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1.
Article in English | MEDLINE | ID: mdl-37336263

ABSTRACT

BACKGROUND: Previous functional magnetic resonance imaging studies have reported widespread brain functional connectivity alterations in patients with psychosis. These studies have mostly used either resting-state or simple-task paradigms, thereby compromising experimental control or ecological validity, respectively. Additionally, in a conventional functional magnetic resonance imaging intrasubject functional connectivity analysis, it is difficult to identify which connections relate to extrinsic (stimulus-induced) and which connections relate to intrinsic (non-stimulus-related) neural processes. METHODS: To mitigate these limitations, we used intersubject functional connectivity (ISFC) to analyze longitudinal functional magnetic resonance imaging data collected while 36 individuals with first-episode psychosis (FEP) and 29 age- and sex-matched population control participants watched scenes from the fantasy movie Alice in Wonderland at baseline and again at 1-year follow-up. Furthermore, to allow unconfounded comparison and to overcome possible circularity of ISFC, we introduced a novel approach wherein ISFC in both the FEP and population control groups was calculated with respect to an independent group of participants (not included in the analyses). RESULTS: Using this independent-reference ISFC approach, we found an interaction effect wherein the independent-reference ISFC in individuals with FEP, but not in the control group participants, was significantly stronger at baseline than at follow-up in a network centered in the hippocampus and involving thalamic, striatal, and cortical regions, such as the orbitofrontal cortex. Alleviation of positive symptoms, particularly delusions, from baseline to follow-up was correlated with decreased network connectivity in patients with FEP. CONCLUSIONS: These findings link deviation of naturalistic information processing in the hippocampus-centered network to positive symptoms.


Subject(s)
Psychotic Disorders , Humans , Brain , Brain Mapping , Prefrontal Cortex , Hippocampus
2.
Schizophr Res ; 241: 83-91, 2022 03.
Article in English | MEDLINE | ID: mdl-35092893

ABSTRACT

BACKGROUND: Psychotic disorders have been suggested to derive from dysfunctional integration of signaling between brain regions. Earlier studies have found several changes in functional network synchronization as well as altered network topology in patients with psychotic disorders. However, studies have used mainly resting-state that makes it more difficult to link functional alterations to any specific stimulus or experience. We set out to examine functional connectivity as well as graph (topological) measures and their association to symptoms in first-episode psychosis patients during movie viewing. Our goal was to understand whole-brain functional dynamics of complex naturalistic information processing in psychosis and changes in brain functional organization related to symptoms. METHODS: 71 first-episode psychosis patients and 57 control subjects watched scenes from the movie Alice in Wonderland during 3 T fMRI. We compared functional connectivity and graph measures indicating integration, segregation and centrality between groups, and examined the association between topology and symptom scores in the patient group. RESULTS: We identified a subnetwork with predominantly decreased links of functional connectivity in first-episode psychosis patients. The subnetwork was mainly comprised of nodes of and links between the cingulo-opercular, sensorimotor and default-mode networks. In topological measures, we observed between-group differences in properties of centrality. CONCLUSIONS: Functional brain networks are affected during naturalistic information processing already in the early stages of psychosis, concentrated in salience- and cognitive control-related hubs and subnetworks. Understanding these aberrant dynamics could add to better targeted cognitive and behavioral interventions in the early stages of psychotic disorders.


Subject(s)
Psychotic Disorders , Brain/diagnostic imaging , Brain Mapping , Humans , Magnetic Resonance Imaging , Motion Pictures , Nerve Net/diagnostic imaging , Psychotic Disorders/diagnostic imaging
3.
Neuropsychobiology ; 81(1): 39-50, 2022.
Article in English | MEDLINE | ID: mdl-34130283

