Spatial learning in rats is impaired by microinfusions of protein kinase C-gamma antisense oligodeoxynucleotide within the nucleus accumbens

The nucleus accumbens (NAcc) has been shown to play a role in motor and spatial learning. Protein kinase C (PKC) has been implicated in the mechanisms of initiation and maintenance of long-term potentiation that is thought to be involved in the storage of long-term memory. In the present study, the importance of de novo synthesis of PKC-gamma within the NAcc in the acquisition and retention of spatial discrimination learning was assessed using an antisense knockdown approach. Separate groups of Long-Evans rats were exposed to acute microinfusions (6microg/microl) of PKC-gamma antisense oligodeoxynucleotide (AS-ODN), control oligodeoxynucleotide (C-ODN) or vehicle into the NAcc at 24 and 3h before each training session. Behavioral findings showed that the blockade of NAcc-PKC-gamma translation caused impairments in the early phase of learning and retention of spatial information. Biochemical experiments showed that PKC-gamma expression was reduced and Ca(2+)/phospholipid-dependent protein kinase C (PKC) activity was blocked significantly in the AS-ODN-treated rats in comparison with control rats. The present findings suggest that NAcc-PKC-gamma plays a role during the early acquisition of spatial learning. Also, retention test results suggest that NAcc-PKC-gamma may be working as an intermediate factor involved in the onset of molecular mechanisms necessary for spatial memory consolidation within the NAcc.     

Allophonic mode of speech perception in dyslexia

Perceptual discrimination between speech sounds belonging to different phoneme categories is better than that between sounds falling within the same category. This property, known as "categorical perception," is weaker in children affected by dyslexia. Categorical perception develops from the predispositions of newborns for discriminating all potential phoneme categories in the world's languages. Predispositions that are not relevant for phoneme perception in the ambient language are usually deactivated during early childhood. However, the current study shows that dyslexic children maintain a higher sensitivity to phonemic distinctions irrelevant in their linguistic environment. This suggests that dyslexic children use an allophonic mode of speech perception that, although without straightforward consequences for oral communication, has obvious implications for the acquisition of alphabetic writing. Allophonic perception specifically affects the mapping between graphemes and phonemes, contrary to other manifestations of dyslexia, and may be a core deficit.     

Beyond the individual: the impact of ethnic context and classroom behavioral norms on victims' adjustment

With a sample of 1,630 sixth-grade students from 77 classrooms, the authors used hierarchical linear modeling to examine how ethnicity within context and classroom social disorder influenced the association between peer victimization and social-psychological adjustment (loneliness and social anxiety). Victimized students in classrooms where many classmates shared their ethnicity reported feeling the most loneliness and social anxiety. Additionally, classroom-level social disorder served as a moderator such that the association between victimization and anxiety was stronger in classrooms with low social disorder. Both findings were interpreted as evidence that problem behavior deviating from what is perceived as normative in a particular context heightens maladjustment. The authors discuss implications for studying ethnicity and classroom behavioral norms as context variables in peer relations.     

Contour grouping inside and outside of facial contexts

We examine how contours group in isolation compared with when they are embedded in face-like contexts. As previously shown, contours that seem to group by phenomenological observation also show powerful effects on task performance: with contours that group, selective attention to one while ignoring another is poor (as indexed by Garner Interference (GI), but not Stroop Interference), whereas divided attention across contours is good. With contours that do not group, however, the reverse happens. Here we test pairs of curved lines (parentheses) displayed either in isolation or within contexts including cartoon faces, where these curves may serve as mouths or eyebrows. The results with isolated contours replicate previous findings of poor selective attention, but within face-like contexts the same contours showed nearly perfect selective attention (i.e., zero GI). Thus, contour grouping was weaker inside than outside of faces, a finding that contrasts with the widely-held belief that faces are processed configurally, not by local features.     

Once hurt,twice hurtful: how perceived regard regulates daily marital interactions

A daily diary study examined how chronic perceptions of a partner's regard affect how intimates interpret and respond to daily relationship stresses. Spouses each completed a diary for 21 days. Multilevel analyses revealed that people who felt less positively regarded read more into stressful events than did people who felt highly regarded, feeling more hurt on days after acute threats, such as those posed by a moody or ill-behaved partner. Intimates who felt less valued responded to feeling hurt by behaving badly toward their partner on subsequent days. In contrast, intimates who felt more valued responded to feeling hurt by drawing closer to their partner. Ironically, chronically activated needs for belongingness might lead people who are trying to find acceptance to undermine their marriage.     

Comprehension of indirect requests by persons with fluent aphasia

This study examined the judgments and response latencies of 10 participants with aphasia and 10 participants without aphasia for responses to indirect requests. Modals such as can and should were drawn from 5 indirect request categories. There was a significant difference in judgment errors and response latency between participants with and without aphasia. There were no significant differences between aphasic participants' judgments for literal versus nonliteral contrasts. There was a significant effect among the modals and among the categories of indirect requests. Response latency reflected aphasic participants' understanding of these indirect requests.     

Affective, behavioral, and cognitive functioning in adolescents with multiple suicide attempts

The purpose of this study was to examine affective, behavioral, and cognitive functioning in adolescents with multiple suicide attempts. Forty-seven adolescents with a history of multiple suicide attempts (MA) were compared to 74 single suicide attempters (SA) on psychiatric diagnosis, depressive symptoms, affect regulation, self-mutilation, alcohol use, and hopelessness. Results revealed that the MA group was more likely to be diagnosed with a mood disorder, and reported more severe depressive symptoms and anger, in comparison to the SA group. Behaviorally, the MA group had higher rates of disruptive behavior disorders and higher levels of affect dysregulation and serious self-mutilation than the SA group. Further, greater levels of hopelessness were reported by the MA than the SA group. After controlling for a mood disorder diagnosis, only differences in anger, affect dysregulation, and serious self-mutilation remained significant. Overall, results suggest that treatment with adolescent suicide attempters might specifically target anger and affect dysregulation to reduce risk for future suicidal behavior.     

Developments in long-term explicit memory late in the first year of life: behavioral and electrophysiological indices

Coincident with developments in the temporal-cortical explicit memory network, long-term recall abilities are newly emergent late in the first year of human life. We recorded event-related potentials (ERPs) in 9-month-olds as an index of the integrity of the neural substrate underlying a task thought to reflect explicit memory, namely, deferred imitation. ERP measures of recognition memory 1 week after unique laboratory experiences predicted whether and how much infants recalled of the experiences 1 month later. The findings further imply that memory storage and consolidation processes are a major source of variability in long-term recall memory late in the first year of life.     

Constructing a short form of the Smoking Consequences Questionnaire with adolescents and young adults

The goal of the present studies was to construct and validate a short form of the 50-item Smoking Consequences Questionnaire (SCQ; T.H. Brandon & T. B. Baker, 1991), a measure of smoking outcome expectancies. In Study 1, a 21-item short form (S-SCQ) was derived from a sample of 107 young adults previously treated for substance abuse. In Study 2, the measure was cross-validated on 125 adolescents in treatment for substance abuse. Confirmatory factor analyses revealed good model fit and factorial invariance for the 4 S-SCQ subscales across both samples. Validation analyses on each sample found that subscale scores generally correlated significantly with smoking-related variables. The present studies provide initial evidence for the utility of the S-SCQ when used with young adults and adolescents.