Emotion-elicited gamma synchrony in patients with first-episode schizophrenia: a neural correlate of social cognition outcomes

Background

Schizophrenia may be understood as a disorder of neural synchrony. There is also increasing evidence that emotional and social cognitive impairments are central to this disorder. In patients with first-episode schizophrenia, we examined whether emotion perception is associated with disruptions to high-frequency (40 Hz) gamma synchrony and whether these disruptions predict self-regulatory adaptive compensations reflected in social cognitive behaviours.

Methods

We obtained electroencephalography recordings from 28 patients with first-episode schizophrenia and matched healthy controls during perception of facial emotion under both conscious and nonconscious conditions. We extracted gamma-band synchrony from the electroencephalogram. We also used behavioural measures of emotion identification, emotional intelligence, negativity bias and social function, along with ratings of first-episode schizophrenia symptoms. We analyzed group differences and predicted social cognition to assess the potential contribution of medication.

Results

Within 200 ms poststimulus, patients with first-episode schizophrenia showed alterations in gamma synchrony during both conscious and nonconscious emotion perception. Stimulus-locked synchrony was reduced in patients, particularly over the temporal cortex, whereas complementary enhancements in absolute gamma synchrony (independent of stimuli) were more distributed over temporal and left parieto-occipital regions. This pattern of altered synchrony predicted poor performance on each measure of social cognition among these patients. Medication dosage did not correlate significantly with either gamma synchrony or behavioural measures in this group.

Limitations

Limitations to our study include the lack of comparison between medicated and unmedicated patients or between types of medication.

Conclusion

These findings suggest that disruptions in integrative processing of motivationally important stimuli show promise as a potential biological marker of social cognitive impairments, present from the first episode of schizophrenia, and their outcomes.     

Complementary diffusion tensor imaging study of the corpus callosum in patients with first-episode and chronic schizophrenia

Background

Abnormalities in the corpus callosum have long been implicated in schizophrenia. Previous diffusion tensor imaging (DTI) studies in patients with different durations of schizophrenia yielded inconsistent results. By comparing patients with different durations of schizophrenia, we investigated if white matter abnormalities of the corpus callosum emerge at an early stage in the illness or result from pathological progression.

Methods

We recruited patients with first-episode schizophrenia, patients with chronic schizophrenia and age-, sex-and handedness-matched healthy controls. We used 2 DTI techniques (voxel-based and fibre-tracking DTI) to investigate differences in corpus callosum integrity among the 3 groups.

Results

With both DTI techniques, significantly decreased fractional anisotropy values were identified in the genu of corpus callosum in patients with chronic schizophrenia, but not first-episode schizophrenia, compared with healthy controls.

Limitations

This study was cross-sectional, and the sample size was relatively small.

Conclusion

Abnormalities in the genu of the corpus callosum might be a progressive process in schizophrenia, perhaps related to disease severity and prognosis.     

Hippocampal and caudate volume reductions in antipsychotic-naive first-episode schizophrenia

Background

Enlarged ventricles and reduced hippocampal volume are consistently found in patients with first-episode schizophrenia. Studies investigating brain structure in antipsychotic-naive patients have generally focused on the striatum. In this study, we examined whether ventricular enlargement and hippocampal and caudate volume reductions are morphological traits of antipsychotic-naive first-episode schizophrenia.

Methods

We obtained high-resolution 3-dimensional T₁-weighted magnetic resonance imaging scans for 38 antipsychotic-naive first-episode schizophrenia patients and 43 matched healthy controls by use of a 3-T scanner. We warped the brain images to each other by use of a high-dimensional intersubject registration algorithm. We performed voxel-wise group comparisons with permutation tests. We performed small volume correction for the hippocampus, caudate and ventricles by use of a false discovery rate correction (p < 0.05) to control for multiple comparisons. We derived and analyzed estimates of brain structure volumes. We grouped patients as those with (n = 9) or without (n = 29) any lifetime substance abuse to examine the possible effects of substance abuse.

