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1.
Article En | MEDLINE | ID: mdl-38110742

Motivation in general, and social motivation in particular are important for interpersonal functioning in individuals with schizophrenia. Still, their roles after accounting for social cognition, are not well understood. The sample consisted of 147 patients with schizophrenia. General motivation was measured using the Behavioral inhibition/activation scale (BIS/BAS). Social motivation was measured by Passive social withdrawal and Active social avoidance items from PANSS. Interpersonal functioning was evaluated with Birchwood's Social Functioning Scale (SFS). We used Exploratory Graph Analysis for network estimation and community detection. Active social avoidance, passive social withdrawal, and social withdrawal/engagement (from SFS) were the most important nodes. In addition, three distinct communities were identified: Social cognition, Social motivation, and Interpersonal functioning. Notably, the BIS and BAS measures of general motivation were not part of any community. BAS showed stronger links to functioning than BIS. Passive social withdrawal was more strongly linked to interpersonal functioning than social cognitive abilities. Results suggest that social motivation, especially social approach, is more closely related to interpersonal functioning in schizophrenia than general motivation. In contrast, we found that general motivation was largely unrelated to social motivation. This pattern highlights the importance of type of motivation for understanding variability in interpersonal difficulties in schizophrenia.

2.
Schizophr Bull ; 49(6): 1422-1424, 2023 11 29.
Article En | MEDLINE | ID: mdl-37672342

There is mounting evidence that the social determinants of psychosis operate via a long and circuitous route. Here, we comment on the striking findings from a recent study by Ku et al., that area-level social environmental factors yield social disability and increased risk for schizophrenia through intervening variables and over a long time course. We discuss the relevance of animal models of social isolation to understand how environmental factors interrelate with individual-level mechanisms. We also discuss treatment implications, including the search for novel psychopharmacological treatments for reduced social motivation, and the need for a comprehensive prediction and prevention model.


Psychotic Disorders , Schizophrenia , Animals , Social Interaction , Social Determinants of Health , Psychotic Disorders/etiology , Psychotic Disorders/therapy , Schizophrenia/etiology , Schizophrenia/therapy , Models, Animal
3.
Neuropsychologia ; 188: 108621, 2023 09 09.
Article En | MEDLINE | ID: mdl-37321406

BACKGROUND: Individuals with psychosis spectrum disorders (PSD) have difficulty developing social relationships. This difficulty may reflect reduced response to social feedback involving functional alterations in brain regions that support the social motivation system: ventral striatum, orbital frontal cortex, insula, dorsal anterior cingulate cortex, and amygdala. Whether these alterations span PSD is unknown. METHODS: 71 individuals with PSD, 27 unaffected siblings, and 37 control participants completed a team-based fMRI task. After each trial, participants received performance feedback paired with the expressive face of a teammate or opponent. A 2 × 2 (win versus loss outcome x teammate versus opponent) repeated measures ANOVA by group was performed on activation in the five key regions of interest during receipt of feedback. RESULTS: Across groups, three social motivation regions, ventral striatum, orbital frontal cortex, and amygdala, showed sensitivity to feedback (significant main effect of outcome), with greater activation during win versus loss trials, regardless of whether the feedback was from a teammate or opponent. In PSD, ventral striatum and orbital frontal cortex activation to win feedback was negatively correlated with social anhedonia scores. CONCLUSIONS: Patterns of neural activation during social feedback were similar in PSD, their unaffected siblings, and healthy controls. Across the psychosis spectrum, activity in key social motivation regions during social feedback was associated with individual differences in social anhedonia.


Anhedonia , Psychotic Disorders , Humans , Anhedonia/physiology , Motivation , Brain Mapping , Psychotic Disorders/diagnostic imaging , Neuroimaging , Magnetic Resonance Imaging , Reward
4.
Psychiatry Res Neuroimaging ; 327: 111556, 2022 12.
Article En | MEDLINE | ID: mdl-36327867