ABSTRACT

INTRODUCTION: An increase in brain white matter hyperintensities (WMHs) and a decrease in white matter fractional anisotrophy (FA) have been detected in bipolar I (BPI), II (BPII), and major depressive disorder (MDD) patients. Their relationship, and differences in diagnostic groups are obscure. Longitudinal studies are rare. OBJECTIVE: After 5-year follow-up, we evaluated WMHs in BPI, BPII, and MDD patients as compared with controls, and studied the effects of clinical variables. We also explored the associations of clinical variables with cross-sectional whole brain FA. METHODS: Eight BPI, 8 BPII, 6 MDD patients, and 19 controls participated in magnetic resonance imaging at baseline and follow-up. Diffusion weighted imaging was included at follow-up. WMHs were rated by the Coffey scale, and a tract-based spatial statistics method was used for diffusion data. The general linear model, ANOVA, Fisher's exact, Wilcoxon sign, and Kruskal-Wallis tests were used for statistical analyses. RESULTS: Periventricular WMHs were increased in BPI patients (p = 0.047) and associated with the duration of disorder and lifetime occurrence of substance use disorder (p = 0.018). FA decrease was found in the corpus callosum of BPI patients (p < 0.01). MDD patients showed FA decrease in the right cerebellar middle peduncle (RCMP) (p < 0.01). In BPI patients, the duration of disorder associated with FA increase in RCMP (p < 0.05). No FA decrease was detected in patients with WMHs as compared with those without. CONCLUSIONS: Preceding illness burden associated modestly with WMHs, and FA increase in RCMP in BPI patients. MDD patients had FA decrease in RCMP. No association with FA decrease and WMHs was found.


Subject(s)
Bipolar Disorder , Depressive Disorder, Major , White Matter , Bipolar Disorder/diagnostic imaging , Brain/diagnostic imaging , Cross-Sectional Studies , Depressive Disorder, Major/diagnostic imaging , Diffusion Tensor Imaging , Follow-Up Studies , Humans , White Matter/diagnostic imaging
4.
Transl Psychiatry ; 8(1): 283, 2018 12 18.
Article in English | MEDLINE | ID: mdl-30563960

ABSTRACT

Delusion is the most characteristic symptom of psychosis, occurring in almost all first-episode psychosis patients. The motivational salience hypothesis suggests delusion to originate from the experience of abnormal motivational salience. Whether the motivation-related brain circuitries are activated during the actual delusional experience remains, however, unknown. We used a forced-choice answering tree at random intervals during functional magnetic resonance imaging to capture delusional and non-delusional spontaneous experiences in patients with first-episode psychosis (n = 31) or clinical high-risk state (n = 7). The motivation-related brain regions were identified by an automated meta-analysis of 149 studies. Thirteen first-episode patients reported both delusional and non-delusional spontaneous experiences. In these patients, delusional experiences were related to stronger activation of the ventral striatum in both hemispheres. This activation overlapped with the most strongly motivation-related brain regions. These findings provide an empirical link between the actual delusional experience and the motivational salience hypothesis. Further use and development of the present methods in localizing the neurobiological basis of the most characteristic symptoms may be useful in the search for etiopathogenic pathways that result in psychotic disorders.


Subject(s)
Delusions/physiopathology , Motivation/physiology , Psychotic Disorders/physiopathology , Ventral Striatum/physiopathology , Adolescent , Adult , Brain Mapping , Delusions/complications , Female , Humans , Magnetic Resonance Imaging , Male , Psychotic Disorders/complications , Young Adult
5.
Front Psychiatry ; 9: 580, 2018.
Article in English | MEDLINE | ID: mdl-30483163

ABSTRACT

The outcome of first-episode psychosis (FEP) is highly variable, ranging from early sustained recovery to antipsychotic treatment resistance from the onset of illness. For clinicians, a possibility to predict patient outcomes would be highly valuable for the selection of antipsychotic treatment and in tailoring psychosocial treatments and psychoeducation. This selective review summarizes current knowledge of prognostic markers in FEP. We sought potential outcome predictors from clinical and sociodemographic factors, cognition, brain imaging, genetics, and blood-based biomarkers, and we considered different outcomes, like remission, recovery, physical comorbidities, and suicide risk. Based on the review, it is currently possible to predict the future for FEP patients to some extent. Some clinical features-like the longer duration of untreated psychosis (DUP), poor premorbid adjustment, the insidious mode of onset, the greater severity of negative symptoms, comorbid substance use disorders (SUDs), a history of suicide attempts and suicidal ideation and having non-affective psychosis-are associated with a worse outcome. Of the social and demographic factors, male gender, social disadvantage, neighborhood deprivation, dysfunctional family environment, and ethnicity may be relevant. Treatment non-adherence is a substantial risk factor for relapse, but a small minority of patients with acute onset of FEP and early remission may benefit from antipsychotic discontinuation. Cognitive functioning is associated with functional outcomes. Brain imaging currently has limited utility as an outcome predictor, but this may change with methodological advancements. Polygenic risk scores (PRSs) might be useful as one component of a predictive tool, and pharmacogenetic testing is already available and valuable for patients who have problems in treatment response or with side effects. Most blood-based biomarkers need further validation. None of the currently available predictive markers has adequate sensitivity or specificity used alone. However, personalized treatment of FEP will need predictive tools. We discuss some methodologies, such as machine learning (ML), and tools that could lead to the improved prediction and clinical utility of different prognostic markers in FEP. Combination of different markers in ML models with a user friendly interface, or novel findings from e.g., molecular genetics or neuroimaging, may result in computer-assisted clinical applications in the near future.