Results

We found that hippocampal and caudate volumes were decreased in patients with first-episode schizophrenia. We found no ventricular enlargement, differences in global volume or significant associations between tissue volume and duration of untreated illness or psycho-pathology. The hippocampal volume reductions appeared to be influenced by a history of substance abuse. Exploratory analyses indicated reduced volume of the nucleus accumbens in patients with first-episode schizophrenia.

Limitations

This study was not a priori designed to test for differences between schizophrenia patients with or without lifetime substance abuse, and this subgroup was small.

Conclusion

Reductions in hippocampal and caudate volume may constitute morphological traits in antipsychotic-naive first-episode schizophrenia patients. However, the clinical implications of these findings are unclear. Moreover, past substance abuse may accentuate hippocampal volume reduction. Magnetic resonance imaging studies addressing the potential effects of substance abuse in antipsychotic-naive first-episode schizophrenia patients are warranted.     

Event-related potentials and changes of brain rhythm oscillations during working memory activation in patients with first-episode psychosis

Background

Earlier contributions have documented significant changes in sensory, attention-related endogenous event-related potential (ERP) components and θ band oscillatory responses during working memory activation in patients with schizophrenia. In patients with first-episode psychosis, such studies are still scarce and mostly focused on auditory sensory processing. The present study aimed to explore whether subtle deficits of cortical activation are present in these patients before the decline of working memory performance.

Methods

We assessed exogenous and endogenous ERPs and frontal θ event-related synchronization (ERS) in patients with first-episode psychosis and healthy controls who successfully performed an adapted 2-back working memory task, including 2 visual n-back working memory tasks as well as oddball detection and passive fixation tasks.

Results

We included 15 patients with first-episode psychosis and 18 controls in this study. Compared with controls, patients with first-episode psychosis displayed increased latencies of early visual ERPs and phasic θ ERS culmination peak in all conditions. However, they also showed a rapid recruitment of working memory–related neural generators, even in pure attention tasks, as indicated by the decreased N200 latency and increased amplitude of sustained θ ERS in detection compared with controls.

Limitations

Owing to the limited sample size, no distinction was made between patients with first-episode psychosis with positive and negative symptoms. Although we controlled for the global load of neuroleptics, medication effect cannot be totally ruled out.

Conclusion

The present findings support the concept of a blunted electroencephalographic response in patients with first-episode psychosis who recruit the maximum neural generators in simple attention conditions without being able to modulate their brain activation with increased complexity of working memory tasks.     

Predictive Factors of Social Functioning in Patients with Schizophrenia: Exploration for the Best Combination of Variables Using Data Mining

Objective

This study aimed to use data mining to explore the significantly contributing variables to good social functioning in schizophrenia patients.

Methods

The study cohort comprised 67 schizophrenia patients on stable medication. A total of 51 variables (6 demographic data, 3 illness history, 22 social cognition, 16 neurocognition, 4 psychiatric symptoms) were input into a data-mining decision tree using the Answer Tree program to find the pathway for the best social functioning.

Results

Several contributing factors for good social functioning were found. Continuous attention was the strongest contributing factor. Three variables involving best social functioning included good continuous attention, good theory of mind (TOM), and low sensitivity of disgust emotion.

Conclusion

Our results confirmed the mediating roles of social cognition between neurocognition and functional outcomes, and suggested that social cognition can significantly predict social functioning in schizophrenia patients.     

Structural brain correlates of sensorimotor gating in antipsychotic-naive men with first-episode schizophrenia

Background

Prepulse inhibition (PPI) of the startle reflex is modulated by a complex neural network. Prepulse inhibition impairments are found at all stages of schizophrenia. Previous magnetic resonance imaging (MRI) studies suggest that brain correlates of PPI differ between patients with schizophrenia and healthy controls; however, these studies included only patients with chronic illness and medicated patients. Our aim was to examine the structural brain correlates of PPI in antipsychotic-naive patients with first-episode schizophrenia.

Methods

We performed acoustic PPI assessment and structural MRI (1.5 and 3 T) in men with first-episode schizophrenia and age-matched controls. Voxel-based morphometry was used to investigate the association between PPI and grey matter volumes.