Functional connectome organization is altered in schizophrenia (SZ) and bipolar disorder (BD). However, it remains unclear whether network reorganization during a task relative to rest is also altered in these disorders. This study examined connectome organization in patients with SZ (N = 43) and BD (N = 42) versus healthy controls (HC; N = 39) using fMRI data during a visual object-perception task and at rest. Graph analyses were conducted for the whole-brain network using indices selected a priori: three reflecting network segregation (clustering coefficient, local efficiency, modularity), two reflecting integration (characteristic path length, global efficiency). Group differences were limited to network segregation and were more evident in SZ (clustering coefficient, modularity) than in BD (clustering coefficient) compared to HC. State differences were found across groups for segregation (local efficiency) and integration (characteristic path length). There was no group-by-state interaction for any graph index. In summary, aberrant network organization compared to HC was confirmed, and was more evident in SZ than in BD. Yet, reorganization was largely intact in both disorders. These findings help to constrain models of dysconnection in SZ and BD, suggesting that the extent of functional dysconnectivity in these disorders tends to persist across changes in mental state.


Bipolar Disorder , Connectome , Schizophrenia , Humans , Bipolar Disorder/diagnostic imaging , Schizophrenia/diagnostic imaging , Brain/diagnostic imaging , Visual Perception
5.
J Psychiatr Res ; 156: 1-7, 2022 12.
Article En | MEDLINE | ID: mdl-36201975

Several studies of reward processing in schizophrenia have shown reduced sensitivity to positive, but not negative, outcomes although inconsistencies have been reported. In addition, few studies have investigated whether patients show a relative deficit to social versus nonsocial rewards, whether deficits occur across the spectrum of psychosis, or whether deficits relate to negative symptoms and functioning. This study examined probabilistic implicit learning via two visually distinctive slot machines for social and nonsocial rewards in 101 outpatients with diverse psychotic disorders and 48 community controls. The task consisted of two trial types: positive (optimal to choose a positive vs. neutral machine) and negative (optimal to choose a neutral vs. negative machine), with two reward conditions: social (faces) and nonsocial (money) reward conditions. A significant group X trial type interaction indicated that controls performed better on positive than negative trials, whereas patients showed the opposite pattern of better performance on negative than positive trials. In addition, both groups performed better for social than nonsocial stimuli, despite lower overall task performance in patients. Within patients, worse performance on negative trials showed significant, small-to-moderate correlations with motivation and pleasure-related negative symptoms and social functioning. The current findings suggest reward processing disturbances, particularly decreased sensitivity to positive outcomes, extend beyond schizophrenia to a broader spectrum of psychotic disorders and relate to important clinical outcomes.


Psychotic Disorders , Humans
6.
Schizophr Res ; 246: 250-257, 2022 08.
Article En | MEDLINE | ID: mdl-35843157

Event-related potential (ERP) studies of motivated attention in schizophrenia typically show intact sensitivity to affective vs. non-affective images depicting diverse types of content. However, it is not known whether this ERP pattern: 1) extends to images that solely depict social content, (2) applies across a broad sample with diverse psychotic disorders, and (3) relates to self-reported trait social anhedonia. We examined late positive potential (LPP) amplitudes to images involving people that were normatively pleasant (affiliative), unpleasant (threatening), or neutral in 97 stable outpatients with various psychotic disorders and 38 healthy controls. Both groups showed enhanced LPP to pleasant and unpleasant vs. neutral images to a similar degree, despite lower overall LPP in patients. Within the patients, there were no significant LPP differences among subgroups (schizophrenia vs. other psychotic disorders; affective vs. non-affective psychosis) for the valence effect (pleasant/unpleasant vs. neutral). Higher social anhedonia showed a small, significant relation to lower LPP to pleasant images across all groups. These findings suggest intact motivated attention to social images extends across psychotic disorder subgroups. Dimensional transdiagnostic analyses revealed a modest association between self-reported trait social anhedonia and an LPP index of neural sensitivity to pleasant affiliative images.


Anhedonia , Psychotic Disorders , Brain/physiology , Electroencephalography/methods , Emotions/physiology , Evoked Potentials/physiology , Humans
7.
Neurosci Biobehav Rev ; 135: 104558, 2022 04.
Article En | MEDLINE | ID: mdl-35122780

Chronic pain remains one of the most persistent healthcare challenges in the world. To advance pain treatment, experts have recently introduced research-driven subtypes of chronic pain based on proposed underlying mechanisms. Nociplastic pain (e.g., nonspecific chronic low back or fibromyalgia) is one such subtype which may involve a greater etiologic role for brain plasticity, painful emotions induced by life stress and trauma, and unhealthy emotion regulation. In particular, correlational and behavioral data link anger and the ways anger is regulated with the presence and severity of nociplastic pain. Functional neuroimaging studies also suggest nociplastic pain and healthy anger regulation demonstrate inverse patterns of activity in the medial prefrontal cortex and amygdala; thus, improving anger regulation could normalize activity in these regions. In this Mini-Review, we summarize these findings and propose a unified, biobehavioral model called the Anger, Brain, and Nociplastic Pain (AB-NP) Model, which can be tested in future research and may advance pain care by informing new treatments that address anger, anger regulation, and brain plasticity for nociplastic pain.


