Differing time dependencies of object recognition memory impairments produced by nicotinic and muscarinic cholinergic antagonism in perirhinal cortex

The roles of muscarinic and nicotinic cholinergic receptors in perirhinal cortex in object recognition memory were compared. Rats' discrimination of a novel object preference test (NOP) test was measured after either systemic or local infusion into the perirhinal cortex of the nicotinic receptor antagonist methyllycaconitine (MLA), which targets alpha-7 (α7) amongst other nicotinic receptors or the muscarinic receptor antagonists scopolamine, AFDX-384, and pirenzepine. Methyllycaconitine administered systemically or intraperirhinally before acquisition impaired recognition memory tested after a 24-h, but not a 20-min delay. In contrast, all three muscarinic antagonists produced a similar, unusual pattern of impairment with amnesia after a 20-min delay, but remembrance after a 24-h delay. Thus, the amnesic effects of nicotinic and muscarinic antagonism were doubly dissociated across the 20-min and 24-h delays. The same pattern of shorter-term but not longer-term memory impairment was found for scopolamine whether the object preference test was carried out in a square arena or a Y-maze and whether rats of the Dark Agouti or Lister-hooded strains were used. Coinfusion of MLA and either scopolamine or AFDX-384 produced an impairment profile matching that for MLA. Hence, the antagonists did not act additively when coadministered. These findings establish an important role in recognition memory for both nicotinic and muscarinic cholinergic receptors in perirhinal cortex, and provide a challenge to simple ideas about the role of cholinergic processes in recognition memory: The effects of muscarinic and nicotinic antagonism are neither independent nor additive.     

Prevalence and correlates of suicidal behavior among adult female victims of intimate partner violence

The prevalence and correlates of suicidal threats and attempts among 662 racially and ethnically diverse adult female victims of intimate partner violence (IPV) were studied. One in five women had threatened or attempted suicide during her lifetime. They observed that multiple logistic regression results indicated that women at greater risk of severe or potentially lethal assaults as measured by the Danger Assessment and those who reported having a chronic or disabling illness were more likely to have threatened or attempted suicide. A linear association was found between age and suicide threats/attempts, with younger women having increased odds. Finally, African American IPV victims were less likely to have threatened or attempted suicide as compared to Latina victims. Study implications are discussed.     

Are smokers interested in genetic testing for smoking addiction? A socio-cognitive approach

Genetic advances have made genetically tailored smoking cessation treatments possible. In this study, we examined whether smokers are interested in undergoing a genetic test to identify their genetic susceptibility to nicotine addiction. In addition, we aimed to identify socio-cognitive determinants of smokers' intention to undergo genetic testing. Following the protection motivation theory (PMT), we assessed the following constructs using an online survey among 587 smokers: threat appraisal (i.e. susceptibility and severity), fear, coping appraisal (i.e. response efficacy and self-efficacy), response costs and intention. In addition, knowledge, social norms and information-seeking behaviour were measured. Mean intention rates were 2.57 on a 5-point scale. Intention was significantly associated with threat appraisal and coping appraisal, as predicted by the PMT. Fear of the outcome was negatively associated with the intention to undergo genetic testing, but response costs, knowledge and social influence were not. Intention to undergo genetic testing in turn was positively related to seeking information about genetic testing and genetically tailored smoking cessation treatments. Smokers seem ambivalent or 'on the fence' with regard to undergoing a genetic test for smoking addiction. Socio-cognitive concepts such as susceptibility, severity, response efficacy and self-efficacy may be used to inform or educate smokers about the value of genetically tailored smoking cessation treatments.     

SKOOL versus ZOOL: effects of orthographic and phonological long-term memory on nonword immediate serial recall

In a now-classic study Besner and Davelaar (1982) reported an advantage of pseudohomophone (PSH) over nonword recall in a visual immediate serial recall (ISR) task, which remained under articulatory suppression (AS), and interpreted the findings as indicating PSH items obtain support from stored phonological long-term memory (LTM) representations even when phonological rehearsal is disrupted. However, one key question relating to this PSH effect remains: could the results have been contaminated by a potential confound of orthographic familiarity (i.e., PSH items often look like the word they sound like)? As a result, the present study examined the impact of orthography on PSH ISR. Our findings indicate that PSH accuracy was consistently higher for items that had an orthographic similarity to the parent word, and this effect did not interact with concurrent task. We therefore argue that PSH items in ISR obtain independent support from both orthographic and phonological LTM representations. The present study demonstrates the critical impact of orthographic LTM representations on visual nonword ISR, and we suggest that this may be a fruitful avenue for further research.     