Results

We included 27 patients and 38 controls in the study. Patients had lower PPI than controls. The brain areas in which PPI and grey matter volume correlated did not differ between the groups. Independent of group, PPI was significantly and positively associated with regional grey matter volume in the right superior parietal cortex. Prepulse inhibition and grey matter volume associations were also observed in the left rostral dorsal premotor cortex, the right presupplementary motor area and the anterior medial superior frontal gyrus bilaterally. Follow-up analyses suggested that the rostral dorsal premotor cortex and presupplementary motor area correlations were driven predominantly by the controls.

Limitations

We used 2 different MRI scanners, which might have limited our ability to find subcortical associations since interscanner consistency is low for subcortical regions.

Conclusion

The superior parietal cortex seems to be involved in the regulation of PPI in controls and antipsychotic-naive men with first-episode schizophrenia. Our observation that PPI deficits in schizophrenia may be related to the rostral dorsal premotor cortex and presupplementary motor area, brain areas involved in maintaining relevant sensory information and voluntary inhibition, warrants further study.     

Strong subjective recovery as a protective factor against the effects of positive symptoms on quality of life outcomes in schizophrenia

Background

Interest in recovery from schizophrenia has been growing steadily, with much of the focus on remission from psychotic symptoms and a return to functioning. Less is known about the experience of subjective recovery and its relationships with other important outcomes, such as quality of life and the formation and sustenance of social connections. This study sought to address this gap in knowledge by examining the links between self perceived recovery, symptoms, and the social components of quality of life.

Methods

Sixty eight veterans with schizophrenia-spectrum disorders who were participating in a study of cognitive remediation and work were concurrently administered the Recovery Assessment Scale, Positive and Negative Syndrome Scale, and the Heinrichs-Carpenter Quality of Life Scale (QLS).

Results

Linear regression analyses demonstrated that subjective recovery moderated the relationship between positive symptoms and both QLS intrapsychic foundations scores and QLS instrumental role functioning after controlling for negative symptoms. Further examination of this interaction revealed that for individuals with substantial positive symptoms, higher levels of subjective recovery were associated with better instrumental role functioning and intrapsychic foundational abilities.

Conclusion

Greater self perceived recovery is linked with stronger quality of life, both in regards to the cognitive and affective bases for socialization and active community involvement, even in the presence of substantial psychotic symptoms. Clinical implications of these findings are discussed.     

Electroencephalographic Abnormalities and 5-Year Outcome in First-Episode Psychosis

Objective:

To examine the relation of electroencephalographic abnormalities to 5-year outcomes in first-episode psychosis (FEP).

Methods:

Patients (n = 103) had their baseline electroencephalogram (EEG) classified by modified Mayo Clinic criteria. Symptoms and psychosocial functioning were rated after 5 years of treatment.

Results:

Dysrhythmic EEG was associated with persistence in positive and negative symptoms of psychoses and poorer psychosocial functioning at 5-year follow-up, independently of other characteristics, such as duration of untreated illness or premorbid adjustment. A higher percentage of people with comorbid substance use disorder had normal EEG.

Conclusions:

Abnormal baseline EEG in FEP is associated with poorer 5-year symptomatic and functional outcome.     

Role of Visual Integration in Gaze Perception and Emotional Intelligence in Schizophrenia

Background:

Individuals with schizophrenia demonstrate a wide range of social cognitive deficits that significantly compromise functioning. Early visual processing is frequently disrupted in schizophrenia, and growing evidence suggests a role of perceptual dysfunctions in socioemotional functioning in the disorder. This study examined visual integration (the ability to effectively integrate individual, local visual features into a holistic representation), a target construct of basic perception identified by the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia initiative, and its relationship with eye- contact perception and emotional intelligence in schizophrenia.

Methods:

Twenty-nine participants with schizophrenia (SCZ) and 23 healthy controls (HC) completed tasks measuring visual integration (Coherent Motion Task, Contour Integration Task), an eye-contact perception task, and a measure of emotional intelligence.

