Altered brain morphology and functional connectivity in postmenopausal women: automatic segmentation of whole-brain and thalamic subnuclei and resting-state fMRI.

The transition to menopause is associated with various physiological changes, including alterations in brain structure and function. However, menopause-related structural and functional changes are poorly understood. The purpose of this study was not only to compare the brain volume changes between premenopausal and postmenopausal women, but also to evaluate the functional connectivity between the targeted brain regions associated with structural atrophy in postmenopausal women. Each 21 premenopausal and postmenopausal women underwent magnetic resonance imaging (MRI). T1-weighted MRI and resting-state functional MRI data were used to compare the brain volume and seed-based functional connectivity, respectively. In statistical analysis, multivariate analysis of variance, with age and whole brain volume as covariates, was used to evaluate surface areas and subcortical volumes between the two groups. Postmenopausal women showed significantly smaller cortical surface, especially in the left medial orbitofrontal cortex (mOFC), right superior temporal cortex, and right lateral orbitofrontal cortex, compared to premenopausal women (p < 0.05, Bonferroni-corrected) as well as significantly decreased functional connectivity between the left mOFC and the right thalamus was observed (p < 0.005, Monte-Carlo corrected). Although postmenopausal women did not show volume atrophy in the right thalamus, the volume of the right pulvinar anterior, which is one of the distinguished thalamic subnuclei, was significantly decreased (p < 0.05, Bonferroni-corrected). Taken together, our findings suggest that diminished brain volume and functional connectivity may be linked to menopause-related symptoms caused by the lower sex hormone levels.

Early Detection of Alzheimer's Disease in Postmenopausal Women Using Thalamic Subnuclear Volumetry.

Alzheimer's disease (AD) and aging are intrinsically interconnected with each other and are mediated by molecular, cellular, and biological systems. In particular, a specific pattern of brain volume atrophy is the most profound risk factor for cognitive impairment, including AD, that is directly linked to aging. Thus, this study aimed to investigate knowledge on the early detection of AD in postmenopausal women, focusing on the volume changes of the subcortical regions, including the thalamic subnuclei, in women with AD vs. postmenopausal women. Twenty-one women with AD and twenty-one postmenopausal women without AD underwent magnetic resonance imaging (MRI). Women with AD showed significantly reduced volumes in the hippocampus, thalamus, and amygdala compared with postmenopausal women (p < 0.05, FWE-corrected). After adjustments for age, the right hippocampal volume was found to be significantly lower in the women with AD, but the volumes of the thalamus and amygdala were relatively unaffected. The women with AD exhibited significantly reduced volume in the right laterodorsal nucleus of the thalamus compared with the postmenopausal women (p < 0.05, Bonferroni-corrected). Our findings suggest that the reduced volume of both the right laterodorsal thalamic nucleus and right hippocampus may serve as a potential biomarker for the early detection of AD in postmenopausal women.

Increased Hippocampal-Inferior Temporal Gyrus White Matter Connectivity following Donepezil Treatment in Patients with Early Alzheimer's Disease: A Diffusion Tensor Probabilistic Tractography Study.

The incidence of Alzheimer's disease (AD) has been increasing each year, and a defective hippocampus has been primarily associated with an early stage of AD. However, the effect of donepezil treatment on hippocampus-related networks is unknown. Thus, in the current study, we evaluated the hippocampal white matter (WM) connectivity in patients with early-stage AD before and after donepezil treatment using probabilistic tractography, and we further determined the WM integrity and changes in brain volume. Ten patients with early-stage AD (mean age = 72.4 ± 7.9 years; seven females and three males) and nine healthy controls (HC; mean age = 70.7 ± 3.5 years; six females and three males) underwent a magnetic resonance (MR) examination. After performing the first MR examination, the patients received donepezil treatment for 6 months. The brain volumes and diffusion tensor imaging scalars of 11 regions of interest (the superior/middle/inferior frontal gyrus, the superior/middle/inferior temporal gyrus, the amygdala, the caudate nucleus, the hippocampus, the putamen, and the thalamus) were measured using MR imaging and DTI, respectively. Seed-based structural connectivity analyses were focused on the hippocampus. The patients with early AD had a lower hippocampal volume and WM connectivity with the superior frontal gyrus and higher mean diffusivity (MD) and radial diffusivity (RD) in the amygdala than HC (p < 0.05, Bonferroni-corrected). However, brain areas with a higher (or lower) brain volume and WM connectivity were not observed in the HC compared with the patients with early AD. After six months of donepezil treatment, the patients with early AD showed increased hippocampal-inferior temporal gyrus (ITG) WM connectivity (p < 0.05, Bonferroni-corrected).

