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Research paper thumbnail of Schizotypy and personality profiles of Cluster A in a group of schizophrenic patients and their siblings

BMC Psychiatry, 2013

Background: Schizotypy, or the set of personality traits related to schizophrenia, is considered ... more Background: Schizotypy, or the set of personality traits related to schizophrenia, is considered an endophenotypic manifestation that is more represented in first-degree relatives of patients with schizophrenia than in the general population. The assessment of schizotypy is primarily based on self-reports, and for this reason it presents several limitations. In order to assess schizotypy, this study proposes a diagnostic instrument based on clinical reports.

Research paper thumbnail of Poster #S53 MEDIAL FRONTAL GYRUS ALTERATIONS IN SCHIZOPHRENIA: RELATIONSHIP WITH DURATION OF ILLNESS AND EXECUTIVE DYSFUNCTION

Research paper thumbnail of Schizotypy and personality profiles of Cluster A in a group of schizophrenic patients and their siblings

BMC Psychiatry, 2013

Background: Schizotypy, or the set of personality traits related to schizophrenia, is considered ... more Background: Schizotypy, or the set of personality traits related to schizophrenia, is considered an endophenotypic manifestation that is more represented in first-degree relatives of patients with schizophrenia than in the general population. The assessment of schizotypy is primarily based on self-reports, and for this reason it presents several limitations. In order to assess schizotypy, this study proposes a diagnostic instrument based on clinical reports.

Research paper thumbnail of Poster #S43 BRAIN'S FUNCTIONAL ALTERATIONS IN HIGH PERFORMANCE SCHIZOPHRENIC PATIENTS

Schizophrenia Research, 2014

ABSTRACT BACKGROUND: Alterations of both functional activations and functional connectivity in re... more ABSTRACT BACKGROUND: Alterations of both functional activations and functional connectivity in regions of Task Positive Network (TPN) and Default Mode Network (DMN) were reported in studies on cognition of schizophrenic patients. It has been supposed that an impairment of DMN suppression might cause an alteration of task-relevant signal processing, contributing to cognitive deficit of schizophrenic patients. Furthermore, both dorsal attention system and sensorimotor cortex show a hyperactivation in patients without cognitive impairment. Authors speculate that conserved cognitive functions in schizophrenic patients correlate with a compensatory increased activation in these regions. These results suggest an alteration of multiple functional sub-networks in schizophrenic patients during execution of different cognitive tasks. In this study, we want to detect if a better performance in schizophrenic patients is due to: 1) altered connectivity between DMN and TPN, 2) increased activations in compensatory regions, 3) a mixture between these two mechanisms. METHODS: The sample consisted of 9 schizophrenic patients with high task performance (HTP) on Variable Attentional Control (VAC) task, 6 patients with low task performance (LTP) on VAC test and 13 healthy volunteers (HC). fMRI acquisition was performed with a 3 Tesla Siemens scanner in two conditions: event-related modality (efMRI) and resting state. During efMRI all partecipants performed the VAC task. VAC is designed to measure the attentional control increasing conflict detection and allocation of attentional resources within the same stimuli. A repeated measure ANOVA was carried out for behavioral data using SPSS 20. A repeated measure ANOVA was employed for efMRI images using SPM8. Seed-to-voxel analysis, performed with fMRI functional connectivity toolbox, was utilized for resting state images using as seed regions the cluster of the previous analysis and two ROIs for ventral and dorsal DMN. RESULTS: Mixed Designs ANOVA for behavioral data demonstrated a significant effect of cognitive load in both reaction time and rate of correct responses [F(2,48)=17.304 p<0.01; F(2,48)=54.151 p<0.01], a significant group effect [F(2,48)=25.878 p<0.01] in the performance and an interaction between the factors [F(4,48)=9.021 p<0.01]. Post-hoc analysis, confirming the previous subdivision of patients, showed that LTP has lower mean rate of correct responses then both HPT and HC (p<0.01 Bonferroni). The efMRI analysis showed only a significant principal effect of group in left Postcentral Gyrus BA40 [F(2,72)=16.960 p<0.05 FWE-corrected, k=45, coordinates: −56 −24 18]. In particular, there was a greater activation of this region in HTP respect to LPT [T(1,72)=7.24 p<0.05 FWE-corrected, k=80]. The resting state analysis showed a hyperconnectivity of HTP compared to HC in left somatosensorial cortex BA2/3 and left supramarginal gyrus BA40 [T(1,19)=3.58 p<0.01 FDR-corrected, coordinates: 48 −24 44] from seed in postcentral gyrus BA40, while there was an increase of connectivity from dorsal DMN to right dorsal frontal cortex BA8, dorsolateral prefrontal cortex BA9 [T(1,12)=3.93 p<0.05 FDR-corrected, coordinates: −36 38 42] in LTP respect to HTP. DISCUSSION: Our results support both hypotheses, in line with the idea of alterations in different functional sub-networks. We suppose that the dysconnectivity between TPN and DMN in resting state could be a general mark of cognitive impairment in schizophrenic patients, but the nature of a particular task could require different compensatory activations. Future research could clarify the relationship between alteration of DMN-TPN functional connectivity and the development of compensatory alternative strategies.

