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Individuals with schizophrenia exhibit deficits in facial emotion processing, which have been associated with abnormalities in visual gaze behavior and functional brain activation. However, the relationship between gaze behavior and brain activation in schizophrenia remains unexamined. Studies in healthy individuals and other clinical samples indicate a relationship between gaze behavior and functional activation in brain regions implicated in facial emotion processing deficits in schizophrenia (e.g., fusiform gyrus), prompting the question of whether a similar relationship exists in schizophrenia. This study examined whether manipulating visual scanpaths during facial emotion perception would modulate functional brain activation in a sample of 23 schizophrenia patients and 26 community controls. Participants underwent functional magnetic resonance imaging (MRI) while viewing pictures of emotional faces. During the typical viewing condition, a fixation cue directed participants' gaze primarily to the eyes and mouth, whereas during the atypical viewing condition gaze was directed to peripheral features. Both viewing conditions elicited a robust response throughout face-processing regions. Typical viewing led to greater activation in visual association cortex including the right inferior occipital gyrus/occipital face area, whereas atypical viewing elicited greater activation in primary visual cortex and regions involved in attentional control. There were no between-groups activation differences in response to faces or interaction between group and gaze manipulation. The results indicate that gaze behavior modulates functional activation in early face-processing regions in individuals with and without schizophrenia, suggesting that abnormal gaze behavior in schizophrenia may contribute to activation abnormalities during facial emotion perception. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Attempts to determine the cognitive benefits of adaptive working memory training in healthy adults has resulted in a polarized and stagnating field. Heterogeneous approaches and problematic methodological choices have contributed to the controversy. Structural neuroimaging has the potential to identify biological changes present after working memory training, which could go undetected by cognitive outcome tasks. In this study, 24 healthy community dwelling adults aged 18 - 40 years underwent structural magnetic resonance neuroimaging (MRI) before and after completing a 6-week n-back working memory training program. An active control group (n = 24) completed 6-weeks of processing speed training using the same computerized platform and neuroimaging protocol. Cortical surface area, thickness, and volume measurements were collected in a-priori regions of interest in the frontal and parietal lobes. Subcortical and total gray matter volumes were also measured. Group by time repeated measures Analyses of Variance (RM-ANOVAs) were conducted to identify changes in surface area, thickness, or volume measurements associated with training type over time. Null results were present across all neuroanatomical metrics after correction for multiple comparisons. Findings of this study, in concert with recently published investigations, support the idea that adaptive n-back working memory training is not an effective method for inducing neuroanatomical change. Further investigation into other forms of training may help advance the field., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: People with schizophrenia may demonstrate cortical abnormalities, with gyri and sulci potentially being differentially affected., Aims: To measure frontal and temporal sulcal cortical thickness, surface area and volume in the non-psychotic relatives of patients with schizophrenia as a potential vulnerability indicator for the disorder., Method: An automated parcellation method was used to measure the superior frontal, inferior frontal, cingulate, superior temporal and inferior temporal sulci in the relatives of patients (n=19) and controls (n=22)., Results: Compared with controls, relatives had reversed hemispheric asymmetry in their cingulate sulcal thickness and a bilateral reduction in their superior temporal sulcal thickness., Conclusions: Cingulate and superior temporal sulcal thickness abnormalities may reflect neural abnormalities associated with the genetic liability to schizophrenia. Cortical thinning in these regions suggests that liability genes affect the dendrites, synapses or myelination process during the neurodevelopment of the cortical mantle.

First-degree relatives of patients diagnosed with schizophrenia (SZ-FDRs) show similar patterns of brain abnormalities and cognitive alterations to patients, albeit with smaller effect sizes. First-degree relatives of patients diagnosed with bipolar disorder (BD-FDRs) show divergent patterns; on average, intracranial volume is larger compared to controls, and findings on cognitive alterations in BD-FDRs are inconsistent. Here, we performed a meta-analysis of global and regional brain measures (cortical and subcortical), current IQ, and educational attainment in 5,795 individuals (1,103 SZ-FDRs, 867 BD-FDRs, 2,190 controls, 942 schizophrenia patients, 693 bipolar patients) from 36 schizophrenia and/or bipolar disorder family cohorts, with standardized methods. Compared to controls, SZ-FDRs showed a pattern of widespread thinner cortex, while BD-FDRs had widespread larger cortical surface area. IQ was lower in SZ-FDRs (d = -0.42, p = 3 × 10-5 ), with weak evidence of IQ reductions among BD-FDRs (d = -0.23, p = .045). Both relative groups had similar educational attainment compared to controls. When adjusting for IQ or educational attainment, the group-effects on brain measures changed, albeit modestly. Changes were in the expected direction, with less pronounced brain abnormalities in SZ-FDRs and more pronounced effects in BD-FDRs. To conclude, SZ-FDRs and BD-FDRs show a differential pattern of structural brain abnormalities. In contrast, both had lower IQ scores and similar school achievements compared to controls. Given that brain differences between SZ-FDRs and BD-FDRs remain after adjusting for IQ or educational attainment, we suggest that differential brain developmental processes underlying predisposition for schizophrenia or bipolar disorder are likely independent of general cognitive impairment.

