Hippocampal sequences link past, present, and future

Disrupting the reactivation of hippocampal neurons during sleep impairs memory consolidation in rats. However, the functional importance of reactivation during awake states is unknown. An experiment in which awake reactivation was disrupted suggests that this phenomenon could adaptively guide behavior by linking previous learning with the current state of the world.     

Exploring the ability to identify visual search differences when observing drivers’ eye movements

How can we improve learner drivers’ visual skills? Much research has demonstrated that learner drivers have an impoverished spread of search during driving and that this is partly due to lack of knowledge of where and when to look, rather than simply an issue of cognitive load. Several training interventions have tried to improve scanning in these drivers with limited success. We propose that exposing drivers to examples of good and bad scanning behaviour may prove to be a useful tool in training visual search. The success of this approach, however, requires drivers to be able to distinguish between examples of good and bad scanning. To this end, two studies were undertaken where video clips of simulated driving with an overlaid eye movement trace were presented to participants who had to judge whether the eye movements were that of a learner driver or a driving instructor. Overall, participants found this discrimination task very difficult. However, the findings suggested that novice and learner drivers were able to correctly classify those eye movement traces of other learner drivers better than chance. It was also demonstrated that the ability to distinguish between the eye movements of learner drivers and driving instructors improved as the number of objective differences between the two groups increased across specific scenarios (as determined by frame-by-frame analysis using a priori categories). The results suggest that, under certain situations, drivers can extract information about the appropriateness of a particular scanning strategy just by watching a video of the eye movement trace. The implications for training interventions are discussed.     

Specificity of the 21-Item Test in two elderly samples

ABSTRACT The purpose of this study was to measure the specificity of the 21-Item Test for detecting malingering in an elderly sample. The 21-Item Test was administered to 20 community-dwelling elderly individuals with means for age, education, and Short Portable Mental Status Questionnaire (SPMSQ) error scores of 76.25 years (SD?=?7.19), 14.30 years (SD?=?3.89), and 0.30 (SD?=?4.70). None of these healthy elderly participants were cognitively impaired. A second group of 53 nursing home residents had means for age, education, and SPMSQ error scores of 82.79 years (SD?=?8.56), 11.14 years (SD = 2.46), and 3.17 (SD?=?2.46). Approximately 60% of the nursing home participants had cognitive impairment based on the SPMSQ. The cut offs provided by Iverson (1998 , 21 Item Test Research Manual) for interpretation of the forced-choice component of the 21-Item Test were insensitive to age and relatively insensitive to cognitive deficits. Specificity was 100% since no elderly participant from either group scored in the range indicative of sub-optimal effort or biased responding.     

Age-Related Differences in Lay Conceptions of Well-Being and Experienced Well-Being

Conceptions of well-being are defined as a system of beliefs concerning the nature and experience of well-being and can be described generally by the degree to which four dimensions, representing (1) the experience of pleasure, (2) avoidance of negative experience, (3) selfdevelopment, and (4) contribution to others, are emphasized. A first main objective of the current study was to investigate age-related differences in younger and older adults’ conceptions of well-being. A second main objective was to address whether conceptions of well-being are differentially associated with experienced well-being in younger and older adults. Results indicated several age-related differences in conceptions of well-being, with younger adults reporting more emphasis on the experience of pleasure and self-development, older adults reporting more emphasis on avoidance of negative experience, and younger and older adults reporting similar levels of emphasis on contribution to others. Results further indicated several age-related differences in associations between the experience of pleasure and avoidance of negative experience dimensions and well-being, with these two dimensions being more strongly and positively associated with well-being in older adults. Self-development and contribution to others were found to be positively associated with well-being regardless of age.     

Effects of cage mesh on pointing: hand shapes in chimpanzees (<Emphasis Type="Italic">Pan troglodytes</Emphasis>)

It has been speculated that cage mesh exerts a shaping influence on reaching behavior by captive apes, which is then misconstrued as pointing by human observers. Although this notion is clearly falsified by the pointing of captive language-trained apes—who point in the absence of intervening cage mesh—nevertheless, the degree to which cage mesh might influence pointing hand shapes by captive great apes in other housing environments remains relatively unexplored. We examined 259 pointing gestures displayed in archival footage from over 18 h of observation by three nonlanguage-trained chimpanzees housed at a biomedical research center. We coded points in relation to how close to the boundaries of the diamond-shaped cage mesh their points were displayed. We found that points with the whole hand were significantly more likely to be displayed away from the mesh boundaries, relative to points with the index finger or other single-digit points. However, points of each hand shape were displayed at each location, demonstrating that these physical parameters do not fully account for the number of fingers extended while pointing by chimpanzees.     

