Beyond heritability: neurotransmitter genes differentially modulate visuospatial attention and working memory

A cued, visuospatial attention task and a working memory task were administered to 89 healthy adults genotyped for a T-to-C polymorphism in CHRNA4, a nicotinic receptor subunit gene. Increasing gene dose of the C allele of the CHRNA4 gene (i.e., no C alleles, one C allele, two C alleles) was associated with increased reaction time (RT) benefits of valid attentional cuing and reduced RT costs of invalid cues, but was not associated with working memory performance. In a second experiment, 103 healthy persons were genotyped for a G-to-A polymorphism of the dopamine beta-hydroxylase (DBH) gene. Increasing gene dose of the G allele of the DBH gene was associated with increased working memory accuracy at a high memory load. However, there was no consistent association between the DBH gene and visuospatial attention. Thus, a double dissociation was observed, with visuospatial attention associated with CHRNA4 but not the DBH gene and, conversely, working memory associated with the DBH gene but not CHRNA4. The results show that normal allelic variations in single neurotransmitter genes modulate individual differences in processing components of cognitive functions in healthy individuals.     

Dimensionality of the Beck Youth Inventories With Child Psychiatric Outpatients

The Anxiety, Depression, Anger, Disruptive Behavior, and Self-Concept Inventories of the Beck Youth Inventories of Emotional and Social Impairment (J. S. Beck, A. S. Beck, & J. Jolly, 2001) were administered to 150 female and 150 male outpatients who were 7–12 years old and matched by sex as to whether they were diagnosed with anxiety, mood, adjustment, or attention-deficit and disruptive behavior disorders to determine whether each inventory represented distinct symptom dimensions. Horns parallel analyses (J. L. Horn, 1965) found that the Anxiety, Depression, and Disruptive Behavior Inventories were unidimensional, but that the Anger and Self-Concept Inventories were each composed of two underlying dimensions. Iterated principal-factor analyses indicated that the Anger Inventory represented Affective and Cognitive dimensions, whereas the Self-concept Inventory reflected Self-Esteem and Competency dimensions. However, the overall pattern of results was discussed as supporting the current practice of scoring each inventory as a summative scale for clinical assessment purposes.     

Factorial validity of the Conners' Parent Rating Scale-revised: short form with psychiatric outpatients

To assess the factorial validity of the 27-item Conners' Parent Rating Scale-Revised: Short Form (CPRS-R:S; Conners, 1997), 100 (50%) male and 100 (50%) female psychiatric outpatients between 5 and 16 years old were rated by a parent. A confirmatory factor analysis of the 18 item ratings from the CPRS-R:S Oppositional, Cognitive Problems, and Hyperactivity scales provided only tentative support for scoring these scales as Conners (1997) recommended. However, an exploratory principal-axis factor analysis with all 27 item ratings found 2 dimensions: 1 dimension was composed of the 6 items in the Oppositional scale, and other dimension contained the remaining 21 items. An attention deficit hyperactivity disorder (ADHD) Total Symptoms scale was constructed by summing the ratings for these 21 symptom ratings, and this scale was found to be as effective as the Hyperactivity scale was in discriminating between youth who were and were not eventually diagnosed with an ADHD. We discuss the results as providing an alternate way of scoring the CPRS-R:S to screen for an ADHD in child and adolescent psychiatric outpatients.     

In support of anti-intellectualism

Intellectualist theories attempt to assimilate know how to propositional knowledge and, in so doing, fail to properly explain the close relation know how bears to action. I develop here an anti-intellectualist theory that is warranted, I argue, because it best accounts for the difference between know how and mere “armchair knowledge.” Know how is a mental state characterized by a certain world-to-mind direction of fit (though it is non-motivational) and attendant functional role. It is essential of know how, but not propositional knowledge, that it makes possible performance errors and has the functional role of guiding action. The theory is attractive, in part, because it allows for propositional, non-propositional and perhaps even non-representational varieties of know how.     

Does Gratitude Promote Resilience During a Pandemic? An Examination of Mental Health and Positivity at the Onset of COVID-19

Journal of Happiness Studies - Researchers have emphasized the detrimental effects of COVID-19 on mental health, but less attention has been given to personal strengths promoting resilience during...     

‘Knowledge’ as a natural kind term

Naturalists who conceive of knowledge as a natural kind are led to treat ‘knowledge’ as a natural kind term. ‘Knowledge,’ then, must behave semantically in the ways that seem to support a direct reference theory for other natural kind terms. A direct reference theory for ‘knowledge,’ however, appears to leave open too many possibilities about the identity of knowledge. Intuitively, states of belief count as knowledge only if they meet epistemic criteria, not merely if they bear a causal/historical relation to the term. I will develop this objection and show that it is grounded in modal considerations central to Kripke’s work on reference. I will also argue that a more plausible externalist semantics for natural kind terms disarms the objection.     

Activation of shape and semantic information during ambiguous homophone processing: eye tracking evidence from Hindi

In two visual world eye tracking studies, we examined the activation of subordinate meanings of ambiguous homophones in Hindi and particularly when the sentence context is biased towards the dominant meaning. Participants listened to sentences that were either neutral or biased towards the dominant meaning of the homophone and saw a display containing four pictures. In experiment 1, the display had a shape competitor of the subordinate meaning of the homophone in both neutral and biased conditions along with three unrelated distractors. Experiment 2 had semantic competitors of the subordinate meaning of the homophones along with three distractors. Proportion of fixations to different objects overtime suggested that participants activated the subordinate meanings and oriented their attention to the shape and semantic competitors even when the prior context was biased towards the dominant meaning. Overall, these data from Hindi provide further support to those models of lexical access that assume exhaustive access of both the meanings of an ambiguous homophone. These data suggest even a dominant bias does not eliminate the activation of perceptual and conceptual features of the subordinate meaning.     

‘Age-hardened alloy’ based on bulk polycrystalline oxide ceramic

We report here for the first time the development of ‘age-hardened/toughened’ ceramic alloy based on MgO in the bulk polycrystalline form. This route allows for the facile development of a ‘near-ideal’ microstructure characterized by the presence of nanosized and uniformly dispersed second-phase particles (MgFe₂O₄) within the matrix grains, as well as along the matrix grain boundaries, in a controlled manner. Furthermore, the intragranular second-phase particles are rendered coherent with the matrix (MgO). Development of such microstructural features for two-phase bulk polycrystalline ceramics is extremely challenging following the powder metallurgical route usually adopted for the development of bulk ceramic nanocomposites. Furthermore, unlike for the case of ceramic nanocomposites, the route adopted here does not necessitate the usage of nano-powder, pressure/electric field-assisted sintering techniques and inert/reducing atmosphere. The as-developed bulk polycrystalline MgO–MgFe₂O₄ alloys possess considerably improved hardness (by ~52%) and indentation toughness (by ~35%), as compared to phase pure MgO.