Research paper thumbnail of Medial frontal gyrus alterations in schizophrenia: Relationship with duration of illness and executive dysfunction

Psychiatry research, Jan 28, 2015

Executive functioning is consistently impaired in schizophrenia, and it has been associated with ... more Executive functioning is consistently impaired in schizophrenia, and it has been associated with reduced gray matter volume in prefrontal areas. Abnormalities in prefrontal brain regions have also been related to the illness duration. The aim of the study was to investigate the effect of executive functioning decline and chronicity in prefrontal regions of patients with schizophrenia. Participants comprised 33 schizophrenic patients, 18 with duration of illness (DoI) shorter than 10 years and 15 with duration of illness longer than 10 years. In addition, 24 healthy controls served as a comparison group. Participants performed the Wisconsin Card Sorting Test (WCST) and underwent structural magnetic resonance imaging. Patients with longer DoI showed significant reduction of gray matter volume in the left medial frontal gyrus compared with healthy controls. Moreover, there was a trend for greater gray matter volume decrease in patients with a longer illness duration compared with patie...

Research paper thumbnail of Schizotypy and personality profiles of Cluster A in a group of schizophrenic patients and their siblings

BMC Psychiatry, 2013

Background: Schizotypy, or the set of personality traits related to schizophrenia, is considered ... more Background: Schizotypy, or the set of personality traits related to schizophrenia, is considered an endophenotypic manifestation that is more represented in first-degree relatives of patients with schizophrenia than in the general population. The assessment of schizotypy is primarily based on self-reports, and for this reason it presents several limitations. In order to assess schizotypy, this study proposes a diagnostic instrument based on clinical reports.

Research paper thumbnail of Poster #S53 MEDIAL FRONTAL GYRUS ALTERATIONS IN SCHIZOPHRENIA: RELATIONSHIP WITH DURATION OF ILLNESS AND EXECUTIVE DYSFUNCTION

Research paper thumbnail of Schizotypy and personality profiles of Cluster A in a group of schizophrenic patients and their siblings

BMC Psychiatry, 2013

Background: Schizotypy, or the set of personality traits related to schizophrenia, is considered ... more Background: Schizotypy, or the set of personality traits related to schizophrenia, is considered an endophenotypic manifestation that is more represented in first-degree relatives of patients with schizophrenia than in the general population. The assessment of schizotypy is primarily based on self-reports, and for this reason it presents several limitations. In order to assess schizotypy, this study proposes a diagnostic instrument based on clinical reports.

Research paper thumbnail of Poster #S43 BRAIN'S FUNCTIONAL ALTERATIONS IN HIGH PERFORMANCE SCHIZOPHRENIC PATIENTS