Results:

SCZ participants showed compromised visual integration as suggested by poorer performance on the Contour Integration Task relative to HC. Visual integration was a significant predictor of eye-contact perception and emotional intelligence among SCZ. The amounts of variances in these 2 social cognitive areas accounted for by visual integration were comparable to and overlapped with those accounted for by the diagnosis of schizophrenia.

Conclusions:

Individuals with schizophrenia showed compromised visual integration, and this may play a significant role in the observed deficits in higher level processing of social information in the disorder.Key words: psychosis, visual perception, perceptual organization, social cognition, sensory processing     

Neuroplasticity-Based Auditory Training Via Laptop Computer Improves Cognition in Young Individuals With Recent Onset Schizophrenia

Objective:

Cognitive deficits that characterize schizophrenia are present in the prodrome, worsen with illness onset, and predict functional outcome. Cognitive dysfunction is thus a critical target for early intervention in young individuals with recent onset schizophrenia.

Method:

This 2-site double-blind randomized controlled trial investigated cognitive training of auditory processing/verbal learning in 86 subjects with recent onset schizophrenia (mean age of 21 years). Subjects were given laptop computers to take home and were asked to perform 40 hours of training or 40 hours of commercial computer games over 8 weeks. We examined cognitive measures recommended by the Measurement and Treatment Research to Improve Cognition in Schizophrenia initiative (MATRICS), symptoms, and functioning. We also assessed baseline reward anticipation to index motivational system functioning and measured changes in auditory processing speed after 20 hours of training to assess target engagement.

Results:

Auditory training subjects demonstrated significant improvements in global cognition, verbal memory, and problem solving compared with those of computer games control subjects. Both groups showed a slight but significant decrease in symptoms and no change in functional outcome measures. Training-induced cognitive gains at posttraining showed significant associations with reward anticipation at baseline and with improvement in auditory processing speed at 20 hours.

Conclusion:

Neuroscience-informed cognitive training via laptop computer represents a promising treatment approach for cognitive dysfunction in early schizophrenia. An individual’s baseline motivational system functioning (reward anticipation), and ability to engage in auditory processing speed improvement, may represent important predictors of treatment outcome. Future studies must investigate whether cognitive training improves functioning and how best to integrate it into critical psychosocial interventions.Key words: cognitive remediation, cognitive training, motivation, first-episode schizophrenia, early psychosis     

Neural correlates of recognition memory of social information in people with schizophrenia

Background

Social dysfunction is a hallmark characteristic of schizophrenia. Part of it may stem from an inability to efficiently encode social information into memory and retrieve it later. This study focused on whether patients with schizophrenia show a memory boost for socially relevant information and engage the same neural network as controls when processing social stimuli that were previously encoded into memory.

Methods

Patients with schizophrenia and healthy controls performed a social and nonsocial picture recognition memory task while being scanned. We calculated memory performance using d′. Our main analysis focused on brain activity associated with recognition memory of social and nonsocial pictures.

Results

Our study included 28 patients with schizophrenia and 26 controls. Healthy controls demonstrated a memory boost for socially relevant information. In contrast, patients with schizophrenia failed to show enhanced recognition sensitivity for social pictures. At the neural level, patients did not engage the dorsomedial prefrontal cortex (DMPFC) as much as controls while recognizing social pictures.

Limitations

Our study did not include direct measures of self-referential processing. All but 3 patients were taking antipsychotic medications, which may have altered both the behavioural performance during the picture recognition memory task and brain activity.

Conclusion

Impaired social memory in patients with schizophrenia may be associated with altered DMPFC activity. A reduction of DMPFC activity may reflect less involvement of self-referential processes during memory retrieval. Our functional MRI results contribute to a better mapping of the neural disturbances associated with social memory impairment in patients with schizophrenia and may facilitate the development of innovative treatments, such as transcranial magnetic stimulation.     

Psychiatric Comorbidity and Quality of Life in Patients with Post-Stroke Emotional Incontinence

Objective

We aimed to investigate the associations of post-stroke emotional incontinence (PSEI) with various psychiatric symptoms and quality of life independent of potential covariates in survivors of acute stroke.