6.
Psychiatry Res ; 270: 547-553, 2018 12.
Article in English | MEDLINE | ID: mdl-30343240

ABSTRACT

Psychosis is associated with low-grade inflammation as measured by high-sensitivity C-reactive protein (hs-CRP), a risk factor for cardiovascular events and mortality in the general population. We investigated the relationship between hs-CRP and anthropometric and metabolic changes in first-episode psychosis (FEP) during the first treatment year. We recruited 95 FEP patients and 62 controls, and measured longitudinal changes in hs-CRP, weight, waist circumference, insulin resistance, and lipids. We used linear mixed models to analyze the longitudinal relationship between hs-CRP and clinical, anthropometric and metabolic measures. At baseline, patients with FEP had higher levels of insulin resistance, total and low-density lipoprotein cholesterol, apolipoprotein B, and triglycerides. Baseline weight, waist circumference, hs-CRP, fasting glucose, and high-density lipoprotein cholesterol were similar between patients and controls. Marked increases in anthropometric measures and hs-CRP were observed in FEP during the 12-month follow-up. However, glucose and lipid parameters did not change significantly. In the mixed models, waist circumference and female sex were significant predictors of hs-CRP levels in FEP. Prevention of the early development of abdominal obesity in FEP is crucial, as abdominal obesity is accompanied by chronic low-grade inflammation, which increases further the cardiovascular risk in this vulnerable population.


Subject(s)
C-Reactive Protein/analysis , Inflammation/psychology , Psychotic Disorders/blood , Psychotic Disorders/physiopathology , Waist Circumference , Adult , Anthropometry , Cholesterol, HDL/blood , Cholesterol, LDL , Fasting/blood , Female , Humans , Insulin Resistance , Lipids , Male , Middle Aged , Obesity, Abdominal/physiopathology , Obesity, Abdominal/psychology , Sex Factors , Triglycerides/blood
7.
Biol Psychiatry ; 84(9): 655-664, 2018 11 01.
Article in English | MEDLINE | ID: mdl-29885763

ABSTRACT

BACKGROUND: Functional magnetic resonance imaging studies of psychotic disorders have reported both hypoactivity and hyperactivity in numerous brain regions. In line with the dysconnection hypothesis, these regions include cortical integrative hub regions. However, most earlier studies focused on a single cognitive function at a time, assessed by delivering artificial stimuli to patients with chronic psychosis. Thus, it remains unresolved whether these findings are present already in early psychosis and whether they translate to real-life-like conditions that require multisensory processing and integration. METHODS: Scenes from the movie Alice in Wonderland (2010) were shown to 51 patients with first-episode psychosis (16 women) and 32 community-based control subjects (17 women) during 3T functional magnetic resonance imaging. We compared intersubject correlation, a measure of similarity of brain signal time courses in each voxel, between the groups. We also quantified the hubness as the number of connections each region has. RESULTS: Intersubject correlation was significantly lower in patients with first-episode psychosis than in control subjects in the medial and lateral prefrontal, cingulate, precuneal, and parietotemporal regions, including the default mode network. Regional magnitude of between-group difference in intersubject correlation was associated with the hubness. CONCLUSIONS: Our findings provide novel evidence for the dysconnection hypothesis by showing that during complex real-life-like stimulation, the most prominent functional alterations in psychotic disorders relate to integrative brain functions. Presence of such abnormalities in first-episode psychosis rules out long-term effects of illness or medication. These methods can be used in further studies to map widespread hub alterations in a single functional magnetic resonance imaging session and link them to potential downstream and upstream pathways.


