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1.
BMC Psychol ; 8(1): 28, 2020 Mar 29.
Article in English | MEDLINE | ID: mdl-32223756

ABSTRACT

BACKGROUND: Individuals tend to have an optimism bias, processing desirable information more frequently than undesirable information. However, people who have been diagnosed with depression often have a more pessimistic view of the future. A recent study suggests that future expectations in individuals with dysphoria become more optimistic when asked to make optimistic future predictions about the future. In the present study, we investigated the differential effects of induced optimism training which making optimistic future prediction to change future beliefs in normal participants with various levels of dysphoria (low, mild, high). METHODS: We recruited normal participants (n = 69) from a local university students and divided participants into three groups (low, mild, high dysphoria) by measuring dysphoric mood. These three groups were assigned to the induced optimism training or control condition. After the training, participants performed the two-stage belief updating task. In the first stage, participants estimated their personal probability of experiencing adverse events while being presented with the average probability of the event occurring to a living person. This information could be desirable for participants(when presented with a probability that was below their estimation) or undesirable (when presented with a probability that was above their estimation). To assess how desirable versus undesirable information influenced beliefs, participants estimated their personal probability of experiencing the events again in the second stage. The amount of update error was calculated as the difference between the estimates in the first stage and the second stage. The difference between the errors was classified as the update bias. RESULTS: After the induced optimism training, individuals with the mild dysphoria demonstrated a higher update bias than low (p < .001) and the high dysphoria (p < .05) group in induced optimism condition. Significant differences were not found in control group. Results indicates that individuals in the mild dysphoria group showed an increased update bias after being exposed to the induced optimism training Dysphoric mood and trait optimism remained unchanged in both the experimental and control groups. CONCLUSIONS: Results suggest that induced optimism training has potential to change individuals with mild dysphoria perceptions' about the future.


Subject(s)
Depression/therapy , Optimism/psychology , Adolescent , Depression/psychology , Female , Humans , Male , Psychotherapy/methods , Young Adult
2.
BMC Psychiatry ; 17(1): 27, 2017 01 18.
Article in English | MEDLINE | ID: mdl-28100219

ABSTRACT

BACKGROUND: Amygdala hyper-reactivity is sometimes assumed to be a vulnerability factor that predates depression; however, in healthy people, who experience early life stress but do not become depressed, it may represent a resilience mechanism. We aimed to test these hypothesis examining whether increased amygdala activity in association with a history of early life stress (ELS) was negatively or positively associated with depressive symptoms and impact of negative life event stress in never-depressed adults. METHODS: Twenty-four healthy participants completed an individually tailored negative mood induction task during functional magnetic resonance imaging (fMRI) assessment along with evaluation of ELS. RESULTS: Mood change and amygdala reactivity were increased in never-depressed participants who reported ELS compared to participants who reported no ELS. Yet, increased amygdala reactivity lowered effects of ELS on depressive symptoms and negative life events stress. Amygdala reactivity also had positive functional connectivity with the bilateral DLPFC, motor cortex and striatum in people with ELS during sad memory recall. CONCLUSIONS: Increased amygdala activity in those with ELS was associated with decreased symptoms and increased neural features, consistent with emotion regulation, suggesting that preservation of robust amygdala reactions may reflect a stress buffering or resilience enhancing factor against depression and negative stressful events.


Subject(s)
Amygdala/physiopathology , Life Change Events , Resilience, Psychological , Stress, Psychological/physiopathology , Adult , Affect/physiology , Affective Symptoms/physiopathology , Affective Symptoms/psychology , Amygdala/diagnostic imaging , Depression/physiopathology , Depression/psychology , Female , Healthy Volunteers , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Stress, Psychological/psychology , Young Adult
3.
J Affect Disord ; 208: 610-614, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-27810274

ABSTRACT

BACKGROUND: Depression is characterized by negative self-cognition. Our previous study (Yoshimura et al. 2014) revealed changes in brain activity after cognitive behavioral therapy (CBT) for depression, but changes in functional connectivity were not assessed. METHOD: This study included 29 depressive patients and 15 healthy control participants. Functional Magnetic Resonance Imaging was used to investigate possible CBT-related functional connectivity changes associated with negative emotional self-referential processing. Depressed and healthy participants (overlapping with our previous study, Yoshimura et al. 2014) were included. We defined a seed region (medial prefrontal cortex) and coupled region (ACC) based on our previous study, and we examined changes in MPFC-ACC functional connectivity from pretreatment to posttreatment. RESULTS: CBT was associated with reduced functional connectivity between the MPFC and ACC. Symptom change with CBT was positively correlated with change in MPFC-ACC functional connectivity. LIMITATIONS: Patients received pharmacotherapy including antidepressant. The present sample size was quite small and more study is needed. Statistical threshold in fMRI analysis was relatively liberal. CONCLUSIONS: CBT for depression may disrupt MPFC-ACC connectivity, with associated improvements in depressive symptoms and dysfunctional cognition.