Methods

A total of 423 stroke patients were assessed within 2 weeks of the index event. Psychiatric symptoms were assessed by the Symptom Checklist-90-Revised (SCL-90-R), which has nine domains comprising Somatization, Obsessive-Compulsive, Interpersonal Sensitivity, Depression, Anxiety, Hostility, Phobic Anxiety, Paranoid Ideation, and Psychoticism. Quality of life was measured using the World Health Organization Quality of Life abbreviated form (WHOQOL-BREF), which has four domains related to physical factors, psychological factors, social relationships, and environmental context. Associations of PSEI with scores on the SCL-90-R and WHOQOL-BREF were investigated using pairwise logistic regression model adjustment for potential sociodemographic and clinical covariates.

Results

PSEI was present in 51 (12.1%) patients. PSEI was associated with the Obsessive-Compulsive, Interpersonal Sensitivity, and Hostility symptom dimensions of the SCL-90-R and with the psychological factors and social relationships domains of the WHOQOL-BREF independent of important covariates including previous stroke, stroke severity, and physical disability.

Conclusion

PSEI causes some aspects of psychiatric distress and negatively affects psychological and interpersonal quality of life. For patients with PSEI, special attention to psychiatric comorbidity and quality of life is needed, even in the acute stage of stroke.     

Alterations in White Matter Evident Before the Onset of Psychosis

Background

Psychotic disorders are associated with widespread reductions in white matter (WM) integrity. However, the stage at which these abnormalities first appear and whether they are correlates of psychotic illness, as opposed to an increased vulnerability to psychosis, is unclear. We addressed these issues by using diffusion tensor imaging (DTI) to study subjects at ultra high risk (UHR) of psychosis before and after the onset of illness.

Methods

Thirty-two individuals at UHR for psychosis, 32 controls, and 15 patients with first-episode schizophrenia were studied using DTI. The UHR subjects and controls were re-scanned after 28 months. During this period, 8 UHR subjects had developed schizophrenia. Between-group differences in fractional anisotropy (FA) and diffusivity were evaluated cross sectionally and longitudinally using a nonparametric voxel-based analysis.

Results

At baseline, WM DTI properties were significantly different between the 3 groups (P < .001). Relative to controls, first-episode patients showed widespread reductions in FA and increases in diffusivity. DTI indices in the UHR group were intermediate relative to those in the other 2 groups. Longitudinal analysis revealed a significant group by time interaction in the left frontal WM (P < .001). In this region, there was a progressive reduction in FA in UHR subjects who developed psychosis that was not evident in UHR subjects who did not make a transition.

Conclusions

People at UHR for psychosis show alterations in WM qualitatively similar to, but less severe than, those in patients with schizophrenia. The onset of schizophrenia may be associated with a progressive reduction in the integrity of the frontal WM.     

The Mediating Effects of Self-Esteem and Optimism on the Relationship between Quality of Life and Depressive Symptoms of Breast Cancer Patients

Objective

This study investigated the mediating effects of the internal psychological factors of self-esteem and optimism on the relationship between breast cancer patients'' quality of life in terms of symptoms and functioning and depressive symptoms.

Methods

The study centered on 384 breast cancer patients who had within a 24-month period received diagnosis of 0-4 stage cancer and had medical treatment. To achieve the study''s purpose, the study made use of EORTC QLQ BR23, CES-D, and the Self-Esteem and Optimism Scales.

Results

Findings revealed that breast cancer patients'' quality of life was negatively impacted by self-esteem and optimism, and that self-esteem and optimism impacted negatively on depressive symptoms. Analyses showed that when breast cancer patients'' quality of life affects depressive symptoms, the full mediation effect of self-esteem was statistically significant. Also, findings revealed there to be a significant partial mediation effect due to optimism.

Conclusion

Study findings demonstrated that enhancing self-esteem is crucial in the psychological intervention of depressive symptoms because self-esteem functioned as the main causal factor accounting for all variation when breast cancer patients'' quality of life affected depressive symptoms. In addition, results suggested that optimism is also vital to psychological intervention because it functioned as partial cause of heightened depressive symptoms when breast cancer patients'' quality of life affected depressive symptoms.     

