The unity and diversity of executive functions and their contributions to complex "Frontal Lobe" tasks: a latent variable analysis

This individual differences study examined the separability of three often postulated executive functions-mental set shifting ("Shifting"), information updating and monitoring ("Updating"), and inhibition of prepotent responses ("Inhibition")-and their roles in complex "frontal lobe" or "executive" tasks. One hundred thirty-seven college students performed a set of relatively simple experimental tasks that are considered to predominantly tap each target executive function as well as a set of frequently used executive tasks: the Wisconsin Card Sorting Test (WCST), Tower of Hanoi (TOH), random number generation (RNG), operation span, and dual tasking. Confirmatory factor analysis indicated that the three target executive functions are moderately correlated with one another, but are clearly separable. Moreover, structural equation modeling suggested that the three functions contribute differentially to performance on complex executive tasks. Specifically, WCST performance was related most strongly to Shifting, TOH to Inhibition, RNG to Inhibition and Updating, and operation span to Updating. Dual task performance was not related to any of the three target functions. These results suggest that it is important to recognize both the unity and diversity of executive functions and that latent variable analysis is a useful approach to studying the organization and roles of executive functions.     

Modern hermeneutics and psychoanalysis

Contemporary hermeneutics tries to integrate our unique, local sense of things with overarching nature, often by celebrating the concrete phenomenology of the moment at the expense of scientific abstractions. But abstractions are unavoidable. Hermeneuticists point out that we are constantly making new abstractions. But the more optional and variable views, which we call subjective, depend on the old, reliable abstractions, such as time, space, substance, and causality, that constitute our fixed reality. Hermeneutics usefully challenges psychoanalysis to justify its way of slicing up the mind and treatment process.     

Rapid word identification in pure alexia is lexical but not semantic

Following the notion that patients with pure alexia have access to two distinct reading strategies-letter-by-letter reading and semantic reading-a training program was devised to facilitate reading via semantics in a patient with pure alexia. Training utilized brief stimulus presentations and required category judgments rather than explicit word identification. The training was successful for trained words, but generalized poorly to untrained words. Additional studies involving oral reading of nouns and of functors also resulted in improved reading of trained words. Pseudowords could not be trained to criterion. The results suggest that improved reading can be achieved in pure alexia by pairing rapidly presented words with feedback. Focusing on semantic processing is not essential to this process. It is proposed that the training strengthens connections between the output of visual processing and preexisting orthographic representations.     

Differential roles for visuospatial and verbal working memory in situation model construction

Two experiments investigated the processing of the spatial and causal dimensions of situation models. In Experiment 1, participants read texts varying in spatial and causal demands while responding to on-line spatial and causal probes. Experiment 2 used the same design, but used texts that more tightly integrated spatial and causal information. In both experiments, spatially oriented dependent measures were generally influenced by spatial, but not causal, demands, whereas causally oriented measures were influenced by causal, but not spatial, demands. In addition, spatially oriented dependent measures were generally correlated with a measure of spatial working memory capacity, whereas causally oriented measures were correlated with a measure of verbal working memory capacity. These results indicate that spatial and causal dimensions of situation models are maintained and elaborated independently in different working memory subsystems.     

The effect of implementation intentions on transfer of training

Two experiments investigated the effect of forming implementation intentions on transfer of training in two training programs. In the first experiment (N = 37), trainees who formed implementation intentions implemented active listening skills sooner, and to a greater degree, than those in the control group. In the second experiment (n = 28), conducted in the field, trainees who formed implementation intentions received a higher performance score for implementing the trained behavior compared with those in the control condition. Results from both experiments provide empirical evidence suggesting that forming implementation intentions at the end of a training program increases the likelihood of using the newly acquired skills.     