Subject(s)
Cognitive Behavioral Therapy/methods , Depression/therapy , Gyrus Cinguli/physiopathology , Prefrontal Cortex/physiopathology , Adult , Case-Control Studies , Cognition , Female , Gyrus Cinguli/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , Prefrontal Cortex/diagnostic imaging , Young Adult
4.
Psychiatry Clin Neurosci ; 69(12): 763-72, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26129835

ABSTRACT

AIMS: Somatoform pain disorder is associated with psychosocial dysfunction, and psychotherapies, such as cognitive behavioral therapy (CBT), are thought to provide useful interventions to address such dysfunction as well as the pain itself. However, little is known about whether CBT for somatoform pain disorder is effective, including the long-term course of the illness, in non-Western populations. We therefore tailored such a program based on an existing CBT protocol and examined its effectiveness in Japan. METHODS: Thirty-four Japanese participants (22 women; mean age = 52.5 years) enrolled in a weekly 12-session group treatment, with 32 completing both wait-list and treatment conditions. The primary outcome measure was pain intensity. Secondary outcome measures included pain characteristics, as measured by pain catastrophizing and psychometric evaluations, including depression, anxiety, and quality of life. The patients were followed up for 12 months after treatment. RESULTS: We found that pain intensity, anxiety, depressive symptoms, and social functioning all significantly improved after treatment compared with the wait-list period, and the improvements in pain intensity, depressive symptoms, and social functioning were sustained at 12 months following the completion of CBT. There were strong positive correlations (P < 0.01) among pre- and post-treatment changes in the affective dimension of pain, depression, anxiety, and pain catastrophizing. CONCLUSIONS: These results show that the present CBT program was effective for Japanese patients with somatoform pain disorder and that gains were maintained over the long term. More work is needed to further clarify the effects of CBT interventions on somatoform symptoms, particularly in Japan.


Subject(s)
Anxiety/therapy , Catastrophization/therapy , Cognitive Behavioral Therapy/methods , Depression/therapy , Psychotherapy, Group/methods , Somatoform Disorders/therapy , Adult , Aged , Anxiety/psychology , Catastrophization/psychology , Depression/psychology , Female , Humans , Japan , Male , Middle Aged , Pain Management/methods , Somatoform Disorders/psychology , Treatment Outcome
5.
PLoS One ; 10(5): e0123524, 2015.
Article in English | MEDLINE | ID: mdl-25932629

ABSTRACT

Diagnosis of psychiatric disorders based on brain imaging data is highly desirable in clinical applications. However, a common problem in applying machine learning algorithms is that the number of imaging data dimensions often greatly exceeds the number of available training samples. Furthermore, interpretability of the learned classifier with respect to brain function and anatomy is an important, but non-trivial issue. We propose the use of logistic regression with a least absolute shrinkage and selection operator (LASSO) to capture the most critical input features. In particular, we consider application of group LASSO to select brain areas relevant to diagnosis. An additional advantage of LASSO is its probabilistic output, which allows evaluation of diagnosis certainty. To verify our approach, we obtained semantic and phonological verbal fluency fMRI data from 31 depression patients and 31 control subjects, and compared the performances of group LASSO (gLASSO), and sparse group LASSO (sgLASSO) to those of standard LASSO (sLASSO), Support Vector Machine (SVM), and Random Forest. Over 90% classification accuracy was achieved with gLASSO, sgLASSO, as well as SVM; however, in contrast to SVM, LASSO approaches allow for identification of the most discriminative weights and estimation of prediction reliability. Semantic task data revealed contributions to the classification from left precuneus, left precentral gyrus, left inferior frontal cortex (pars triangularis), and left cerebellum (c rus1). Weights for the phonological task indicated contributions from left inferior frontal operculum, left post central gyrus, left insula, left middle frontal cortex, bilateral middle temporal cortices, bilateral precuneus, left inferior frontal cortex (pars triangularis), and left precentral gyrus. The distribution of normalized odds ratios further showed, that predictions with absolute odds ratios higher than 0.2 could be regarded as certain.