Symbolic magnitude modulates perceptual strength in binocular rivalry

Basic aspects of magnitude (such as luminance contrast) are directly represented by sensory representations in early visual areas. However, it is unclear how symbolic magnitudes (such as Arabic numerals) are represented in the brain. Here we show that symbolic magnitude affects binocular rivalry: perceptual dominance of numbers and objects of known size increases with their magnitude. Importantly, variations in symbolic magnitude acted like variations in luminance contrast: we found that an increase in numerical magnitude of adding one lead to an equivalent increase in perceptual dominance as a contrast increment of 0.32%. Our results support the claim that magnitude is extracted automatically, since the increase in perceptual dominance came about in the absence of a magnitude-related task. Our findings show that symbolic, acculturated knowledge about magnitude interacts with visual perception and affects perception in a manner similar to lower-level aspects of magnitude such as luminance contrast.     

Are children with Specific Language Impairment competent with the pragmatics and logic of quantification?

Specific Language Impairment (SLI) is understood to be a disorder that predominantly affects phonology, morphosyntax and/or lexical semantics. There is little conclusive evidence on whether children with SLI are challenged with regard to Gricean pragmatic maxims and on whether children with SLI are competent with the logical meaning of quantifying expressions. We use the comprehension of statements quantified with ‘all’, ‘none’, ‘some’, ‘some…not’, ‘most’ and ‘not all’ as a paradigm to study whether Spanish-speaking children with SLI are competent with the pragmatic maxim of informativeness, as well as with the logical meaning of these expressions.Children with SLI performed more poorly than a group of age-matched typically-developing peers, and both groups performed more poorly with pragmatics than with logical meaning. Moreover, children with SLI were disproportionately challenged by pragmatic meaning compared to their age-matched peers. However, the performance of children with SLI was comparable to that of a group of younger language-matched typically-developing children. The findings document that children with SLI do face difficulties with employing the maxim of informativeness, as well as with understanding the logical meaning of quantifiers, but also that these difficulties are in keeping with their overall language difficulties rather than exceeding them. The implications of these findings for SLI, linguistic theory, and clinical practice are discussed.     

Relations among language exposure, phonological memory, and language development in Spanish-English bilingually developing 2-year-olds

The relation of phonological memory to language experience and development was investigated in 41 Spanish-English bilingual first language learners. The children’s relative exposure to English and Spanish and their phonological memory for English- and Spanish-like nonwords were assessed at 22 months of age, and their productive vocabulary and grammar in both languages were assessed at 25 months of age. Phonological memory for English-like nonwords was highly correlated with that for Spanish-like nonwords, and each was related to vocabulary and grammar in both languages, suggesting a language-general component to phonological memory skill. In addition, there was evidence of language-specific benefits of language exposure to phonological memory skill and of language-specific benefits of phonological memory skill to language development.     

Does money really matter? Estimating impacts of family income on young children's achievement with data from random-assignment experiments

Social scientists do not agree on the size and nature of the causal impacts of parental income on children's achievement. We revisit this issue using a set of welfare and antipoverty experiments conducted in the 1990s. We utilize an instrumental variables strategy to leverage the variation in income and achievement that arises from random assignment to the treatment group to estimate the causal effect of income on child achievement. Our estimates suggest that a $1,000 increase in annual income increases young children's achievement by 5%-6% of a standard deviation. As such, our results suggest that family income has a policy-relevant, positive impact on the eventual school achievement of preschool children.     

Emotional state affects the initiation of forward gait

The aim of the current study was to determine the extent to which pleasant and unpleasant emotional states impact the initiation of forward gait. Participants initiated gait and walked for several steps following the presentation of low arousing pleasant, high arousing pleasant, low arousing unpleasant, high arousing unpleasant, and neutral pictures. Reaction time, displacement, and velocity of the center of pressure (COP) trajectory, and length and velocity of the first and second steps were calculated. Exposure to the highly arousing unpleasant pictures reduced reaction times compared to all other affective conditions. Compared to the low arousing unpleasant pictures, exposure to the high and low arousing pleasant pictures increased the displacement of the COP movement during the anticipatory postural adjustment phase of gait initiation. Additionally, exposure to the low arousing pleasant pictures increased the velocity of the COP movement during the anticipatory postural adjustment phase, compared to the high and low arousing unpleasant pictures. Exposure to the high and low arousing pleasant pictures increased the velocity of the first step relative to the low arousing unpleasant pictures. These findings demonstrate that highly arousing unpleasant emotional states accelerate the initial motor response, but pleasant emotional states generally facilitate the initiation of forward gait due to the approach-oriented directional salience of the movement. These findings extend the scope of the motivational direction hypothesis by demonstrating the effects of emotional reactivity on the initiation of gait.