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.     

Meaning and the External World

Realism, defined as a justified belief in the existence of the external world, is jeopardized by ‘meaning rationalism,’ the classic theory of meaning that sees the extension of words as a function of the intensions of individual speakers, with no way to ensure that these intensions actually correspond to anything in the external world. To defend realism, Ruth Millikan (1984, 1989a, b, 1993, 2004, 2005) offers a biological theory of meaning called ‘teleosemantics’ in which words, without requiring any contribution from the speaker’s intensions, are supposedly matched directly with their extensions by external norms. But even if one granted as a theoretical possibility that word meaning might possibly be stabilized through an external process, nonetheless, realists who wish to appeal to teleosemantics for a semantic proof of the external world must be capable of identifying these external norms, something that Millikan describes as highly fallible. Furthermore, because they can be aware of these norms only as these are internally represented, it would also be necessary for realists to verify that these internal representations accurately reflect the norms as they occur in the external world. But given that this is virtually the same stumbling block to realism found in meaning rationalism, it is concluded that teleosemantics is not likely to restore faith in this worldview.

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The formation of a generalized categorization repertoire: effect of training with multiple domains,samples, and comparisons

The present experiment explored the effects of three variables on the spontaneous categorization of stimuli in perceptually distinct and novel domains. Each of six stimulus domains was created by morphing two images that were the domain endpoints. The endpoints of the domains were male and female faces, two abstract drawings, a car and a truck, two banded-elevation satellite land images, a tree and a cat, and two false-color satellite images. The stimulus variants at each end of a domain defined two potential perceptual classes. Training was conducted in a matching-to-sample format and used stimuli from one or two domains, one or three variants per class as samples, and one or three variants per class as comparisons. The spontaneous categorization of stimuli in the untrained stimulus domains showed the emergence of a generalized categorization repertoire. The proportion of spontaneously categorized stimuli in the new domains was positively related to the number of domains and samples used in training, and was inversely related to the number of comparisons used in training. Differential reaction times demonstrated the discriminability of the stimuli in the emergent classes. This study is among the first to provide an empirical basis for a behavior-analytic model of the development of generalized categorization repertoires in natural settings.     

The Infrequency-Posttraumatic Stress Disorder scale (Fptsd) for the MMPI-2: development and initial validation with veterans presenting with combat-related PTSD

Researchers have identified difficulties associated with the use of traditional Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) validity scales with survivors of traumatic events. A new scale, the Infrequency-Posttraumatic Stress Disorder scale (Fptsd), was created from MMPI-2 items that were infrequently endorsed by 940 male combat veterans presenting for treatment at the posttraumatic stress disorder (PTSD) clinics of 2 Veterans Affairs Medical Centers. A variety of statistical methods were implemented that preliminarily established Fptsd's validity with a validation sample of 323 additional PTSD-diagnosed combat veterans. Results indicate that, relative to previously established validity and overreporting scales (F, Fb, and Fp), Fptsd was significantly less related to psychopathology and distress and better at discriminating simulated from genuinely reported PTSD. Clinical implications are discussed concerning the use of Fptsd to assess disability-seeking veterans suspected of overreporting PTSD symptoms.     

It depends on how you look at it: Scanpath comparison in multiple dimensions with MultiMatch, a vector-based approach

