Choice With Initial and Terminal Link Reinforcement: An Alternative Self-Control Paradigm.

Self-control is demonstrated when a less desirable immediate outcome is chosen to ensure a substantially better future. In a novel animal analogue of this situation, primary reinforcement was delivered in both the initial and terminal links of a concurrent chain schedule. Rats made initial link choices between equal amounts of ethanol-free or ethanol-containing milk. Choosing the ethanol-free reinforcer resulted in delivery of the larger terminal link reinforcer and was thus analogous to self-control. Self-control decreased as the delay between initial and terminal links increased. The results have implications for human choice situations where decisions are made between two immediately available reinforcement alternatives each associated with a different delayed outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Imaging of hippocampal and neocortical neural activity following intravenous cocaine administration in freely behaving cats

We examined spatial-temporal patterns of neural activity, as inferred from 700 nm light reflectance, from the dorsal hippocampus and surrounding neocortex in seven freely behaving cats following 1.5, 2.5, 3.5 and 5.0 mg/kg intravenous cocaine administration. Images were acquired using a new technique which gathered reflected light from cortical and subcortical structures. Cardiac and respiratory patterning, collected simultaneously with optical images, revealed increased rates and diminished variation after intravenous cocaine administration. Cocaine increased reflectance correlates of hippocampal neural activity in a dose-dependent fashion over a 120 min period, with a lengthening time-to-peak effect (22-76 min). The largest dose resulted in an initial decrease, followed by the greatest enhancement in neuronal activity. Correlates of neural activation in the neocortex displayed an inverse dose-response curve to that found in the hippocampus; the time-to-peak effect was shorter (6-43 min) and the maximal change was reduced. Regional patches and bands of activation occurred during the period of the cocaine response, and were more pronounced in the hippocampus than the neocortex. Procaine, administered in a similar dose, slightly increased neural activity for 10 min in both the hippocampus and neocortex, and elicited a small increase in respiration. Cocaine induces a pronounced enhancement of neural activation in the neocortex and dorsal hippocampus; the time course of activation in the hippocampus parallels an increased respiratory pattern and outlasts the neocortical response. We speculate that hippocampal activation may be related to the profound respiratory acceleration found in response to cocaine.     

Perceived equity and intimacy in marriage

The extent to which perceived inequity is related to perceived marital intimacy was examined. Sixty-six couples married five years or less were randomly selected from marriage license records in a western rural community. Equity/inequity was assessed using the Walster global measure of equity. Levels of overall intimacy, conflict resolution, affection, cohesion, sexuality, identity, compatibility, autonomy, and expressiveness were measured using the Waring Intimacy Questionnaire (WIQ). Inequity was associated with lower levels of overall intimacy, compatibility, identity, and expressiveness among the wives. Among the husbands, inequity was not associated with any types of intimacy. When comparing husbands in inequitable relationships to wives in inequitable relationships, the wives reported lower scores for only one kind of intimacy--identity. Explanations and implications for marriage therapy are discussed.     

Forgetting in rats following medial septum or mammillary body damage.

Examined the effects of medial septal (MS) and mammillary body (MB) radio-frequency lesions in an automated delayed-matching-to-sample (DMTS) procedure using lever-position stimuli and rats. Memory performance pre- and postsurgery was assessed with a negative exponential decay function fitted to bias-free measures of recognition. Part 1 showed that MS, but not MB or sham-control surgery, impaired DMTS performance. This impairment in the MS group was best characterized as an increase in the rate of forgetting. Part 2 examined the interaction between MS and MB lesion effects and proactive interference arising from responses made on the previous DMTS trial. The results indicated that proactive interference effects were similar for all groups. These results provide further support for the critical role of the MS region in memory function but indicate that damage to this brain region does not disrupt memory function through a heightened sensitivity to proactive interference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The flagship is dropping behind the fleet [UK telecommunicationindustry]

Following privatisation in 1984, BT was mainly preoccupied with customer service, operating costs and business exploitation. BT, its competitors and the industry regulators now have to address major new network issues. Their success in meeting the challenges of the new technologies will have a major impact on the future of UK telecommunications equipment manufacturers. The author takes a hard look at the facts. He argues that duplicating local telecommunications plant is a mistake and should stop; price cap regulation produces the wrong result; and an authoritative engineering agency is needed to co-ordinate technology nationally     

Environmental Hazard Analysis - a Variant of Preliminary Hazard Analysis for Autonomous Mobile Robots

Robot manufacturers will be required to demonstrate objectively that all reasonably foreseeable hazards have been identified in any robotic product design that is to be marketed commercially. This is problematic for autonomous mobile robots because conventional methods, which have been developed for automatic systems do not assist safety analysts in identifying non-mission interactions with environmental features that are not directly associated with the robot’s design mission, and which may comprise the majority of the required tasks of autonomous robots. In this paper we develop a new variant of preliminary hazard analysis that is explicitly aimed at identifying non-mission interactions by means of new sets of guidewords not normally found in existing variants. We develop the required features of the method and describe its application to several small trials conducted at Bristol Robotics Laboratory in the 2011–2012 period.