DECIDE: a Decision Support Tool to Facilitate Parents’ Choices Regarding Genome-Wide Sequencing

We describe the rationale, development, and usability testing for an integrated e-learning tool and decision aid for parents facing decisions about genome-wide sequencing (GWS) for their children with a suspected genetic condition. The online tool, DECIDE, is designed to provide decision-support and to promote high quality decisions about undergoing GWS with or without return of optional incidental finding results. DECIDE works by integrating educational material with decision aids. Users may tailor their learning by controlling both the amount of information and its format – text and diagrams and/or short videos. The decision aid guides users to weigh the importance of various relevant factors in their own lives and circumstances. After considering the pros and cons of GWS and return of incidental findings, DECIDE summarizes the user’s responses and apparent preferred choices. In a usability study of 16 parents who had already chosen GWS after conventional genetic counselling, all participants found DECIDE to be helpful. Many would have been satisfied to use it alone to guide their GWS decisions, but most would prefer to have the option of consulting a health care professional as well to aid their decision. Further testing is necessary to establish the effectiveness of using DECIDE as an adjunct to or instead of conventional pre-test genetic counselling for clinical genome-wide sequencing.     

I owe you: age-related similarities and differences in associative memory for gains and losses

Older adults often experience associative memory impairments but can sometimes remember important information. The current experiments investigate potential age-related similarities and differences associate memory for gains and losses. Younger and older participants were presented with faces and associated dollar amounts, which indicated how much money the person “owed” the participant, and were later given a cued recall test for the dollar amount. Experiment 1 examined face-dollar amount pairs while Experiment 2 included negative dollar amounts to examine both gains and losses. While younger adults recalled more information relative to older adults, both groups were more accurate in recalling the correct value associated with high-value faces compared to lower-value faces and remembered gist-information about the values. However, negative values (losses) did not have a strong impact on recall among older adults versus younger adults, illustrating important associative memory differences between younger and older adults.     

The Behavioral and Pharmacological Actions of NMDA Receptor Antagonism are Conserved in Zebrafish Larvae

Dizocilpine maleate (MK-801) is one of several NMDA receptor antagonists that is widely used to pharmacologically model the symptoms of psychosis and schizophrenia in animals. MK-801 elicits behaviors in adult zebrafish (Danio rerio) that are phenotypically consistent with behaviors observed in humans and rodents exposed to tbhe drug. However, the molecular and cellular processes that mediate the psychotomimetic, cognitive and locomotive behaviors of MK-801 are unclear. We exposed zebrafish larvae to MK-801 to assess their merit as a model organism to elucidate the behavioral effects of NMDA receptor blockade. Zebrafish larvae were acutely immersed in MK-801 to assess the effect on spontaneous swimming. MK-801 caused a time- and dose-dependent increase in larval swim speed, and the peak response (a five-fold increase in swim speed) was evoked by a three h exposure to a 20 uM dose. Zebrafish larvae did not exhibit sensitivity to the locomotor effects of MK-801 until 5 dpf, suggesting a critical role for developmental in sensitivity to the drug. Exposure to the low potency NMDA antagonist, memantine, did not alter the swim speed of zebrafish larvae. Co-immersion in D(1) or D(2) dopamine receptor antagonists did not disrupt the time course or magnitude of the increase in swim speed, suggesting dopaminergic signaling is not required for the locomotor actions of MK-801. Our findings of the behavioral actions of MK-801 in zebrafish larvae are consistent with previous observations in mammals and imply that the physiological, cellular and molecular processes disrupted by MK-801 are conserved in zebrafish larvae. These data suggest that the zebrafish larvae is a valid and useful model to elucidate neurobehavioral aspects of NMDA receptor antagonism and may provide insight to the neurobiology of psychosis and schizophrenia.     

Introducing a brief measure of cultural and religious identification in American Jewish identity

The authors conducted 3 studies to develop and investigate the psychometric properties of the American Jewish Identity Scales (AJIS), a brief self-report measure that assesses cultural identification and religious identification. Study 1 assessed the content validity of the item pool using an expert panel. In Study 2, 1,884 Jewish adults completed the initial AJIS and various measures of ethnic identity, collective self-esteem, and religiosity. Using confirmatory factor analyses, the authors selected and cross-validated 33 items that loaded highly and differentially on the 2 theorized latent factors. Study 3 assessed the AJIS's short-term stability and its relation to social desirability. Tests of reliability and construct validity provided initial psychometric support for the measure and confirmed the theorized primary salience of cultural identification. Participants reported significantly more private than public collective self-esteem, and the most Jewish-identified participants reported greater private self-esteem, acculturative stress, and perceived discrimination than did their more assimilated counterparts.