Subject(s)
Algorithms , Depression/diagnosis , Depression/physiopathology , Magnetic Resonance Imaging , Models, Statistical , Adult , Behavior , Discrimination, Psychological , Female , Humans , Likelihood Functions , Logistic Models , Male , Middle Aged , Reproducibility of Results , Semantics , Support Vector Machine , Task Performance and Analysis , Young Adult
6.
PLoS One ; 10(5): e0127426, 2015.
Article in English | MEDLINE | ID: mdl-26000902

ABSTRACT

Social anxiety is characterized by an excessive fear of being embarrassed in social interactions or social performance situations. Emotional support can help to decrease or diminish social distress. Such support may play an important role at different points of social interaction. However, it is unclear how the beneficial effects of social support are represented in the brains of socially anxious individuals. To explore this, we used the same paradigm previously used to examine the effects of emotional support on social pain caused by exclusion. Undergraduates (n = 46) showing a wide range of social anxiety scores underwent functional magnetic resonance imaging (fMRI) while participating in a Cyberball game. Participants were initially included and later excluded from the game. In the latter half of the session in which participants were excluded, they were provided with supportive messages. In line with our previous work, we found that social exclusion led to increased anterior cingulate cortex (ACC) activity, whereas emotional support led to increased left dorsolateral prefrontal cortex (DLPFC) activity. Despite validation of the paradigm, social anxiety was not associated with increased ACC activity during social exclusion, or during perceived emotional support. Instead, fear of negative evaluation as assessed by the Brief Fear of Negative Evaluation (BFNE) scale showed positive associations with left DLPFC activation while receiving emotional support, compared to while being socially excluded. The more socially anxious an individual was, the greater was the left DLPFC activity increased during receipt of messages. This suggests that highly socially anxious people still have the ability to perceive social support, but that they are nevertheless susceptible to negative evaluation by others.


Subject(s)
Brain/physiopathology , Emotions/physiology , Phobic Disorders/physiopathology , Social Isolation/psychology , Social Support , Anxiety/physiopathology , Anxiety/psychology , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Phobic Disorders/psychology , Young Adult
7.
Neurosci Lett ; 581: 109-14, 2014 Oct 03.
Article in English | MEDLINE | ID: mdl-25168605

ABSTRACT

Functional MRI (fMRI) studies have been used to investigate how the brain processes noxious stimuli in osteoarthritis (OA) and to identify the cortical location of pain perception. However, no consensus has been reached regarding brain activity associated with pain-induced conditions in OA patients. We examined cerebral responses using intra-epidermal electrical stimulation of the . knee in knee OA patients. To replicate the pain of knee OA in terms of predictability, acute pain generated by electrical stimulation was provided simultaneously with displayed images in this study. We used fMRI to identify differences in response between healthy subjects and knee OA patients and explored the modulating cortico-subcortical and cortico-cortical pathways using psychophysiological interaction (PPI) analysis. Our results show that chronic pain results in a different brain activation profile in the DLPFC and the pain matrix in knee OA patients. Abnormal brain connectivity between the DLPFC and the pain matrix is induced by chronic pain in knee OA patients.


Subject(s)
Nerve Net/physiopathology , Osteoarthritis, Knee/physiopathology , Pain Perception/physiology , Prefrontal Cortex/physiopathology , Aged , Brain/physiopathology , Brain Mapping , Electric Stimulation , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged
8.
J Affect Disord ; 168: 229-35, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25064808

ABSTRACT

BACKGROUND: A recent meta-analysis of many magnetic resonance imaging (MRI) studies has identified brain regions with gray matter (GM) abnormalities in patients with major depressive disorder (MDD). A few studies addressing GM abnormalities in patients with treatment-resistant depression (TRD) have yielded inconsistent results. Moreover, although TRD patients tend to exhibit ruminative thoughts, it remains unclear whether rumination is related to GM abnormalities in such patients or not. METHODS: We conducted structural MRI scans and voxel-based morphometry (VBM) to identify GM differences among 29 TRD patients and 29 healthy age-matched and sex-matched controls. A response style questionnaire was used to assess the respective degrees of rumination in TRD patients. Structural correlates of rumination were examined. RESULTS: TRD patients showed several regions with smaller GM volume than in healthy subjects: the left dorsal anterior cingulate cortex (ACC), right ventral ACC, right superior frontal gyrus, right cerebellum (Crus I), and cerebellar vermis. GM volumes in these regions did not correlate to rumination. However, whole-brain analysis revealed that rumination was positively correlated with the GM volume in the right superior temporal gyrus in TRD patients. LIMITATIONS: Structural correlates of rumination were examined only in TRD patients. CONCLUSIONS: Our data provide additional evidence supporting the hypothesis that TRD patients show GM abnormalities compared with healthy subjects. Furthermore, this report is the first to describe a study identifying brain regions for which the GM volume is correlated with rumination in TRD patients. These results improve our understanding of the anatomical characteristics of TRD.


