The Gravity Of The Recognition Of Dynamic Facial Expressions In Depressed Patients Before And After Treatment Functional Magnetic Resonance Imaging Study

BackgroundMood disorders are associated with abnormalities in the way emotional stimuli are perceived and responded to.Patients with depression exist in obvious dysfunctional cognition which assume negatively oneself,the world and the future.Compared with healthy controls,individuals diagnosed with depressive disorder exhibit decreased accuracy of recognizing facial expressions,biased interpretation of facial expressions and diminished emotional reactions in response to happy facial expressions.These impairments and biases in the processing of emotional and social stimuli may underlie problems in mood and interpersonal behavior,and contribute to the onset and maintenance of mood disorders.For these reasons,understanding the mechanisms of the emotion processing abnormalities and identifying brain functional correlates of antidepressant treatment may prove to be helpful in the diagnosis,treatment,and prevention of mood disorders.Experiment 1:Neural substrates for explicit recognition of dynamic facial expressions in major depressed patients:a functional magnetic resonance studyObjective:To map brain systems activated by explicit recognition of dynamic facial expression videos in major depressed patients using event-related functional magnetic resonance imaging. Methods:35 Chinese right-handed patients with major depression and 25 volunteers underwent blood oxygen level dependent(BOLD) fMRI while recognizing happy,sad and neutral emotional faces videos. Healthy individuals were matched for age,sex and educational levels with major depression,and negative family history.When examined by fMRI,all subjects were assessed by Wisconsin Card Sorting Test (WCST).Results:1.In comparison with healthy comparison participants,major depression showed increased activation in left Precuneus(BA7),left dorsal posterior Cingulate Gyrus(BA31),right ventral anterior Cingulate Gyrus(BA24)and decreased activation in left Superior Temporal Gyrus(BA38),right Supramarginal Gyrus(BA40),right Middle Occipital Gyrus(BA18),left Inferior Frontal Gyrus(BA47),right Amygdala,right Parahippocampal Gyrus(BA34),right Posterior Cingulate(BA29)and right Putamen in recognition of happy faces.2.In comparison with healthy comparison participants,major depression showed increased activation in right Medial Frontal Gyrus(BA6),left Medial Frontal Gyrus(BA10),right Posterior Cingulate (BA29),right Precuneus(BA7)and left Superior Temporal Gyrus(BA22); and decreased activation in right Middle Frontal Gyrus(BA47),left Inferior Frontal Gyrus(BA47)and right Fusiform Gyrus(BA19)in recognition of sad faces.Conclusion:This study indicates that the neural correlates of major depression for explicit recognition of dynamic facial expression is different with healthy.1.Healthy individuals showed increased activity in neural regions for the response to happy when compared with major depression.Patients showed attenuated ability to percept facial motion activation and decreased activation in emotion regulation-related brain regions.2.Contrary with recognition of happy,major depression showed increased activity in neural regions for the response to sad when compared with healthy individuals3.It was observed that male and female subjects used a rather different set of neural correlates when processing faces showing either happy or sad expressions.Our findings suggest gender-related neural responses to emotional stimuli and could contribute to the understanding of mechanisms underlying gender-related vulnerability of the prevalence and severity of neuropsychiatric disorders.This suggests that the findings in regard to neural correlates of facial emotion recognition should consider the gender of the subjects. Experiment 2:Neural substrates for explicit recognition of dynamic facial expression correlates of short-term antidepressant treatment and symptomatic response:a prospective, functional magnetic resonance imaging studyObjectives:To map brain systems activated by explicit recognition of dynamic facial expression videos in patients with depression and to identify brain functional correlates of antidepressant treatment and symptomatic response.Methods:After the baseline assessment,patients received antidepressant treatment.After 8-week period,all the patients were assessed by Hamilton Depression Rating Scale for Depression(HAMD),the patients who HAMD reducing rate≥75%underwent the second scanning using fMRI and assessed by WCST again.None of those patients who were retested in remission had received ECT.Results:1.After treatment,patients showed increased activation in right Middle Temporal Gyrus(BA37),left Superior Temporal Gyrus(BA39), left Inferior Temporal Gyrus(BA37),left Fusiform Gyrus(BA20),right Hippocampus,left Hippocampus,right Middle Frontal Gyrus(BA10), right Posterior Cingulate(BA30),right Parahippocampal Gyrus(BA36) and left Parahippocampal Gyrus(BA30);and decreased activation in right Fusiform Gyrus(BA21),left Middle Temporal Gyrus(BA21)and left Precuneus(BA19)when recognition of happy faces.2.After treatment,patients showed increased activation in left Fusiform Gyrus(BA19)and right Middle Temporal Gyrus(BA21);and decreased activation in right Fusiform Gyrus(BA19)and right Parahippocampal Gyrus(BA35)when recognition of sad faces.Conclusion:The results of this study indicate that impairments in the neural processing of facial expressions in major depressed patients were reversed following antidepressant treatment.Patients increased activation in cortical mood-regulating regions following antidepressant treatment for the response to happy.But no much difference were found in recognition of sad faces.