Poor emotion recognition is a core deficit in schizophrenia and is associated with poor functional outcome. Functional magnetic resonance imaging (fMRI) multivariate analysis methods were used to elucidate the neural underpinnings of face and emotion processing associated with both genetic liability and disease-specific effects. Schizophrenia patients, relatives, and controls completed a task that included 4 facial emotion discrimination conditions and an age discrimination condition during fMRI. Three functional networks were derived from the data: the first involved in visual attention and response generation, the second a default mode network (DMN), and a third involved in face and emotion processing. No differences in activation were found between groups for the visual attention and response generation network, suggesting that basic processes were intact. Both schizophrenia patients and relatives showed evidence for hyperdeactivation in the DMN compared to controls, with relatives being intermediate, suggesting a genetic liability effect. Both diseasespecific and genetic liability effects were found for the face processing network, which included the amygdala. Patients exhibited lower coordinated network activity compared to controls and relatives across all facial discrimination conditions. Additionally, in relation to the other emotion discrimination conditions, a heightened coordinated response during fear and anger discrimination was observed in schizophrenia compared to other conditions, whereas relatives demonstrated heightened coordinated activity for anger discrimination only relative to other emotion conditions. With regards to brain functioning, this study found that schizophrenia is associated with abnormal processing of threat-related information, and that in part may be associated with the genetic risk for the disorder, suggesting that the facial and emotion processing network could be targeted for intervention. [ABSTRACT FROM AUTHOR]

Training of working memory as a method of increasing working memory capacity and fluid intelligence has received much attention in recent years. This burgeoning field remains highly controversial with empirically-backed disagreements at all levels of evidence, including individual studies, systematic reviews, and even meta-analyses. The current study investigated the effect of a randomized six week online working memory intervention on untrained cognitive abilities in a community-recruited sample of healthy young adults, in relation to both a processing speed training active control condition, as well as a no-contact control condition. Results of traditional null hypothesis significance testing, as well as Bayesian factor analyses, revealed support for the null hypothesis across all cognitive tests administered before and after training. Importantly, all three groups were similar at pre-training for a variety of individual variables purported to moderate transfer of training to fluid intelligence, including personality traits, motivation to train, and expectations of cognitive improvement from training. Because these results are consistent with experimental trials of equal or greater methodological rigor, we suggest that future research re-focus on: 1) other promising interventions known to increase memory performance in healthy young adults, and; 2) examining sub-populations or alternative populations in which working memory training may be efficacious. [ABSTRACT FROM AUTHOR]

Temporal lobe abnormalities and emotion recognition deficits are prominent features of schizophrenia and appear related to the diathesis of the disorder. This study investigated whether temporal lobe structural abnormalities were associated with facial emotion recognition deficits in schizophrenia and related to genetic liability for the disorder. Twenty-seven schizophrenia patients, 23 biological family members, and 36 controls participated. Several temporal lobe regions (fusiform, superior temporal, middle temporal, amygdala, and hippocampus) previously associated with face recognition in normative samples and found to be abnormal in schizophrenia were evaluated using volumetric analyses. Participants completed a facial emotion recognition task and an age recognition control task under time-limited and self-paced conditions. Temporal lobe volumes were tested for associations with task performance. Group status explained 23% of the variance in temporal lobe volume. Left fusiform gray matter volume was decreased by 11% in patients and 7% in relatives compared with controls. Schizophrenia patients additionally exhibited smaller hippocampal and middle temporal volumes. Patients were unable to improve facial emotion recognition performance with unlimited time to make a judgment but were able to improve age recognition performance. Patients additionally showed a relationship between reduced temporal lobe gray matter and poor facial emotion recognition. For the middle temporal lobe region, the relationship between greater volume and better task performance was specific to facial emotion recognition and not age recognition. Because schizophrenia patients exhibited a specific deficit in emotion recognition not attributable to a generalized impairment in face perception, impaired emotion recognition may serve as a target for interventions. [ABSTRACT FROM PUBLISHER]