Chronic Pain , Amygdala/physiology , Anger/physiology , Brain , Emotions/physiology , Humans
9.
Schizophr Bull Open ; 1(1): sgaa056, 2020 Jan.
Article En | MEDLINE | ID: mdl-33313506

Visual processing abnormalities in schizophrenia (SZ) are poorly understood, yet predict functional outcomes in the disorder. Bipolar disorder (BD) may involve similar visual processing deficits. Converging evidence suggests that visual processing may be relatively normal at early stages of visual processing such as early visual cortex (EVC), but that processing abnormalities may become more pronounced by mid-level visual areas such as lateral occipital cortex (LO). However, little is known about the connectivity of the visual system in SZ and BD. If the flow of information to, from, or within the visual system is disrupted by reduced connectivity, this could help to explain perceptual deficits. In the present study, we performed a targeted analysis of the structural and functional connectivity of the visual system using graph-theoretic metrics in a sample of 48 SZ, 46 BD, and 47 control participants. Specifically, we calculated parallel measures of local efficiency for EVC and LO from both diffusion weighted imaging data (structural) and resting-state (functional) imaging data. We found no structural connectivity differences between the groups. However, there was a significant group difference in functional connectivity and a significant group-by-region interaction driven by reduced LO connectivity in SZ relative to HC, whereas BD was approximately intermediate to the other 2 groups. We replicated this pattern of results using a different brain atlas. These findings support and extend theoretical models of perceptual dysfunction in SZ, providing a framework for further investigation of visual deficits linked to functional outcomes in SZ and related disorders.

10.
Behav Brain Res ; 379: 112307, 2020 02 03.
Article En | MEDLINE | ID: mdl-31678217

Working memory (WM) and long term memory (LTM) are different neuropsychological processes, although distinction between these domains is an area of debate. LTM is thought to rely on hippocampal circuitry. Cognitive neuroscience models imply that WM processing may at least partially support LTM within regions of the prefrontal cortex (PFC). We sought to determine the association between PFC based WM processing and LTM in the visuospatial domain. In contrast to prior work, we aimed to query if WM was involved in learning and free recall trials as measured by standard neuropsychological tests of LTM. Forty-three older adults (24 with a diagnosis of amnestic Mild Cognitive Impairment and 19 elderly controls) were included in the analysis. Patients completed a fMRI task of visuospatial maintenance WM in which they were required to match a previously studied complex shape with one of two probes. Extent of activity in the right PFC during the WM task was tabulated for each patient. Hippocampal volume was quantified from T1 scans. On a separate day patients completed neuropsychological testing, including the Brief Visuospatial Memory Test- Revised (BVMT-R), which includes learning trials (total recall), delayed free recall, and recognition. Right PFC activity was associated with performance on BVMT-R total recall and delayed recall. Results from multiple regression showed that PFC activity explained an additional 9 % of the variance in memory performance above right hippocampal volume. These findings suggest that PFC processing that supports WM (including stimuli maintenance, retrieval, and selection) are also involved in LTM learning and recall.


Cognitive Dysfunction/physiopathology , Hippocampus/pathology , Memory, Episodic , Memory, Long-Term/physiology , Memory, Short-Term/physiology , Mental Recall/physiology , Prefrontal Cortex/physiology , Aged , Aged, 80 and over , Cognitive Dysfunction/diagnostic imaging , Female , Hippocampus/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , Neuroimaging , Prefrontal Cortex/diagnostic imaging , Space Perception/physiology , Visual Perception/physiology
11.
Hum Brain Mapp ; 40(16): 4703-4715, 2019 11 01.
Article En | MEDLINE | ID: mdl-31322784