Schizophrenia Research, 2014

ABSTRACT BACKGROUND: Alterations of both functional activations and functional connectivity in re... more ABSTRACT BACKGROUND: Alterations of both functional activations and functional connectivity in regions of Task Positive Network (TPN) and Default Mode Network (DMN) were reported in studies on cognition of schizophrenic patients. It has been supposed that an impairment of DMN suppression might cause an alteration of task-relevant signal processing, contributing to cognitive deficit of schizophrenic patients. Furthermore, both dorsal attention system and sensorimotor cortex show a hyperactivation in patients without cognitive impairment. Authors speculate that conserved cognitive functions in schizophrenic patients correlate with a compensatory increased activation in these regions. These results suggest an alteration of multiple functional sub-networks in schizophrenic patients during execution of different cognitive tasks. In this study, we want to detect if a better performance in schizophrenic patients is due to: 1) altered connectivity between DMN and TPN, 2) increased activations in compensatory regions, 3) a mixture between these two mechanisms. METHODS: The sample consisted of 9 schizophrenic patients with high task performance (HTP) on Variable Attentional Control (VAC) task, 6 patients with low task performance (LTP) on VAC test and 13 healthy volunteers (HC). fMRI acquisition was performed with a 3 Tesla Siemens scanner in two conditions: event-related modality (efMRI) and resting state. During efMRI all partecipants performed the VAC task. VAC is designed to measure the attentional control increasing conflict detection and allocation of attentional resources within the same stimuli. A repeated measure ANOVA was carried out for behavioral data using SPSS 20. A repeated measure ANOVA was employed for efMRI images using SPM8. Seed-to-voxel analysis, performed with fMRI functional connectivity toolbox, was utilized for resting state images using as seed regions the cluster of the previous analysis and two ROIs for ventral and dorsal DMN. RESULTS: Mixed Designs ANOVA for behavioral data demonstrated a significant effect of cognitive load in both reaction time and rate of correct responses [F(2,48)=17.304 p<0.01; F(2,48)=54.151 p<0.01], a significant group effect [F(2,48)=25.878 p<0.01] in the performance and an interaction between the factors [F(4,48)=9.021 p<0.01]. Post-hoc analysis, confirming the previous subdivision of patients, showed that LTP has lower mean rate of correct responses then both HPT and HC (p<0.01 Bonferroni). The efMRI analysis showed only a significant principal effect of group in left Postcentral Gyrus BA40 [F(2,72)=16.960 p<0.05 FWE-corrected, k=45, coordinates: −56 −24 18]. In particular, there was a greater activation of this region in HTP respect to LPT [T(1,72)=7.24 p<0.05 FWE-corrected, k=80]. The resting state analysis showed a hyperconnectivity of HTP compared to HC in left somatosensorial cortex BA2/3 and left supramarginal gyrus BA40 [T(1,19)=3.58 p<0.01 FDR-corrected, coordinates: 48 −24 44] from seed in postcentral gyrus BA40, while there was an increase of connectivity from dorsal DMN to right dorsal frontal cortex BA8, dorsolateral prefrontal cortex BA9 [T(1,12)=3.93 p<0.05 FDR-corrected, coordinates: −36 38 42] in LTP respect to HTP. DISCUSSION: Our results support both hypotheses, in line with the idea of alterations in different functional sub-networks. We suppose that the dysconnectivity between TPN and DMN in resting state could be a general mark of cognitive impairment in schizophrenic patients, but the nature of a particular task could require different compensatory activations. Future research could clarify the relationship between alteration of DMN-TPN functional connectivity and the development of compensatory alternative strategies.

Research paper thumbnail of Medial frontal gyrus alterations in schizophrenia: Relationship with duration of illness and executive dysfunction

Psychiatry research, Jan 28, 2015

Executive functioning is consistently impaired in schizophrenia, and it has been associated with ... more Executive functioning is consistently impaired in schizophrenia, and it has been associated with reduced gray matter volume in prefrontal areas. Abnormalities in prefrontal brain regions have also been related to the illness duration. The aim of the study was to investigate the effect of executive functioning decline and chronicity in prefrontal regions of patients with schizophrenia. Participants comprised 33 schizophrenic patients, 18 with duration of illness (DoI) shorter than 10 years and 15 with duration of illness longer than 10 years. In addition, 24 healthy controls served as a comparison group. Participants performed the Wisconsin Card Sorting Test (WCST) and underwent structural magnetic resonance imaging. Patients with longer DoI showed significant reduction of gray matter volume in the left medial frontal gyrus compared with healthy controls. Moreover, there was a trend for greater gray matter volume decrease in patients with a longer illness duration compared with patie...