Abstract: One of the fundamental goals in understanding schizophrenia is linking the observable symptoms to the underlying unobservable pathophysiology. Given recent advances in medical imaging, researchers are increasingly investigating brain-behavior relationships to better understand the neural substrates of negative, positive, and disorganization symptoms in schizophrenia. This review focused on 25 task-related functional magnetic resonance imaging studies and found meaningful small to moderate associations between specific symptom dimensions and regional brain activity. Negative symptoms were related to the functioning of the ventrolateral prefrontal cortex and ventral striatum. Positive symptoms, particularly persecutory ideation, were related to functioning of the medial prefrontal cortex, amygdala, and hippocampus/parahippocampal region. Disorganization symptoms, although less frequently evaluated, were related to functioning of the dorsolateral prefrontal cortex. Surprisingly, no symptom domain had a consistent relationship with the middle or superior temporal regions. While a number of adaptations in experimental design and reporting standards can facilitate this work, current neuroimaging approaches appear to provide a number of consistent links between the manifest symptoms of schizophrenia and brain dysfunction. [Copyright &y& Elsevier]

• VBA showed lower MK in corona radiata and posterior association fibers in BD. • Lower MK and KA found in connections traversing temporal and occipital lobes in BD. • Lower mean AK in right cerebellar, thalamo-subcortical pathways in BD. • Significant differences were not seen in DTI metrics following FDR-correction. White matter pathology likely contributes to the pathogenesis of bipolar disorder (BD). Most studies of white matter in BD have used diffusion tensor imaging (DTI), but the advent of more advanced multi-shell diffusion MRI imaging offers the possibility to investigate other aspects of white matter microstructure. Diffusion kurtosis imaging (DKI) extends the DTI model and provides additional measures related to diffusion restriction. Here, we investigated white matter in BD by applying whole-brain voxel-based analysis (VBA) and a network-based connectivity approach using constrained spherical deconvolution tractography to assess differences in DKI and DTI metrics between BD (n = 25) and controls (n = 24). The VBA showed lower mean kurtosis in the corona radiata and posterior association fibers in BD. Regional differences in connectivity were indicated by lower mean kurtosis and kurtosis anisotropy in streamlines traversing the temporal and occipital lobes, and lower mean axial kurtosis in the right cerebellar, thalamo-subcortical pathways in BD. Significant differences were not seen in DTI metrics following FDR-correction. The DKI findings indicate altered connectivity across cortical, subcortical and cerebellar areas in BD. DKI is sensitive to different microstructural properties and is a useful complementary technique to DTI to more fully investigate white matter in BD. [ABSTRACT FROM AUTHOR]

Abstract: Neuropsychological and neurophysiological studies provide evidence for abnormal interhemispheric communication in schizophrenia. These abnormalities may have a substrate in structural irregularities of the corpus callosum. This study investigated schizophrenia patients (n=27) and healthy comparison subjects (n=31). Global and regional measurements of the corpus callosum were acquired from one midsagittal SPGR slice. Eight subregions were approximately matched to fiber pathways from cortical regions. Overall effects of diagnosis [Wilks'' Lambda F(8,46)=2.45, p=0.03] and diagnosis by age interaction [Wilks'' Lambda F(8,46)=2.58, p=0.02] were found in a MANCOVA of the eight functionally specific subregions. Specifically, chronic schizophrenia was associated with a smaller rostral body [lower by 6.9%, F(1,53)=9.70, p=0.003] and anterior midbody [lower by 9.7%, F(1,53)=4.89, p=0.03] subregions. The rostral body and anterior midbody subregions of the corpus callosum primarily have premotor, supplementary motor, and motor cortical fibers transversing through them. Functional abnormalities of the associated cortical regions are reported in schizophrenia. These novel findings suggest that structural abnormalities of the corpus callosum exist in schizophrenia, with perhaps the motor-specific subregions affected more than others. Structural differences in the corpus callosum may be a substrate for interhemispheric functional dysconnectivity in schizophrenia. [Copyright &y& Elsevier]

