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Urbanization is a trend lasting for more than one century worldwide. Four hundred ninety male and female adult Chinese Han participants with different urban and rural childhoods were included in this study. Early-life urban environment was found benefit for total grey matter volume (GMV), dorsolateral prefrontal cortex (DLPFC) GMV, temporal pole (TP) GMV and cognition function, and negatively correlated with medial prefrontal cortex (MPFC) GMV. Regression analysis showed that maternal education was a protective factor for total and DLPFC GMVs, while having siblings was better for MPFC GMV. Total, DLPFC and TP GMVs acts mediation effects between childhood urbanicity and different cognitive domains. These findings may suggest some pros and cons on brain structure associated with childhood urbanicity and related environmental factors., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Working memory is a limited capacity system that integrates and manipulates information across brief periods of time, engaging a network of prefrontal, parietal and subcortical brain regions. Genetic control of these heritable brain processes have been suggested by functional genetic variations influencing dopamine signalling, which affect prefrontal activity during complex working memory tasks. However, less is known about genetic control over component working memory cortical–subcortical networks in humans, and the pharmacogenetic implications of dopamine-related genes on cognition in patients receiving anti-dopaminergic drugs. Here, we examined predictions from basic models of dopaminergic signalling in cortical and cortical–subcortical circuitries implicated in dissociable working memory maintenance and manipulation processes. We also examined pharmacogenetic effects on cognition in the context of anti-dopaminergic drug therapy. Using dynamic causal models of functional magnetic resonance imaging in normal subjects (n = 46), we identified differentiated effects of functional polymorphisms in COMT, DRD2 and AKT1 genes on prefrontal–parietal and prefrontal–striatal circuits engaged during maintenance and manipulation, respectively. Cortical synaptic dopamine monitored by the COMT Val158Met polymorphism influenced prefrontal control of both parietal processing in working memory maintenance and striatal processing in working memory manipulation. DRD2 and AKT1 polymorphisms implicated in DRD2 signalling influenced only the prefrontal–striatal network associated with manipulation. In the context of anti-psychotic drugs, the DRD2 and AKT1 polymorphisms altered dose-response effects of anti-psychotic drugs on cognition in schizophrenia (n = 111). Thus, we suggest that genetic modulation of DRD2–AKT1-related prefrontal–subcortical circuits could at least in part influence cognitive dysfunction in psychosis and its treatment. [ABSTRACT FROM PUBLISHER]

There has been relatively little study of the longitudinal course of cognitive functioning before the onset of schizophrenia. We report scores from standardized academic examinations at ages 12 and 16 years of 30 male patients with a first episode of schizophrenia (FES) and a normal control group balanced for gender, age, parental socio–economic class and academic scores at age 12. The FES group had greater deterioration in mathematics scores and poorer educational outcome, possibly reflecting neurocognitive changes that preceded the onset of schizophrenia. [Copyright &y& Elsevier]

Objective: The objective of this study is to provide a retrospective description of prodromal symptoms of young military servicemen with first-episode psychosis, and a comparison with first-episode non-psychotic disorders. Method: Thirty consecutive servicemen presenting with first-episode psychosis were studied. Thirty-four randomly selected servicemen from 123 with non-psychotic disorders served as comparison. A combination of unstructured and semistructured interviews with the patient and other informants was used to describe the prodromal symptoms. Results: The most common prodromal psychotic symptoms were social withdrawal (83%); anxiety (77%); sleep disturbance (77%); disturbance in attention, concentration or memory (73%); deterioration in studies in school (70%); depressed mood (63%); odd behaviour (53%); and anger or irritability (53%). Common symptoms found in first-episode psychosis and non-psychotic patients included sleep disturbance, anxiety, depressed mood and anger or irritability. Common symptoms that were associated with the psychotic prodrome were social withdrawal (p < 0.001), deterioration in school results (p < 0.001) and disturbance in attention, concentration or memory (p < 0.001). The psychotic prodrome was also associated with apathy (p < 0.001), odd behaviour (p < 0.001), doing nothing (p = 0.004) and thought blocking (p = 0.04). Conclusion: Cognitive disturbances and attenuated negative symptoms appear to be more specific to the psychotic prodrome in young patients with first-episode psychosis. [ABSTRACT FROM AUTHOR]

Background: Episodic memory (EM) declines with age and the rate of decline is variable across individuals. A single nucleotide polymorphism (rs17070145) in the WWC1 gene that encodes the KIBRA protein critical for long-term potentiation and memory consolidation has previously been associated with EM performance, as well as differences in hippocampal engagement during EM tasks using functional magnetic resonance imaging (fMRI). In the current study, we explore the effect of this polymorphism on EM-related activity and cognitive performance across the adult life span using fMRI. Methods: Two hundred thirty-two healthy, Caucasian subjects (18–89 years) completed a battery of cognitive tests, as well as an EM task during an fMRI scan. Results: WWC1 T carriers had significantly better delayed recall performance than CC individuals (p = .006). The relationship between increasing age and recall scores (immediate and delayed) was also significantly different between WWC1 genotype groups (p = .01). In addition to the age-related decline in hippocampal formation (HF) activation (p < .05; false discovery ratesmall volume correction -HF-region of interest), we observed an age by WWC1 genotype interaction on HF activation during encoding and retrieval. The CC group showed a significant negative association between HF activity and increasing age, while no such association was observed in the T carrier group (left HF p = .04; r-z correlation difference during encoding and retrieval; right HF p = .0008; r-z correlation difference during retrieval). Conclusions: Our results show a dynamic relationship between rs17070145 polymorphism and increasing age on neuronal activity in the hippocampal region. [Copyright &y& Elsevier]

Abstract: The default mode network (DMN) is a set of functionally connected brain regions which shows deactivation (task-induced deactivation, TID) during a cognitive task. Evidence shows an age-related decline in task-load-related modulation of the activity within the DMN during cognitive tasks. However, the effect of age on the functional coupling within the DMN and their relation to cognitive performance has hitherto been unexplored. Using functional magnetic resonance imaging, we investigated functional connectivity within the DMN in older and younger subjects during a working memory task with increasing task load. Older adults showed decreased connectivity and ability to suppress low frequency oscillations of the DMN. Additionally, the strength of the functional coupling of posterior cingulate (pCC) with medial prefrontal cortex (PFC) correlated positively with performance and was lower in older adults. pCC was also negatively coupled with task-related regions, namely the dorsolateral PFC and cingulate regions. Our results show that in addition to changes in canonical task-related brain regions, normal aging is also associated with alterations in the activity and connectivity of brain regions within the DMN. These changes may be a reflection of a deficit in cognitive control associated with advancing age that results in deficient resource allocation to the task at hand. [Copyright &y& Elsevier]