Individuals with schizophrenia and bipolar disorder show alterations in functional neural connectivity during rest. However, resting-state network (RSN) disruptions have not been systematically compared between the two disorders. Further, the impact of RSN disruptions on social cognition, a key determinant of functional outcome, has not been studied. Forty-eight individuals with schizophrenia, 46 with bipolar disorder, and 48 healthy controls completed resting-state functional magnetic resonance imaging. An atlas-based approach was used to examine functional connectivity within nine RSNs across the cortex. RSN connectivity was assessed via nonparametric permutation testing, and associations with performance on emotion perception, mentalizing, and emotion management tasks were examined. Group differences were observed in the medial and lateral visual networks and the sensorimotor network. Individuals with schizophrenia demonstrated reduced connectivity relative to healthy controls in all three networks. Individuals with bipolar disorder demonstrated reduced connectivity relative to controls in the medial visual network and connectivity within this network was significantly positively correlated with emotion management. In healthy controls, connectivity within the medial and lateral visual networks positively correlated with mentalizing. No significant correlations were found for either visual network in schizophrenia. Results highlight the role of altered early visual processing in social cognitive deficits in both schizophrenia and bipolar disorder. However, individuals with bipolar disorder appear to compensate for disrupted visual network connectivity on social cognitive tasks, whereas those with schizophrenia do not. The current study adds clarity on the neurophysiology underlying social cognitive deficits that result in impaired functioning in serious mental illness.


Bipolar Disorder/diagnostic imaging , Bipolar Disorder/psychology , Cognition , Nerve Net/diagnostic imaging , Schizophrenia/diagnostic imaging , Schizophrenic Psychology , Social Behavior , Adolescent , Adult , Aged , Brain Mapping , Cognition Disorders/diagnostic imaging , Cognition Disorders/psychology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Rest , Young Adult
12.
PLoS One ; 14(5): e0214303, 2019.
Article En | MEDLINE | ID: mdl-31100068

Social cognitive skills training interventions for psychotic disorders have shown improvement in social cognitive performance tasks, but little was known about brain-based biomarkers linked to treatment effects. In this pilot study, we examined whether social cognitive skills training could modulate extrinsic and intrinsic functional connectivity in psychosis using functional magnetic resonance imaging (fMRI). Twenty-six chronic outpatients with psychotic disorders were recruited from either a Social Cognitive Skills Training (SCST) or an activity- and time-matched control intervention. At baseline and the end of intervention (12 weeks), participants completed two social cognitive tasks: a Facial Affect Matching task and a Mental State Attribution Task, as well as resting-state fMRI (rs-fMRI). Extrinsic functional connectivity was assessed using psychophysiological interaction (PPI) with amygdala and temporo-parietal junction as a seed region for the Facial Affect Matching Task and the Mental State Attribution task, respectively. Intrinsic functional connectivity was assessed with independent component analysis on rs-fMRI, with a focus on the default mode network (DMN). During the Facial Affect Matching task, we observed stronger PPI connectivity in the SCST group after intervention (compared to baseline), but no treatment-related change in the Control group. Neither group showed treatment-related changes in PPI connectivity during the Mental State Attribution task. During rs-fMRI, we found treatment-related changes in the DMN in the SCST group, but not in Control group. This study found that social cognitive skills training modulated both extrinsic and intrinsic functional connectivity in individuals with psychotic disorders after a 12-week intervention. These findings suggest treatment-related changes in functional connectivity as a potential brain-based biomarker of social cognitive skills training.


Cognition , Magnetic Resonance Imaging , Psychotic Disorders/diagnosis , Psychotic Disorders/psychology , Social Skills , Adult , Biomarkers , Brain Mapping/methods , Computational Biology/methods , Connectome , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging/methods , Male , Middle Aged , Protein Interaction Mapping , Psychotic Disorders/therapy , Treatment Outcome
13.
Schizophr Bull ; 45(3): 620-628, 2019 04 25.
Article En | MEDLINE | ID: mdl-30189096