Subject(s)
Depressive Disorder, Major/pathology , Depressive Disorder, Major/psychology , Gray Matter/abnormalities , Magnetic Resonance Imaging , Thinking , Adult , Brain/abnormalities , Cerebellum/abnormalities , Depressive Disorder, Treatment-Resistant , Female , Gyrus Cinguli/abnormalities , Humans , Male , Middle Aged
9.
PLoS One ; 9(7): e102836, 2014.
Article in English | MEDLINE | ID: mdl-25048028

ABSTRACT

Reappraisal is a well-known emotion regulation strategy. Recent neuroimaging studies suggest that reappraisal recruits both medial and lateral prefrontal brain regions. However, few studies have investigated neural representation of reappraisals associated with anticipatory anxiety, and the specific nature of the brain activity underlying this process remains unclear. We used functional magnetic resonance imaging (fMRI) to investigate neural activity associated with reappraisals of transient anticipatory anxiety. Although transient anxiety activated mainly subcortical regions, reappraisals targeting the anxiety were associated with increased activity in the medial and lateral prefrontal regions (including the orbitofrontal and anterior cingulate cortices). Reappraisal decreased fear circuit activity (including the amygdala and thalamus). Correlational analysis demonstrated that reductions in subjective anxiety associated with reappraisal were correlated with orbitofrontal and anterior cingulate cortex activation. Reappraisal recruits medial and lateral prefrontal regions; particularly the orbitofrontal and anterior cingulate cortices are associated with successful use of this emotion regulation strategy.


Subject(s)
Anticipation, Psychological/physiology , Anxiety/physiopathology , Brain/physiopathology , Emotions/physiology , Adult , Brain Mapping , Female , Functional Neuroimaging , Humans , Magnetic Resonance Imaging , Male , Young Adult
10.
Neurosci Res ; 79: 61-6, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24512703

ABSTRACT

Neuroimaging studies have investigated differences in neural correlates between abstract and concrete concepts but this has not been done with Japanese participants. Concrete words have higher imageability than abstract words, such that they elicit more visual imagery. The present study used functional MRI to investigate brain activity of Japanese participants (N=16) during generation of visual images for written concrete or abstract Japanese kanji words. Concrete words elicited significantly more activation than abstract words in the left middle frontal gyrus (LMFG), bilateral superior frontal gyrus, and left fusiform gyrus (LFG). Psychophysiological interaction (PPI) analyses were performed to assess LMFG and LFG functional connections. LMFG activity was accompanied by increased functional interaction with the left superior parietal lobule (LSPL), and LFG activity was accompanied by increased functional interaction with the LMFG. This finding suggests that the LMFG plays an important role in visual imagery, with interactions between this region and both the LSPL and LFG.


Subject(s)
Brain/physiology , Imagination/physiology , Reading , Adult , Asian People , Brain Mapping , Humans , Japan , Magnetic Resonance Imaging , Male , Semantics , Young Adult
11.
12.
J Affect Disord ; 152-154: 462-7, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24035490

ABSTRACT

BACKGROUND: Altered emotional memory is one of the core cognitive functions that causes and maintains depression. Although many studies have investigated the relationship between hippocampal volume, depression and treatment response, no studies have investigated the relationship for hippocampal activity. Additionally, few studies have examined the relationship between functional and structural abnormalities in depression. METHODS: We conducted a functional and volumetric MRI study investigating associative encoding of positive, negative and neutral word pairs in 13 healthy controls, and 14 untreated depressives. We carried out fMRI during a memory-encoding task at baseline. Treatment response was clinically assessed six weeks after pharmacotherapy began. Then, we explored the relation between brain activation during encoding of each word pair and symptomatic improvement. RESULTS: Relative to controls, depressives exhibited decreased activity in the left hippocampus during encoding positive word pairs and, in contrast, increased activity in the right hippocampus during encoding negative or neutral word pairs. Poor response to treatment was associated with smaller activation within the left hippocampus during the memory encoding of positive word pairs. Overall results were not confounded by hippocampal volume. LIMITATIONS: We could not appreciate any disease alteration during the retrieving phase. CONCLUSION: We found qualitative differences in hippocampus functioning between depressives and healthy controls. In addition, the left hippocampus could have an effect on treatment response in depression by contributing to the dysfunctional encoding of positive information.


