conditions that repeatedly primed them to focus on their current emotional states or on their memory accuracy, or that provided no instructional focus (control condition). Both older control participants and participants who were focused on emotional states showed a tendency to remember the past more positively than they originally reported in 1987. In contrast, both younger control participants and participants who were focused on accuracy tended to remember the past more negatively than originally reported.