BACKGROUND: Human beings find social stimuli rewarding, which is thought to facilitate efficient social functioning. Although reward processing has been extensively studied in schizophrenia, a few studies have examined neural processes specifically involved in social reward processing. This study examined neural sensitivity to social and nonsocial rewards in schizophrenia. METHODS: Twenty-seven patients with schizophrenia and 25 community controls completed a One-Armed Bandit Task, an implicit reinforcement learning task, in the scanner. There were 2 conditions with an identical trial structure, one with social rewards and the other with nonsocial rewards. The data were analyzed using a region of interest (ROI) approach, focusing on the ventral striatum, ventromedial prefrontal cortex, and anterior cingulate cortex. RESULTS: Across all 3 ROIs, patients showed reduced activation for social rewards compared to controls. However, the 2 groups showed comparable levels of activation for nonsocial rewards. Within the patient group, levels of neural activation in these ROIs during the social reward condition were associated with better performance. CONCLUSIONS: This study found reduced neural sensitivity in patients with schizophrenia in key reward-processing regions for social but not for nonsocial rewards. These findings suggest a relatively specific social reward-processing deficit in schizophrenia during an implicit reinforcement learning task.


Brain Mapping , Gyrus Cinguli/physiopathology , Motivation/physiology , Prefrontal Cortex/physiopathology , Reward , Schizophrenia/physiopathology , Social Perception , Ventral Striatum/physiopathology , Adult , Female , Gyrus Cinguli/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Prefrontal Cortex/diagnostic imaging , Schizophrenia/diagnostic imaging , Ventral Striatum/diagnostic imaging
14.
Neuroimage Clin ; 20: 380-387, 2018.
Article En | MEDLINE | ID: mdl-30128276

Social perceptual deficits in schizophrenia are well established. Recent work suggests that the ability to extract social information from bodily cues is reduced in patients. However, little is known about the neurobiological mechanisms underlying this deficit. In the current study, 20 schizophrenia patients and 16 controls completed two tasks using point-light animations during fMRI: a basic biological motion task and an emotion in biological motion task. The basic biological motion task was used to localize activity in posterior superior temporal sulcus (pSTS), a critical region for biological motion perception. During the emotion in biological motion task, participants viewed brief videos depicting happiness, fear, anger, or neutral emotions and were asked to decide which emotion was portrayed. Activity in pSTS and amygdala was interrogated during this task. Results indicated that patients showed overall reduced activation compared to controls in pSTS and at a trend level in amygdala across emotions, despite similar task performance. Further, a functional connectivity analysis revealed that controls, but not patients, showed significant positive connectivity between pSTS and left frontal regions as well as bilateral angular gyrus during the emotion in biological motion task. These findings indicate that schizophrenia patients show aberrant neural activity and functional connectivity when extracting complex social information from simple motion stimuli, which may contribute to social perception deficits in this disorder.


Brain/diagnostic imaging , Emotions , Motion Perception/physiology , Schizophrenia/diagnostic imaging , Schizophrenic Psychology , Social Perception , Adult , Amygdala/diagnostic imaging , Amygdala/physiology , Brain/physiology , Brain Mapping/methods , Brief Psychiatric Rating Scale , Emotions/physiology , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Photic Stimulation/methods , Temporal Lobe/diagnostic imaging , Temporal Lobe/physiology
15.
Neuroimage Clin ; 19: 970-981, 2018.
Article En | MEDLINE | ID: mdl-30003034

Poor executive functioning increases risk of decline in Mild Cognitive Impairment (MCI). Executive functioning can be conceptualized within the framework of working memory. While some components are responsible for maintaining representations in working memory, the central executive is involved in the manipulation of information and creation of new representations. We aimed to examine the neural correlates of these components of working memory using a maintenance working memory and visuospatial reasoning task. Twenty-five patients with amnestic MCI and 19 elderly controls (EC) completed functional MRI during reasoning and maintenance working memory tasks. In MCI, maintenance working memory was associated with hypoactivation of right frontoparietal regions and hyperactivation of left prefrontal cortex, coupled with attenuation of default mode network (DMN) relative to EC. During reasoning, MCI showed hypoactivation of parietal regions, coupled with attenuation of anterior DMN and increased deactivation of posterior DMN relative to EC. Comparing the reasoning task to the maintenance working memory task yields the central executive. In MCI, the central executive showed hypoactivation of right parietal lobe and increased deactivation of posterior DMN compared to EC. Consistent with prior work on executive functioning, MCI show different neural circuitry during visuospatial reasoning, including changes to both task positive frontoparietal regions, as well as to deactivation patterns within the DMN. Both hyperactivation of task positive networks and increased deactivation of DMN may be compensatory.