Subject(s)
Depressive Disorder, Major/physiopathology , Functional Neuroimaging , Hippocampus/physiopathology , Magnetic Resonance Imaging , Adult , Antidepressive Agents/therapeutic use , Association Learning , Case-Control Studies , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/pathology , Female , Hippocampus/pathology , Humans , Male , Memory , Remission Induction
13.
Soc Cogn Affect Neurosci ; 9(4): 487-93, 2014 Apr.
Article in English | MEDLINE | ID: mdl-23327934

ABSTRACT

Cognitive behavioral therapy (CBT), an effective treatment for depression, targets self-referential processing of emotional stimuli. We examined the effects of CBT on brain functioning during self-referential processing in depressive patients using functional magnetic resonance imaging (fMRI). Depressive patients (n = 23) and healthy participants (n = 15) underwent fMRI scans during a self-referential task using emotional trait words. The depressive patients had fMRI scans before and after completing a total of 12 weekly sessions of group CBT for depression, whereas the healthy participants underwent fMRI scans 12 weeks apart with no intervention. Before undergoing CBT, the depressive patients showed hyperactivity in the medial prefrontal cortex (MPFC) during self-referential processing of negative words. Following CBT, MPFC and ventral anterior cingulate cortex (vACC) activity during self-referential processing among depressive patients was increased for positive stimuli, whereas it was decreased for negative stimuli. Improvements in depressive symptoms were negatively correlated with vACC activity during self-referential processing of negative stimuli. These results suggest that CBT-related improvements in depressive symptoms are associated with changes in MPFC and vACC activation during self-referential processing of emotional stimuli.


Subject(s)
Cognitive Behavioral Therapy/methods , Depression/rehabilitation , Gyrus Cinguli/blood supply , Prefrontal Cortex/blood supply , Self Report , Adult , Analysis of Variance , Depression/pathology , Female , Follow-Up Studies , Humans , Image Processing, Computer-Assisted , Judgment , Magnetic Resonance Imaging , Male , Middle Aged , Oxygen/blood , Psychiatric Status Rating Scales , Time Factors , Treatment Outcome
14.
Neuroimage Clin ; 2: 782-9, 2013.
Article in English | MEDLINE | ID: mdl-24179828

ABSTRACT

Pain is a multidimensional phenomenon. Patients with somatoform pain disorder suffer from long-lasting pain, with the pathology being closely associated with cognitive-emotional components. Differences between these patients and controls in cerebral responses to pain stimuli have been reported. However, to our knowledge, no studies of somatoform pain disorder have evaluated altered pain-related brain activation as modulated by emotional dysregulation. We examined the distinct neural mechanism that is engaged in response to two different pain intensities in a sad emotional condition, performing functional magnetic resonance imaging (fMRI) on a group of 11 somatoform pain patients and an age-matched control group. Our results showed that the ratio for low-pain intensity ratings between the sad and neutral conditions in patients was higher than in controls. They also showed significant increased activation in the anterior/posterior insula in the low pain sadness condition. Furthermore, there was specific functional connectivity between the anterior insula and the parahippocampus in patients during presentation of low-pain stimuli in the sad context. These findings suggest that a negative emotional context such as sadness contributes to dysfunctional pain processing in somatoform pain disorder. Greater sensitivity to low levels of pain in an emotional context of sadness might be an important aspect of the psychopathology of somatoform pain disorder.