Reduced neural activity of the prefrontal cognitive control circuitry during response inhibition to negative words in people with schizophrenia

Background

Schizophrenia is characterized by deficits in executive control and impairments in emotion processing. This study assessed the nature and extent of potential alterations in the neural substrates supporting the interaction between cognitive control mechanisms and emotion attribution processes in people with schizophrenia.

Methods

Functional magnetic resonance imaging was performed during a verbal emotional go/no-go task. People with schizophrenia and healthy controls responded to word stimuli of a prespecified emotional valence (positive, negative or neutral) while inhibiting responses to stimuli of a different valence.

Results

We enrolled 20 people with schizophrenia and 23 controls in the study. Healthy controls activated an extensive dorsal prefrontal–parietal network while inhibiting responses to negative words compared to neutral words, but showed deactivation of the midcingulate cortex while inhibiting responses to positive words compared to neutral words. People with schizophrenia failed to activate this network during response inhibition to negative words, whereas during response inhibition to positive words they did not deactivate the cingulate, but showed increased responsivity in the frontal cortex.

Limitations

Sample heterogeneity is characteristic of studies of schizophrenia and may have contributed to more variable neural responses in the patient sample despite the care taken to control for potentially confounding variables.

Conclusion

Our results showed that schizophrenia is associated with aberrant modulation of neural responses during the interaction between cognitive control and emotion processing. Failure of the frontal circuitry to regulate goal-directed behaviour based on emotion attributions may contribute to deficits in psychosocial functioning in daily life.     

Nightmares in Patients With Psychosis: The Relation With Sleep,Psychotic, Affective,and Cognitive Symptoms

Objective:

To examine the prevalence of nightmares in people with psychosis and to describe the link between nightmares and sleep quality, psychotic, affective, and cognitive symptoms.

Methods:

Forty participants with psychotic symptoms completed an assessment of nightmares, sleep quality, positive symptoms of psychosis, affect, posttraumatic stress, social functioning, and working memory.

Results:

Among the patients, 55% reported weekly distressing nightmares. Experience of more frequent nightmares was related to poorer sleep quality and sleep efficiency. More distressing nightmares were positively associated with greater delusional severity, depression, anxiety, stress, and difficulties with working memory.

Conclusions:

Nightmares might be common in those with psychosis and are associated with increased day- and nighttime impairment. Future research should investigate treatments for nightmares, for people presenting with psychotic symptoms.     

White Matter Development in Adolescence: Diffusion Tensor Imaging and Meta-Analytic Results

Background

In light of the evidence for brain white matter (WM) abnormalities in schizophrenia, study of normal WM maturation in adolescence may provide critical insights relevant to the neurodevelopment of the disorder. Voxel-wise diffusion tensor imaging (DTI) studies have consistently demonstrated increases in fractional anisotropy (FA), a putative measure of WM integrity, from childhood into adolescence. However, the WM tracts that show FA increases have been variable across studies. Here, we aimed to assess which WM tracts show the most pronounced changes across adolescence.

Methods

DTI was performed in 78 healthy subjects aged 8–21 years, and voxel-wise analysis conducted using tract-based spatial statistics (TBSS). In addition, we performed the first meta-analysis of TBSS studies on WM development in adolescence.

Results

In our sample, we observed bilateral increases in FA with age, which were most significant in the left superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, and anterior thalamic radiation. These findings were confirmed by the meta-analysis, and FA increase in the bilateral SLF was the most consistent finding across studies. Moreover, in our sample, FA of the bilateral SLF showed a positive association with verbal working memory performance and partially mediated increases in verbal fluency as a function of increasing age.

Conclusions

These data highlight increasing connectivity in the SLF during adolescence. In light of evidence for compromised SLF integrity in high-risk and first-episode patients, these data suggest that abnormal maturation of the SLF during adolescence may be a key target in the neurodevelopment of schizophrenia.     

Adjunctive memantine therapy for cognitive impairment in chronic schizophrenia: a placebo-controlled pilot study

Objective

To investigate the effects of memantine, an N-methyl-d-aspartate (NMDA) receptor antagonist, on cognitive impairments in patients with chronic schizophrenia.