Eye movement sequences??or scanpaths??vary depending on the stimulus characteristics and the task (Foulsham & Underwood Journal of Vision, 8(2), 6:1?C17, 2008; Land, Mennie, & Rusted, Perception, 28, 1311?C1328, 1999). Common methods for comparing scanpaths, however, are limited in their ability to capture both the spatial and temporal properties of which a scanpath consists. Here, we validated a new method for scanpath comparison based on geometric vectors, which compares scanpaths over multiple dimensions while retaining positional and sequential information (Jarodzka, Holmqvist, & Nystr?m, Symposium on Eye-Tracking Research and Applications (pp. 211?C218), 2010). ??MultiMatch?? was tested in two experiments and pitted against ScanMatch (Cristino, Math?t, Theeuwes, & Gilchrist, Behavior Research Methods, 42, 692?C700, 2010), the most comprehensive adaptation of the popular Levenshtein method. In Experiment 1, we used synthetic data, demonstrating the greater sensitivity of MultiMatch to variations in spatial position. In Experiment 2, real eye movement recordings were taken from participants viewing sequences of dots, designed to elicit scanpath pairs with commonalities known to be problematic for algorithms (e.g., when one scanpath is shifted in locus or when fixations fall on either side of an AOI boundary). The results illustrate the advantages of a multidimensional approach, revealing how two scanpaths differ. For instance, if one scanpath is the reverse copy of another, the difference is in the direction but not the positions of fixations; or if a scanpath is scaled down, the difference is in the length of the saccadic vectors but not in the overall shape. As well as having enormous potential for any task in which consistency in eye movements is important (e.g., learning), MultiMatch is particularly relevant for ??eye movements to nothing?? in mental imagery and embodiment-of-cognition research, where satisfactory scanpath comparison algorithms are lacking.     

Is Workplace Harassment Hazardous to Your Health?

We examined cross-sectional and lagged effects of sexual harassment (SH) and generalized workplace harassment (GWH) on incidence of self-reported illness, injury, or assault in a sample of over 1,500 university employees. SH and GWH, but not other job stressors, were related to increased odds of illness, injury, or assault. This was true when SH, GWH, and illness, injury, or assault were measured at the same time point, as well as when SH and GWH were measured in year prior to illness, injury, or assault.The data presented here are part of an ongoing longitudinal study of workplace harassment conducted at the Department of Psychiatry of the University of Illinois at Chicago. This research was supported by the National Institute on Alcohol Abuse and Alcoholism (grants AA09989 and AA13332). Portions of this paper were presented at the annual meeting of the Society for Industrial and Organizational Psychology, April 2004, Chicago, Illinois. The data were collected by the Survey Research Laboratory at the University of Illinois at Chicago.     

Relations Between Coping and Positive and Negative Outcomes in Carers of Persons with Multiple Sclerosis (MS)

This study examined relations between stress and coping predictors and negative and positive outcomes in MS caregiving. A total of 222 carers and their care-recipients completed questionnaires at Time 1 and three months later, Time 2 (n = 155). Predictors included care-recipient characteristics (age, time since diagnosis, course and life satisfaction), and Times 1 and 2 carer problems, stress appraisal and coping. Dependent variables were Time 2 negative (anxiety, depression) and positive outcomes (life satisfaction, positive affect, benefits). Regressions indicated that, overall, the hypothesised direct effects of stress appraisal and coping strategies on positive and negative outcomes were supported. The hypothesised stress-buffering effects of positive reframing coping were also supported. All but one of the coping strategies were related to both positive and negative outcomes; specifically, practical assistance coping emerged as a unique predictor of distress. Of the model predictors, care-recipient life satisfaction emerged as the strongest and most consistent predictor of both positive and negative outcomes except benefit finding. Findings support the role of care-recipient characteristics and the carers appraisal and coping processes in shaping both positive and negative outcomes. The guiding framework and findings have the potential to inform interventions designed to promote well-being in carers.     

Subjective and reinforcing effects of smoking during negative mood induction

Two notions strongly held by many smokers are that negative mood increases smoking behavior and that this increase is due to the ability of smoking to alleviate negative affect. This study used a modified mood induction procedure to examine both the impact of smoking on induced mood, as well as the effect of induced mood on actual smoking behavior. Forty-eight smokers were randomly assigned to a smoking or a water-drinking comparison group. Each participant attended 3 sessions during which 1 of 3 mood states (positive, negative, or neutral) was induced. Contrary to expectation, smoking did not attenuate negative affect. However, negative mood induction subsequently quickened latency to smoke and increased number of puffs consumed ad lib.