15.
Front Hum Neurosci ; 7: 339, 2013.
Article in English | MEDLINE | ID: mdl-23840186

ABSTRACT

Early life stress (ELS), an important risk factor for psychopathology in mental disorders, is associated neuronally with decreased functional connectivity within the default mode network (DMN) in the resting state. Moreover, it is linked with greater deactivation in DMN during a working memory task. Although DMN shows large amplitudes of very low-frequency oscillations (VLFO) and strong involvement during self-oriented tasks, these features' relation to ELS remains unclear. Therefore, our preliminary study investigated the relationship between ELS and the degree of frontal activations during a resting state and self-oriented task using near-infrared spectroscopy (NIRS). From 22 healthy participants, regional hemodynamic changes in 43 front-temporal channels were recorded during 5 min resting states, and execution of a self-oriented task (color-preference judgment) and a control task (color-similarity judgment). Using a child abuse and trauma scale, ELS was quantified. We observed that ELS showed a negative correlation with medial prefrontal cortex (MPFC) activation during both resting state and color-preference judgment. In contrast, no significant correlation was found between ELS and MPFC activation during color-similarity judgment. Additionally, we observed that ELS and the MPFC activation during color-preference judgment were associated behaviorally with the rate of similar color choice in preference judgment, which suggests that, for participants with higher ELS, decisions in the color-preference judgment were based on an external criterion (color similarity) rather than an internal criterion (subjective preference). Taken together, our neuronal and behavioral findings show that high ELS is related to lower MPFC activation during both rest and self-oriented tasks. This is behaviorally manifest in an abnormal shift from internally to externally guided decision making, even under circumstances where internal guidance is required.

16.
Front Syst Neurosci ; 7: 115, 2013.
Article in English | MEDLINE | ID: mdl-24381545

ABSTRACT

Harm avoidance (HA) and novelty seeking (NS) are temperament dimensions defined by Temperament and Character Inventory (TCI), respectively, reflecting a heritable bias for intense response to aversive stimuli or for excitement in response to novel stimuli. High HA is regarded as a risk factor for major depressive disorder and anxiety disorder. In contrast, higher NS is linked to increased risk for substance abuse and pathological gambling disorder. A growing body of evidence suggests that patients with these disorders show abnormality in the power of slow oscillations of resting-state brain activity. It is particularly interesting that previous studies have demonstrated that resting state activities in medial prefrontal cortex (MPFC) are associated with HA or NS scores, although the relation between the power of resting state slow oscillations and these temperament dimensions remains poorly elucidated. This preliminary study investigated the biological bases of these temperament traits by particularly addressing the resting state low-frequency fluctuations in MPFC. Regional hemodynamic changes in channels covering MPFC during 5-min resting states were measured from 22 healthy participants using near-infrared spectroscopy (NIRS). These data were used for correlation analyses. Results show that the power of slow oscillations during resting state around the dorsal part of MPFC is negatively correlated with the HA score. In contrast, NS was positively correlated with the power of resting state slow oscillations around the ventral part of MPFC. These results suggest that the powers of slow oscillation at rest in dorsal or ventral MPFC, respectively, reflect the degrees of HA and NS. This exploratory study therefore uncovers novel neural bases of HA and NS. We discuss a neural mechanism underlying aversion-related and reward-related processing based on results obtained from this study.

17.
Percept Mot Skills ; 115(2): 349-59, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23265001

ABSTRACT

Functional magnetic resonance imaging (fMRI) was used to investigate brain activation associated with a facial expression identification task (stimuli were full emotional, half emotional, or ambiguous in both happy and sad context) in 10 men and 10 women, fMRI assessment revealed significant interaction of sex x context in the right putamen for the ambiguous faces. Women showed a greater BOLD response to ambiguous facial expression in the sad context than in the happy context, while men showed a greater response in the happy context. Further, women showed a greater BOLD response than did men to ambiguous facial expression in the sad context, while men showed a greater response than women in the happy context. These results suggest that sad and happy context differentially modulate right putamen activation related to processing of ambiguous facial expression in men and women.


Subject(s)
Brain/physiology , Facial Expression , Happiness , Neurons/metabolism , Adult , Brain Mapping/methods , Emotions/physiology , Female , Humans , Magnetic Resonance Imaging/methods , Male , Pattern Recognition, Visual/physiology , Sex Factors , Task Performance and Analysis , Young Adult
18.
J Behav Ther Exp Psychiatry ; 43(4): 1088-94, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22721601

ABSTRACT

BACKGROUND AND OBJECTIVES: Depression is characterized by low reward sensitivity in behavioral studies applying signal detection theory. We examined deficits in reward-based decision making in depressed participants during a probabilistic learning task, and used a reinforcement learning model to examine learning parameters during the task. METHODS: Thirty-six nonclinical undergraduates completed a probabilistic selection task. Participants were divided into depressed and non-depressed groups based on Center for Epidemiologic Studies-Depression (CES-D) cut scores. We then applied a reinforcement learning model to every participant's behavioral data. RESULTS: Depressed participants showed a reward-based decision making deficit and higher levels of the learning parameter τ, which modulates variability of action selection, as compared to non-depressed participants. Highly variable action selection is more random and characterized by difficulties with selecting a specific course of action. CONCLUSION: These results suggest that depression is characterized by deficits in reward-based decision making as well as high variability in terms of action selection.