Methods

A 12-week, placebo-controlled trial was conducted to determine the effectiveness of memantine as an adjunctive treatment with conventional antipsychotic medications in 26 patients with chronic schizophrenia. The subjects were evaluated with the Korean version of the Mini-Mental State Examination (K-MMSE), the Positive and Negative Syndrome Scale (PANSS), the Hamilton Rating Scale for Depression (HAM-D), and a standard neuropsychological screening test.

Results

Memantine treatment was not associated with significantly improved cognitive test scores compared with the placebo control treatment. An improvement in the scores on the PANSS negative subscale was noted with memantine, but it was not significant.

Conclusion

Adjunctive memantine treatment did not improve cognitive functioning or affect psychopathology in patients with chronic schizophrenia in the present study. Memantine, however, was tolerated well and did not exacerbate positive symptoms in patients with chronic schizophrenia.     

Relation between emotional face memory and social anhedonia in schizophrenia

Background

There is an interest in investigating the relation between emotional memory impairments in schizophrenia and specific symptom dimensions. We explored potential links between emotional memory and social anhedonia severity in patients with schizophrenia and in healthy individuals.

Methods

Twenty-nine patients with schizophrenia and 27 matched healthy individuals completed the Chapman Revised Social Anhedonia Scale and then performed an emotional face recognition memory task involving happy, sad and neutral face expressions. We calculated emotional memory performance using 2 independent measures: the discrimination accuracy index Pr and the response bias Br. We also measured valence ratings of the face stimuli. We performed correlation analyses using the inter-individual variability in social anhedonia severity and the individual score obtained for each memory performance variable and for each face valence rating condition.

Results

Patients with schizophrenia reported higher levels of social anhedonia compared with healthy individuals. They also showed lower recognition accuracy for faces compared with healthy participants. We found no significant correlation between social anhedonia severity and any of the memory performance variables for both patients with schizophrenia and healthy individuals. Regarding potential links between social anhedonia severity and face valence ratings, we found that individuals with elevated social anhedonia had a tendency to rate the face stimuli as more negative.

Limitations

Our negative finding may be partly explained by a lack of statistical power owing to our small patient sample. In addition, our patient sample had unusually high estimated IQ scores, which highlights potential issues regarding the generalization of our findings. Finally, we used a yes–no recognition memory task with a very short retention interval delay.

Conclusion

Our results suggest that social anhedonia is not directly linked to emotional memory deficits and biases and does not interfere with the modulatory effect of positively valenced emotion on memory.     

Polarity of the First Episode and Time to Diagnosis of Bipolar I Disorder

Objective

The current study explored the relationship between the polarity of the first episode and the timing of eventual diagnosis of bipolar I disorder, and associated clinical implications.

Methods

Twelve years of clinical data from the medical records of 258 inpatients meeting DSM-III-R or DSM-IV criteria for bipolar I disorder were analyzed. Subjects were divided into two groups according to the polarity of the first episode: those with depressive polarity (FE-D), and those with manic polarity (FE-M). Comparisons were made between the two groups on variables associated with the timing of diagnosis and related outcomes.

Results

In population with bipolar I disorder, a significant longer time lapse from the first major mood episode to the confirmed diagnosis was associated with the FE-D group compared to the FE-M group [5.6 (±6.1) vs. 2.5 (±5.5) years, p<0.001]. FE-D subjects tended to have prior diagnoses of schizophrenia and major depressive disorder while FE-M subjects tended to have prior diagnoses of bipolar disorder and schizophrenia. A significantly higher rate of suicide attempts was associated with the FE-D group compared to the FE-M group (12.7 vs. 1.7%, p<0.001).

Conclusion

The results of this study indicate that first-episode depressive polarity is likely to be followed by a considerable delay until an eventual confirmed diagnosis of bipolar I disorder. Given that first-episode depressive patients are particularly vulnerable to unfavorable clinical outcomes such as suicide attempts, a more systematic approach is needed to differentiate bipolar disorder among depressed patients in their early stages.