Induction and activity-dependent reversal of persistent LTP and LTD in lateral perforant path synapses in vivo

The reversibility of long-term potentiation (LTP) and heterosynaptic long-term depression (LTD) lasting weeks was examined in the lateral perforant path of freely moving adult Sprague-Dawley rats. LTP lasting weeks was rapidly reversed within minutes by high-frequency heterosynaptic stimulation of the medial perforant path, in an N-methyl-D-aspartate receptor-dependent manner. LTP reversal also occurred, albeit more slowly and to a lesser extent, when animals were given 1-3 weeks of overnight exposure to an enriched environment (EE). LTD likewise was reversed upon repeated EE exposure. A covert similarity between the degrees of LTP and LTD reversal was revealed when the small potentiation effect of EE treatment by itself on lateral path responses was taken into account. Despite its ability to reverse previously acquired synaptic plasticity, two weeks of EE treatment had no effect on animals' retention of the platform location in a spatial watermaze task, although it did facilitate new learning. These data are in agreement with the hypothesis that hippocampal synapses retain the capacity for rapid synaptic change even when otherwise relatively stable plasticity has previously been induced. Slow reversal of such plasticity did not correlate with a loss of memory retention, possibly because either slow changes permit reorganization of representations such that both old and new information can be accommodated, or else the new information is synaptically represented in orthogonal fashion to the old information.     

On what it means to know someone: a matter of pragmatics

Two studies provide support for W. B. Swann's (1984) argument that perceivers achieve substantial pragmatic accuracy--accuracy that facilitates the achievement of relationship-specific interaction goals--in their social relationships. Study 1 assessed the extent to which group members reached consensus regarding the behavior of a member in familiar (as compared with unfamiliar) contexts and found that groups do indeed achieve this form of pragmatic accuracy. Study 2 assessed the degree of insight romantic partners had into the self-views of their partners on relationship-relevant (as compared with less relevant) traits and found that couples do indeed achieve this form of pragmatic accuracy. Furthermore, pragmatic accuracy was uniquely associated with relationship harmony. Implications for a functional approach to person perception are discussed.     

Image of aging scale

The development of the Image of Aging Scale is described. It ineludes positive and negative images of elders within nine domains. The scale showed good 1-wk. test-retest reliability, internal consistency, and convergent validity.     

Educating Genetic Counselors in Australia: Developing an International Perspective

The demand for genetic counseling services is increasing worldwide. This paper highlights the Australian experience of genetic counselor education and the history of the profession. The relevance of local factors, including the healthcare system, the education system and the small population in the evolution of the 1-year training programs are considered as an alternative model for emerging programs. The development of the education and training processes compared to that of other countries namely the United States of America (USA), the United Kingdom (UK) and Canada is discussed. The importance of international collaborations between the programs, to facilitate academic discussion and possible curriculum innovations, and to maintain professional understanding between genetic counselors is emphasized. Core genetic counseling competencies have been published for the UK and USA and an Australian set is proposed. In conclusion future directions are considered, including international issues around genetic counseling certification, reciprocity, and the potential for an Australian role in training genetic counselors in South East Asia.     

Occupational stress and burnout amongst staff working with people with an intellectual disability

The Occupational Stress Inventory (Osipow & Spokane, 1987) and the Maslach Burnout Inventory (Maslach, 1982) were used to assess the levels of occupational stress and burnout amongst staff providing services to people with an intellectual disability both in an institutional and community settings. Data were analyzed to determine the effects of direct client contact, staff mental health, and working environment (institution vs. community). While levels of burnout and occupational stress were not high overall, staff working in an institutional setting scores more highly.     

Discriminative vocal conditioning in rhesus monkeys: Evidence for volitional control?

Both emotional and volitional systems are invoked in explaining the control of human vocalizations, but vocal behavior of nonhuman primates is often believed to be totally under emotional control. Monkeys' poor performance on conditioning tasks, especially discriminative conditioning of vocalization (DCV), has been cited as evidence against volitional control. In Experiment 1, rhesus monkeys failed a DCV task in which food was given for vocalizations emitted during an arbitrary visual stimulus, but in Experiment 2, monkeys showed clear discriminative performance when an otherwise comparable shock-avoidance DCV procedure was used. This evidence that monkeys possess some degree of volitional control has implications for the relation between animal vocalizations and the origin of human speech.     

A plausible role of imagination in pretend play,counterfactual reasoning,and executive functions

A notable observation is the similarities in the cognitive processes of pretend play (PP) and counterfactual reasoning (CFR) as both involve thinking about alternatives to reality. It is argued by Weisberg and Gopnik (Cogn. Sci., 37, 2013, 1368) that alternative thinking in PP and CFR is underpinned by an imaginary representational capacity but few studies have empirically investigated this link. We use a variable latent modelling approach to test a hypothetical model of the structural relationship of PP and CFR predicting that if PP and CFR are cognitively similar; they should have similar patterns of associations with Executive Functions (EFs). Data were collected on PP, CFR, EFs and Language from 189 children (M = 4.8 years, males = 101, females = 88). Confirmatory factor analyses showed that measures of PP and CFR loaded onto single latent constructs and were significantly correlated (r = .51, p = .001) with each other. Hierarchical multiple regression analyses revealed that EF accounted for unique significant variance in both PP (β = 21) and CFR (β = 22). The results of the structural equation modelling revealed that the data were a good fit for the hypothetical model. We discuss the plausible role of a general underlying imaginative representational capacity to explain similarities in the cognitive mechanisms of different states of alternative thinking like PP and CFR.     

Re-examination of the role of within-compound associations in the retrospective revaluation of causal judgements

We investigated blocking and retrospective revaluation of causal judgements using a scenario in which food cues acted as potential causes of an allergic reaction as the outcome. In the blocking contingency,the treatment cues were either paired or unpaired with the outcome prior to a second stage in which sequential compounds of treatment and target cues were paired with the outcome. The order of this compound and treatment training was reversed in retrospective revaluation contingencies. When the interstimulus interval between the treatment and target cues was unfilled on compound trials (Experiments 1 and 3), both blocking and retrospective revaluation were observed in that the target cue trained in compound with the paired treatment cue attracted lower causal ratings than the target cue trained in compound with the unpaired treatment cue. By contrast, performing a mental arithmetic task using numerals presented during the interstimulus interval had no effect on the magnitude of blocking but rendered retrospective revaluation unreliable (Experiments 2 and 3). These results provide further support for accounts of revaluation based upon within-compound associations.