Longitudinal attentional engagement rescues mice from age-related cognitive declines and cognitive inflexibility

Learning, attentional, and perseverative deficits are characteristic of cognitive aging. In this study, genetically diverse CD-1 mice underwent longitudinal training in a task asserted to tax working memory capacity and its dependence on selective attention. Beginning at 3 mo of age, animals were trained for 12 d to perform in a dual radial-arm maze task that required the mice to remember and operate on two sets of overlapping guidance (spatial) cues. As previously reported, this training resulted in an immediate (at 4 mo of age) improvement in the animals' aggregate performance across a battery of five learning tasks. Subsequently, these animals received an additional 3 d of working memory training at 3-wk intervals for 15 mo (totaling 66 training sessions), and at 18 mo of age were assessed on a selective attention task, a second set of learning tasks, and variations of those tasks that required the animals to modify the previously learned response. Both attentional and learning abilities (on passive avoidance, active avoidance, and reinforced alternation tasks) were impaired in aged animals that had not received working memory training. Likewise, these aged animals exhibited consistent deficits when required to modify a previously instantiated learned response (in reinforced alternation, active avoidance, and spatial water maze). In contrast, these attentional, learning, and perseverative deficits were attenuated in aged animals that had undergone lifelong working memory exercise. These results suggest that general impairments of learning, attention, and cognitive flexibility may be mitigated by a cognitive exercise regimen that requires chronic attentional engagement.     

Effects of pharmacological manipulations of NMDA-receptors on deliberation in the Multiple-T task

Both humans and non-human animals have the ability to navigate and make decisions within complex environments. This ability is largely dependent upon learning and memory processes, many of which are known to depend on NMDA-sensitive receptors. When humans come to difficult decisions they often pause to deliberate over their choices. Similarly, rats pause at difficult choice points. This behavior, known as vicarious trial and error (VTE), is hippocampally dependent and entails neurophysiological representations of expectations of future outcomes in hippocampus and downstream structures. In order to determine the dependence of VTE behaviors on NMDA-sensitive receptors, we tested rats on a Multiple-T choice task with a reward-delivery reversal known to elicit VTE. Rats under the influence of NMDA-receptor antagonists (CPP) showed a significant reduction in VTE, particularly at the reward reversal, implying a role for NMDA-sensitive receptors in the generation of vicarious trial and error behaviors.     

The role of overt attention in emotion-modulated memory

The presence of emotional stimuli results in a central/peripheral tradeoff effect in memory: memory for central details is enhanced at the cost of peripheral items. It has been assumed that emotion-modulated differences in memory are the result of differences in attention, but this has not been tested directly. The present experiment used eye movement monitoring as an index of overt attention allocation and mediation analysis to determine whether differences in attention were related to subsequent memory. Participants viewed negative and neutral scenes surrounded by three neutral objects and were then given a recognition memory test. The results revealed evidence in support of a central/peripheral tradeoff in both attention and memory. However, contrary with previous assumptions, whereas attention partially mediated emotion-enhanced memory for central pictures, it did not explain the entire relationship. Further, although centrally presented emotional stimuli led to decreased number of eye fixations toward the periphery, these differences in viewing did not contribute to emotion-impaired memory for specific details pertaining to the periphery. These findings suggest that the differential influence of negative emotion on central versus peripheral memory may result from other cognitive influences in addition to overt visual attention or on postencoding processes.     

Emotion enhanced retention of cognitive skill learning

Ample evidence suggests that emotional arousal enhances declarative/episodic memory. By contrast, there is little evidence that emotional enhancement of memory (EEM) extends to procedural skill based memory. We examined remote EEM (1.5-month delay) for cognitive skill learning using the weather prediction (WP) probabilistic classification task. Participants viewed interleaved emotionally arousing or neutral pictures during WP acquisition. Arousal retarded initial WP acquisition. While participants in the neutral condition showed substantial forgetting of WP learning across the 1.5-month delay interval, the arousal condition showed no evidence of forgetting across the same time period. Thus, arousal during encoding determined the mnemonic fate of cognitive skill learning. Emotional enhancement of WP retention was independent of verbally stated knowledge of WP learning and EEM for the picture contexts in which learning took place. These results reveal a novel demonstration of EEM for cognitive skill learning, and suggest that emotional arousal may in parallel enhance the neural systems that support procedural learning and its declarative context.     

Why do we listen to music? A uses and gratifications analysis

Four 'uses and gratifications' studies investigated peoples' reasons for listening to music (Study 1); and whether these reasons differ significantly from those associated with other leisure activities (Study 2). In Study 3, an open-ended, qualitative research design was used to investigate why people listen to music. In Study 4, a cross-sectional design was used to investigate the possibility that people of different ages might listen to music for different reasons. Findings showed that there are a number of reasons why participants listen to music, comparison of which indicated that participants listen to music primarily to manage/regulate their moods. Comparison with other leisure activities indicated that for the most part, listening to music was rated better than other leisure activities at serving an individual's different needs. This versatility may explain why music is so important to people. Evidence was also found to suggest that the reasons for listening to music may change as people grow older.     