Subject(s)
Gyrus Cinguli/physiopathology , Motion Perception/physiology , Parietal Lobe/physiopathology , Prefrontal Cortex/physiopathology , Psychotic Disorders/physiopathology , Adult , Brain Mapping , Case-Control Studies , Female , Gyrus Cinguli/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , Motion Pictures , Neural Pathways/diagnostic imaging , Neural Pathways/physiopathology , Parietal Lobe/diagnostic imaging , Prefrontal Cortex/diagnostic imaging , Psychotic Disorders/diagnostic imaging , Young Adult
8.
Schizophr Res ; 199: 235-242, 2018 09.
Article in English | MEDLINE | ID: mdl-29588124

ABSTRACT

BACKGROUND: Functional connectivity is altered in psychotic disorders. Multiple findings concentrate on the default mode network, anchored on the precuneus-posterior cingulate cortex (PC-PCC). However, the nature of the alterations varies between studies and connectivity alterations have not been studied during an ecologically valid natural stimulus. In the present study, we investigated the functional and structural connectivity of a PC-PCC region, where functioning differentiated first-episode psychosis patients from control subjects during free viewing of a movie in our earlier study. METHODS: 14 first-episode psychosis patients and 12 control subjects were imaged with GE 3T, and 29 patients and 19 control subjects were imaged with a Siemens Skyra 3T scanner while watching scenes from the movie Alice in Wonderland. Group differences in functional connectivity were analysed for both scanners separately and results were compared to identify any overlap. Diffusion tensor measures of 26 patients and 19 control subjects were compared for the related white matter tracts, identified by deterministic tractography. RESULTS: Functional connectivity was increased in patients across scanners between the midline regions of the PC-PCC and the anterior cingulate cortex-medial prefrontal cortex (ACC-mPFC). We found no group differences in any of the diffusion tensor imaging measures. CONCLUSIONS: Already in the early stages of psychosis functional connectivity between the midline structures of the PC-PCC and the ACC-mPFC is consistently increased during naturalistic stimulus.


Subject(s)
Gyrus Cinguli/physiopathology , Motion Perception/physiology , Parietal Lobe/physiopathology , Prefrontal Cortex/physiopathology , Psychotic Disorders/physiopathology , Acute Disease , Adult , Brain Mapping , Female , Gyrus Cinguli/diagnostic imaging , Humans , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Male , Motion Pictures , Neural Pathways/diagnostic imaging , Neural Pathways/physiopathology , Parietal Lobe/diagnostic imaging , Prefrontal Cortex/diagnostic imaging , Psychotic Disorders/diagnostic imaging , White Matter/diagnostic imaging , White Matter/physiopathology
10.
Psychiatry Res ; 258: 374-381, 2017 12.
Article in English | MEDLINE | ID: mdl-28867407

ABSTRACT

In addition to severe traumatic experiences, milder, more common childhood adversities reflecting psychosocial burden may also be common in people with psychotic disorders and have an effect on symptomatology and functioning. We explored eleven negative childhood experiences and their influence on clinical symptoms among young adults with first-episode psychosis (FEP, n = 75) and matched population controls (n = 51). Individuals with FEP reported more adversities than controls. Specifically serious conflicts within the family, bullying at school, maternal mental health problems, and one's own and parents' serious illness during childhood were experienced by the patients more often than by controls. In the FEP group, the severity of adversity was associated with increased anxiety, manic, and obsessive-compulsive symptoms, but not with the severity of positive psychotic symptoms. Adversity produced a more pronounced effect on symptoms in male patients than in female patients. To conclude, in line with earlier studies of more chronic psychosis, a majority of the participants with FEP reported exposure to childhood adversities, with the FEP group reporting more adversities than controls. High levels of mood and anxiety symptoms in patients with FEP may be related to cumulative exposure to childhood adversities. This should be taken into account in the treatment for FEP.


Subject(s)
Anxiety/psychology , Psychotic Disorders/psychology , Stress, Psychological/psychology , Adolescent , Adult , Anxiety/complications , Case-Control Studies , Child , Chronic Disease , Female , Humans , Male , Psychological Trauma/complications , Psychological Trauma/psychology , Psychotic Disorders/complications , Psychotic Disorders/therapy , Stress, Psychological/complications , Young Adult
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