Subject(s)
Decision Making , Depression/psychology , Depressive Disorder/psychology , Probability Learning , Reinforcement, Psychology , Female , Humans , Male , Reward , Young Adult
19.
J Pain ; 13(7): 628-35, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22515946

ABSTRACT

UNLABELLED: Pain is a multidimensional phenomenon. Previous psychological studies have shown that a person's subjective pain threshold can change when certain emotions are recognized. We examined this association with magnetoencephalography. Magnetic field strength was recorded with a 306-channel neuromagnetometer while 19 healthy subjects (7 female, 12 male; age range = 20-30 years) experienced pain stimuli in different emotional contexts induced by the presentation of sad, happy, or neutral facial stimuli. Subjects also rated their subjective pain intensity. We hypothesized that pain stimuli were affected by sadness induced by facial recognition. We found: 1) the intensity of subjective pain ratings increased in the sad emotional context compared to the happy and the neutral contexts, and 2) event-related desynchronization of lower beta bands in the right hemisphere after pain stimuli was larger in the sad emotional condition than in the happy emotional condition. Previous studies have shown that event-related desynchronization in these bands could be consistently observed over the primary somatosensory cortex. These findings suggest that sadness can modulate neural responses to pain stimuli, and that brain processing of pain stimuli had already been affected, at the level of the primary somatosensory cortex, which is critical for sensory processing of pain. PERSPECTIVE: We found that subjective pain ratings and cortical beta rhythms after pain stimuli are influenced by the sad emotional context. These results may contribute to understanding the broader relationship between pain and negative emotion.


Subject(s)
Emotions/physiology , Pain Perception/physiology , Pain/psychology , Somatosensory Cortex/physiopathology , Adult , Brain Mapping , Facial Expression , Female , Humans , Magnetoencephalography , Male , Pain/physiopathology , Pain Measurement/psychology , Pain Threshold/physiology , Physical Stimulation
20.
Hiroshima J Med Sci ; 61(4): 75-83, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23342824

ABSTRACT

Aripiprazole is a D2 and D3 receptor partial agonist that is unlike other second generation antipsychotics. The effectiveness of aripiprazole with regard to neurocognitive function and its adverse effects is unclear. The present study evaluates the comparative efficacy, effects on neurocognitive function, and adverse effects of aripiprazole and risperidone in the treatment of hospitalized patients with schizophrenia. This double-blind, cross-over study included 23 patients with schizophrenia who were randomly assigned to be treated first with either aripiprazole or risperidone. After eight weeks on one medication, the patients were switched to the other medication for eight weeks. The patient assessment included the Positive and Negative Syndrome Scale (PANSS), neurocognitive assessments, and adverse events including extrapyramidal symptoms, vital signs, electrocardiogram, and clinical laboratory tests. The study findings indicated that psychopathology assessed with the PANSS, extrapyramidal symptoms and other adverse effects did not differ between aripiprazole and risperidone for the subjects remaining in treatment. In the neurocognitive assessments, the score for disinhibition with aripiprazole was significantly lower than with risperidone (p < 0.05). In addition, serum prolactin levels were significantly lower with aripiprazole (p < 0.001). The treatment drop-out rate was higher for patients receiving aripiprazole than risperidone. In comparing aripiprazole and risperidone, risperidone is better from the viewpoint of treatment continuation. On the other hand, some adverse effects, such as hyperprolactinemia and disinhibition, are less severe with aripiprazole. Thus, for certain applications, aripiprazole may be a beneficial new treatment option for schizophrenia.


Subject(s)
Antipsychotic Agents/therapeutic use , Cognition/drug effects , Piperazines/therapeutic use , Quinolones/therapeutic use , Risperidone/therapeutic use , Schizophrenia/drug therapy , Adult , Aripiprazole , Cross-Over Studies , Double-Blind Method , Female , Humans , Male , Middle Aged
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