Hot or cold: is communicating anger or threats more effective in negotiation?

Is communicating anger or threats more effective in eliciting concessions in negotiation? Recent research has emphasized the effectiveness of anger communication, an emotional strategy. In this article, we argue that anger communication conveys an implied threat, and we document that issuing threats is a more effective negotiation strategy than communicating anger. In 3 computer-mediated negotiation experiments, participants received either angry or threatening messages from a simulated counterpart. Experiment 1 showed that perceptions of threat mediated the effect of anger (vs. a control) on concessions. Experiment 2 showed that (a) threat communication elicited greater concessions than anger communication and (b) poise (being confident and in control of one's own feelings and decisions) ascribed to the counterpart mediated the positive effect of threat compared to anger on concessions. Experiment 3 replicated this positive effect of threat over anger when recipients had an attractive alternative to a negotiated agreement. These findings qualify previous research on anger communication in negotiation. Implications for the understanding of emotion and negotiation are discussed.     

Exemplar models as a mechanism for performing Bayesian inference

Probabilistic models have recently received much attention as accounts of human cognition. However, most research in which probabilistic models have been used has been focused on formulating the abstract problems behind cognitive tasks and their optimal solutions, rather than on mechanisms that could implement these solutions. Exemplar models are a successful class of psychological process models in which an inventory of stored examples is used to solve problems such as identification, categorization, and function learning. We show that exemplar models can be used to perform a sophisticated form of Monte Carlo approximation known as importance sampling and thus provide a way to perform approximate Bayesian inference. Simulations of Bayesian inference in speech perception, generalization along a single dimension, making predictions about everyday events, concept learning, and reconstruction from memory show that exemplar models can often account for human performance with only a few exemplars, for both simple and relatively complex prior distributions. These results suggest that exemplar models provide a possible mechanism for implementing at least some forms of Bayesian inference.     

Central cannabinoid receptors modulate acquisition of eyeblink conditioning

Delay eyeblink conditioning is established by paired presentations of a conditioned stimulus (CS) such as a tone or light, and an unconditioned stimulus (US) that elicits the blink reflex. Conditioned stimulus information is projected from the basilar pontine nuclei to the cerebellar interpositus nucleus and cortex. The cerebellar cortex, particularly the molecular layer, contains a high density of cannabinoid receptors (CB1R). The CB1Rs are located on the axon terminals of parallel fibers, stellate cells, and basket cells where they inhibit neurotransmitter release. The present study examined the effects of a CB1R agonist WIN55,212-2 and antagonist SR141716A on the acquisition of delay eyeblink conditioning in rats. Rats were given subcutaneous administration of 1, 2, or 3 mg/kg of WIN55,212-2 or 1, 3, or 5 mg/kg of SR141716A before each day of acquisition training (10 sessions). Dose-dependent impairments in acquisition were found for WIN55,212-2 and SR141716A, with no effects on spontaneous or nonassociative blinking. However, the magnitude of impairment was greater for WIN55,212-2 than SR141716A. Dose-dependent impairments in conditioned blink response (CR) amplitude and timing were found with WIN55,212-2 but not with SR141716A. The findings support the hypothesis that CB1Rs in the cerebellar cortex play an important role in plasticity mechanisms underlying eyeblink conditioning.     

Humanizing Personhood

This paper explores the debate between personists, who argue that the concept of a person if of central importance for moral thought, and personists, who argue that the concept of a human being is of greater moral significance. On the one hand, it argues that normative naturalism, the most ambitious defense of the humanist position, fails to identify moral standards with standards of human behavior and thereby fails to undermine the moral significance of personhood. At the same time, it contends that a more focused attention on the morally relevant features of human life may indeed play a crucial role in enhancing our moral understanding.     

Personal, Medical, and Healthcare Utilization Among Homeless Veterans Served by Metropolitan and Nonmetropolitan Veteran Facilities

This study assessed differences in personal, medical, and health care utilization characteristics of homeless veterans living in metropolitan versus nonmetropolitan environments. Data were obtained from a Veterans Health Administration (VHA) network sample of homeless veterans. Chi-square tests were used to assess differences in demographics, military history, living situation, medical history, employment status, and health care utilization. Moderator analyses determined whether predictors of health care utilization varied by metropolitan status. Of 3,595 respondents, 60% were residing in metropolitan areas. Age, sex, and marital status were similar between metropolitan and nonmetropolitan homeless. Metropolitan homeless were less likely to receive public financial support or to be employed, to have at least one medical problem, one psychiatric problem, or current alcohol dependency, but more likely to be homeless longer. Of the 52% of the sample who used VHA care in the last 6 months, 53% were metropolitan versus 49% nonmetropolitan (p = .01). Metropolitan status predicted at least one VHA visit within the prior 6 months (OR:1.3, CI:1.1, 1.6). Significant differences occur in the personal, medical, and health care utilization characteristics of homeless veterans in metropolitan versus nonmetropolitan areas.