Target animacy influences chimpanzee handedness

We employed a bottom-up, quantitative method to investigate great ape handedness. Our previous investigation of gorillas (Gorilla gorilla gorilla) demonstrated that contextual information influenced an individual’s handedness toward target objects. Specifically, we found a significant right-hand bias for unimanual actions directed toward inanimate target objects but not for actions directed to animate target objects (Forrester et al. in Anim Cogn 14(6):903–907, 2011). Using the identical methodological technique, we investigated the spontaneous hand actions of nine captive chimpanzees (Pan troglodytes) during naturalistic, spontaneous behavior. We assessed both the frequencies and proportions of lateralized hand actions directed toward animate and inanimate targets employing focal follow video sampling. Like the gorillas, the chimpanzees demonstrated a right-handed bias for actions directed toward inanimate targets, but not toward animate targets. This pattern was evident at the group level and for the majority of subjects at the individual level. We postulate that a right-hand bias for only inanimate targets reflects the left hemisphere’s dominant neural processing capabilities for objects that have functional properties (inanimate objects). We further speculate that a population-level right-hand bias is not a human-unique characteristic, but one that was inherited from a common human-ape ancestor.     

But I can’t pass that far! The influence of motor skill on decision making

Objectives

The influence of motor skill on perceptual-cognitive and perceptual-motor decision making has been theorised but not verified empirically.

Method

Expert (n = 19), developmental (n = 20), and lesser-skilled netballers (n = 19) completed tests designed to evaluate three different components of domain-specific expertise: (i) motor skill-execution; (ii) perceptual-cognitive decision making; and (iii) perceptual-motor decision making.

Results

Each of the three measures was found to improve commensurate with domain-specific skill. Decisions requiring movements (perceptual-motor) elicited more accurate decision making than simple verbal responses (perceptual-cognitive), irrespective of participant skill. Although motor skill was found to be related to the successful execution of a most appropriate movement in a game situation, it was not found to limit the nature of the decision made by participants. No evidence was found to support the supposition that lesser-skilled participants bias their perceptual-cognitive decisions towards ones supported by their motor ability.

Conclusions

Results fail to comprehensively support the contemporary models for the development of perceptual-cognitive and perceptual-motor skill in sport.     

A 15-year longitudinal test of the theory of planned behaviour to predict physical activity in a randomized national sample of Canadian adults

BackgroundThere have been very limited long-term prospective studies examining social-cognitive models in the PA domain with large, representative population samples.ObjectiveThe primary objective was to examine the Theory of Planned Behaviour's (TPB) ability to explain PA behaviour in a randomly selected national sample of Canadian adults over a 15-year period. A secondary objective was to test the moderating effects of gender on TPB.DesignThe study employed a longitudinal design.MethodsA cohort of 1427 randomly-selected adults reported TPB constructs and PA behaviour in 1988, and again in 2003. Structural equation modelling techniques were employed to test TPB.ResultsThe full model including both 1988 and 2003 TPB measures accounted for 29% and 21% of the variance in intention, and 9% and 22% of the variance in PA in 1988 and 2003, respectively. Gender moderated aspects of the TPB in the full model. The core predictive model (1988 TPB constructs predicting 2003 PA behaviour) explained 13% of the variance in 2003 PA behaviour.ConclusionsThe TPB's long-term ability to predict PA behaviour is modest.     

What have you done for me lately? Friendship-selection in the shadow of the Dark Triad traits

The current studies examined how the Dark Triad personality traits (i.e., Machiavellianism, narcissism, and psychopathy) facilitate the strategic structuring of an individual's social environment in terms of same- and opposite-sex friends. In one study using normative questions (N = 267) and another using a budget-allocation task (N = 114), we found that the Dark Triad traits were associated with choosing friends for strategic purposes and to create a volatile environment. Narcissistic individuals reported relatively more reasons to form friendships, such as shared interests, makes me feel good, and intelligence. Women high in narcissism chose same-sex friends who were attractive and women high on Machiavellianism chose same-sex friends who have social status. Men high on psychopathy devalued traits associated with good social relationships in favor of friends who could facilitate their mating efforts and to offset risks incurred in their life history strategy. Results are discussed using the selection-manipulation-evocation framework for explaining how personality traits interact with social environments and integrated with findings from evolutionary biology.