Stress has a detrimental impact on memory, the hippocampus, and psychological health. Psychopathology research on stress has centered mainly on psychiatric diagnoses rather than symptom dimensions, and less attention has been given to the neurobiological factors through which stress might be translated into psychopathology. The present work investigates the transdiagnostic relationship of cumulative stress with episodic memory and the hippocampus (both structure and function) and explores the extent to which stress mediates the relationship between personality psychopathology and hippocampal size and activation. Cumulative lifetime stress was assessed in a sample of females recruited to vary in stress exposure and severity of personality psychopathology. Fifty-six participants completed subjective and objective tests of episodic memory, a T2-weighted high-resolution magnetic resonance imaging (MRI) scan of the medial-temporal lobe, and functional MRI (fMRI) scanning during a learning and recognition memory task. Higher cumulative stress was significantly related to memory complaints (but not episodic memory performance), lower bilateral hippocampal volume, and greater encoding-related hippocampal activation during the presentation of novel stimuli. Furthermore, cumulative stress significantly mediated the relationship between personality psychopathology and both hippocampal volume and activation, whereas alternative mediation models were not supported. The findings suggest that structural and functional activation differences in the hippocampus observed in case-control studies of psychiatric diagnoses may share cumulative stress as a common factor, which may mediate broadly reported relationships between psychopathology and hippocampal structure and function. [ABSTRACT FROM AUTHOR]

Objective: The authors performed a longitudinal study of the effects on thalamic volume of switching from typical to atypical antipsychotic medications. Method: Magnetic resonance imaging scans were acquired from 10 subjects with chronic schizophrenia taking typical antipsychotics and 20 healthy volunteers. Subjects with schizophrenia were switched to olanzapine; both groups were rescanned. Results: At baseline, thalamic volumes in subjects with chronic schizophrenia were 5.8% greater than those of healthy volunteers. At follow-up, there was no significant difference between groups. Additional analysis revealed a significant positive correlation between baseline thalamic volume and dosage of typical antipsychotic medication. Higher dosages at baseline were correlated with larger reductions in volume after the switch to olanzapine. Conclusions: Antipsychotic medication effects may be a factor in the wide range of thalamic volume differences reported between subjects with schizophrenia and healthy volunteers. [ABSTRACT FROM AUTHOR]

Background: Brain networks involved in language, attentional and response processes are detectable by fMRI during lexical decision (LD). Here, we investigated possible abnormalities in the functional networks involved in LD in patients with bipolar disorder (BD).Methods: fMRI and behavioural data were compared between BD (n = 25) and control (n = 21), with groups matched for age and sex. The functional brain networks involved in LD were extracted by manipulating the "word-likeness" of LD stimuli and using a multidimensional analysis method.Results: Attentional, response and language processes were captured in separate function-specific brain networks (default mode network, response network, linguistic processing network, respectively) in the BD and control groups, replicating the results of our previous study in an independent group of healthy adults. Behaviourally, the BD group showed higher performance than the control group in the LD task. Activity in the default mode network (DMN) and the linguistic processing network (LPN) did not differ between the groups, but the BD group had higher activation than the control group in the response network (RESP).Limitations: Due to the small sample, the study is underpowered, capable of only detecting large effects.Conclusions: The results suggest that BD may be associated with sustained activity in the RESP network, which might contribute to psychomotor dysfunction in BD. Future studies should investigate the possible link between altered RESP activation and psychomotor disturbances in BD, as well as the basis for altered RESP activity in BD. [ABSTRACT FROM AUTHOR]

Background: Deficits in facial emotion perception in schizophrenia may be a marker of disorder liability. Previous functional magnetic resonance imaging (fMRI) studies investigating these deficits have been limited by task demands that may recruit other impaired cognitive processes in schizophrenia.Methods: We used a family study design along with a passive viewing task during fMRI to investigate brain activation abnormalities underlying facial emotion perception in schizophrenia and examine whether such abnormalities are associated with the genetic liability to the disorder. Twenty-eight schizophrenia patients, 27 nonpsychotic relatives, and 27 community controls passively viewed images of facial emotions during an fMRI scan.Results: Analyses revealed hypoactivation in face processing areas for both patients and relatives compared to controls, and hyperactivation in relatives compared to both patients and controls for frontal regions implicated in emotion processing.Conclusions: Results suggest that activation abnormalities during facial emotion perception are manifestations of the genetic liability to schizophrenia, and may be accompanied by compensatory mechanisms in relatives. Studying mechanisms in nonpsychotic relatives is a valuable way to examine effects of the unexpressed genetic liability to schizophrenia on the brain and behaviour. [ABSTRACT FROM AUTHOR]