Brain/diagnostic imaging , Cognitive Dysfunction/diagnostic imaging , Executive Function/physiology , Memory, Short-Term/physiology , Nerve Net/diagnostic imaging , Aged , Aged, 80 and over , Brain Mapping , Cognitive Dysfunction/psychology , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neuropsychological Tests
16.
Neuropsychologia ; 109: 19-27, 2018 01 31.
Article En | MEDLINE | ID: mdl-29217224

BACKGROUND: Enhanced memory for self-oriented information is known as the self-referential memory (SRM) effect. fMRI studies of the SRM effect have focused almost exclusively on encoding, revealing selective engagement of the medial prefrontal cortex (mPFC) during "self" relative to other processing conditions. Other critical areas for self-processing include ventrolateral prefrontal cortex (vlPFC), temporo-parietal junction (TPJ) and posterior cingulate/precuneus (PCC/PC). Previous behavioral studies show that individuals with schizophrenia fail to benefit from this memory boost. However, the neural correlates of this deficit, at either encoding or retrieval, are unknown. METHODS: Twenty individuals with schizophrenia and 16 healthy controls completed an event-related fMRI SRM paradigm. During encoding, trait adjectives were judged in terms of structural features ("case" condition), social desirability ("other" condition), or as self-referential ("self" condition). Participants then completed an unexpected recognition test (retrieval phase). We examined BOLD activation during both encoding and retrieval within mPFC, vlPFC, TPJ, and PCC/PC regions-of-interest (ROIs). RESULTS: During encoding, fMRI data indicated both groups had greater activation during the "self" relative to the "other" condition across ROIs. Controls showed this primarily in mPFC whereas patients showed this in PCC/PC. During retrieval, fMRI data indicated controls showed differentiation across ROIs between "self" and "other" conditions, but patients did not. CONCLUSIONS: Results suggest regional differences in the neural processing of self-referential information in individuals with schizophrenia, perhaps because representation of the self is not as well established in patients relative to controls. The current study presents novel findings that add to the literature implicating impaired self-oriented processing in schizophrenia.


Brain/physiopathology , Memory/physiology , Schizophrenia/physiopathology , Schizophrenic Psychology , Self Concept , Adult , Brain/diagnostic imaging , Brain Mapping , Cerebrovascular Circulation , Female , Humans , Judgment/physiology , Magnetic Resonance Imaging , Male , Middle Aged , Oxygen/blood , Schizophrenia/diagnostic imaging , Schizophrenia/drug therapy
17.
Psychiatry Res Neuroimaging ; 261: 35-43, 2017 Mar 30.
Article En | MEDLINE | ID: mdl-28126618

Individuals with schizophrenia demonstrate difficulties in attending to important stimuli (e.g., targets) and ignoring distractors (e.g., non-targets). We used a visual oddball task during fMRI to examine functional connectivity within and between the ventral and dorsal attention networks to determine the relative contribution of each network to detection of rare visual targets in schizophrenia. The sample comprised 25 schizophrenia patients and 27 healthy controls. Psychophysiological interaction analysis was used to examine whole-brain functional connectivity in response to targets. We used the right temporo parietal junction (TPJ) as the seed region for the ventral network and the right medial intraparietal sulcus (IPS) as the seed region for the dorsal network. We found that connectivity between right IPS and right anterior insula (AI; a component of the ventral network) was significantly greater in controls than patients. Expected patterns of within- and between-network connectivity for right TPJ were observed in controls, and not significantly different in patients. These findings indicate functional connectivity deficits between the dorsal and ventral attention networks in schizophrenia that may create problems in processing relevant versus irrelevant stimuli. Understanding the nature of network disruptions underlying cognitive deficits of schizophrenia may help shed light on the pathophysiology of this disorder.


Attention/physiology , Brain/physiopathology , Nerve Net/physiopathology , Schizophrenia/physiopathology , Visual Perception/physiology , Adult , Brain/diagnostic imaging , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Nerve Net/diagnostic imaging , Schizophrenia/diagnostic imaging
18.
Cereb Cortex ; 27(5): 2984-2993, 2017 05 01.
Article En | MEDLINE | ID: mdl-27226446

Patients with schizophrenia show specific abnormalities in visual perception, and patients with bipolar disorder may have related perceptual deficits. During tasks that highlight perceptual dysfunction, patients with schizophrenia show abnormal activity in visual brain areas, including the lateral occipital complex (LOC) and early retinotopic cortex. It is unclear whether the anatomical structure of those visual areas is atypical in schizophrenia and bipolar disorder. In members of those two patient groups and healthy controls, we localized LOC and early retinotopic cortex individually for each participant using functional magnetic resonance imaging (MRI), then measured the thickness of those regions of interest using structural MRI scans. In both regions, patients with schizophrenia had the thinnest cortex, controls had the thickest cortex, and bipolar patients had intermediate cortical thickness. A control region, motor cortex, did not show this pattern of group differences. The thickness of each visual region of interest was significantly correlated with performance on a visual object masking task, but only in schizophrenia patients. These findings suggest an anatomical substrate for visual processing abnormalities that have been found with both neural and behavioral measures in schizophrenia and other severe mental illnesses.


Bipolar Disorder/complications , Schizophrenia/complications , Sensation Disorders/etiology , Sensation Disorders/pathology , Visual Cortex/pathology , Visual Perception/physiology , Adolescent , Adult , Aged , Bipolar Disorder/diagnostic imaging , Female , Follow-Up Studies , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Neuropsychological Tests , Oxygen/blood , Perceptual Masking , Photic Stimulation , Schizophrenia/diagnostic imaging , Sensation Disorders/diagnostic imaging , Visual Cortex/diagnostic imaging , Young Adult
19.
Front Psychol ; 7: 323, 2016.
Article En | MEDLINE | ID: mdl-27014135

Early visual perception and attention are impaired in schizophrenia, and these deficits can be observed on target detection tasks. These tasks activate distinct ventral and dorsal brain networks which support stimulus-driven and goal-directed attention, respectively. We used single and dual target rapid serial visual presentation (RSVP) tasks during fMRI with an ROI approach to examine regions within these networks associated with target detection and the attentional blink (AB) in 21 schizophrenia outpatients and 25 healthy controls. In both tasks, letters were targets and numbers were distractors. For the dual target task, the second target (T2) was presented at three different lags after the first target (T1) (lag1 = 100 ms, lag3 = 300 ms, lag7 = 700ms). For both single and dual target tasks, patients identified fewer targets than controls. For the dual target task, both groups showed the expected AB effect with poorer performance at lag 3 than at lags 1 or 7, and there was no group by lag interaction. During the single target task, patients showed abnormally increased deactivation of the temporo-parietal junction (TPJ), a key region of the ventral network. When attention demands were increased during the dual target task, patients showed overactivation of the posterior intraparietal cortex, a key dorsal network region, along with failure to deactivate TPJ. Results suggest inefficient and faulty suppression of salience-oriented processing regions, resulting in increased sensitivity to stimuli in general, and difficulty distinguishing targets from non-targets.

20.
Soc Cogn Affect Neurosci ; 11(5): 783-92, 2016 05.
Article En | MEDLINE | ID: mdl-26746181

Although it has been proposed that schizophrenia is characterized by impaired empathy, several recent studies found intact neural responses on tasks measuring the affective subdomain of empathy. This study further examined affective empathy in 21 schizophrenia outpatients and 21 healthy controls using a validated pain empathy paradigm with two components: (i) observing videos of people described as medical patients who were receiving a painful sound stimulation treatment; (ii) listening to the painful sounds (to create regions of interest). The observing videos component incorporated experimental manipulations of perspective taking (instructions to imagine 'Self' vs 'Other' experiencing pain) and cognitive appraisal (information about whether treatment was 'Effective' vs 'Not Effective'). When considering activation across experimental conditions, both groups showed similar dorsal anterior cingulate cortex (dACC) and anterior insula (AI) activation while merely observing others in pain. However, there were group differences associated with perspective taking: controls showed relatively greater dACC and AI activation for the Self vs Other contrast whereas patients showed relatively greater activation in these and additional regions for the Other vs Self contrast. Although patients demonstrated grossly intact neural activity while observing others in pain, they showed more subtle abnormalities when required to toggle between imagining themselves vs others experiencing pain.


Cerebral Cortex/physiology , Empathy/physiology , Magnetic Resonance Imaging/methods , Pain Perception/physiology , Schizophrenia/physiopathology , Social Perception , Adult , Cerebral Cortex/physiopathology , Female , Gyrus Cinguli/physiology , Gyrus Cinguli/physiopathology , Humans , Male , Middle Aged
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