Comparative Functional Connectivity of Core Brain Regions between Implicit and Explicit Memory Tasks Underlying Negative Emotion in General Anxiety Disorder.

Objective: To investigate not only differential patterns of functional connectivity of core brain regions between implicit and explicit verbal memory tasks underlying negatively evoked emotional condition, but also correlations of functional connectivity (FC) strength with clinical symptom severity in patients with generalized anxiety disorder (GAD). Methods: Thirteen patients with GAD and 13 healthy controls underwent functional magnetic resonance imaging for memory tasks with negative emotion words. Results: Clinical symptom and its severities of GAD were potentially associated with abnormalities of task-based FC with core brain regions and distinct FC patterns between implicit vs. explicit memory processing in GAD were potentially well discriminated. Outstanding FC in implicit memory task includes positive connections of precentral gyus (PrG) to inferior frontal gyrus and inferior parietal gyrus (IPG), respectively, in encoding period; a positive connection of amygdala (Amg) to globus pallidus as well as a negative connection of Amg to cerebellum in retrieval period. Meanwhile, distinct FC in explicit memory included a positive connection of PrG to inferior temporal gyrus (ITG) in encoding period; a positive connection of the anterior cingulate gyrus to superior frontal gyrus in retrieval period. Especially, there were positive correlation between GAD-7 scores and FC of PrG-IPG (r2 = 0.324, p= 0.042) in implicit memory encoding, and FC of PrG-ITG (r2 = 0.378, p= 0.025) in explicit memory encoding. Conclusion: This study clarified differential patterns of brain activation and relevant FC between implicit and explicit verbal memory tasks underlying negative emotional feelings in GAD. These findings will be helpful for an understanding of distinct brain functional mechanisms associated with clinical symptom severities in GAD.

MRI-Based Multimodal Approach to the Assessment of Clinical Symptom Severity of Obsessive-Compulsive Disorder.

OBJECTIVE: This study assessed the associations of the abnormal brain activation and functional connectivity (FC) during memory processing and brain volume alteration in conjunction with psychiatric symptom severity in patients with obsessive-compulsive disorder (OCD). METHODS: Twenty-OCD patients and 20-healthy controls (HC) underwent T1-weighted and functional imaging underlying explicit memory task. RESULTS: In memory encoding, OCD patients showed higher activities in right/left (Rt./Lt.) inferior temporal gyrus (ITG), medial prefrontal cortex (MPFC), dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC), compared with HC. In task-based FC, caudate (Cd) was positively connected with DLPFC and ITG in OCD, while HC showed different connectivities of Cd-ACC and Rt.-Lt. ITG. In memory retrieval, only Cd was activated in OCD patients. Cd was positively connected with DLPFC and vmPFC in OCD, but negatively connected between same brain areas in HC. OCD patients showed increased gray matter (GM) volumes of cerebellum, DLPFC, orbitofrontal cortex (OFC), hippocampus, Cd and ITG, and concurrently, increased white matter volumes of DLPFC. In OCD patients, GM volumes of Cd and OFC were positively correlated with HAMA and Y-BOCS. Functional activity changes of Cd in OCD were positively correlated with Y-BOCS. CONCLUSION: Our findings support to accessing clinical symptom and its severity linked by brain structural deformation and functional abnormality in OCD patients.

A pilot study of brain morphometry following donepezil treatment in mild cognitive impairment: volume changes of cortical/subcortical regions and hippocampal subfields.

The efficacy of donepezil is well known for improving the cognitive performance in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD). Most of the recent neuroimaging studies focusing on the brain morphometry have dealt with the targeted brain structures, and thus it remains unknown how donepezil treatment influences the volume change over the whole brain areas including the cortical and subcortical regions and hippocampal subfields in particular. This study aimed to evaluate overall gray matter (GM) volume changes after donepezil treatment in MCI, which is a prodromal phase of AD, using voxel-based morphometry. Patients with MCI underwent the magnetic resonance imaging (MRI) before and after 6-month donepezil treatment. The cognitive function for MCI was evaluated using the questionnaires of the Korean version of the mini-mental state examination (K-MMSE) and Alzheimer's disease assessment scale-cognitive subscale (ADAS-Cog). Compared with healthy controls, patients with MCI showed significantly lower GM volumes in the hippocampus and its subfields, specifically in the right subiculum and left cornu ammonis (CA3). The average scores of K-MMSE in patients with MCI improved by 8% after donepezil treatment. Treated patients showed significantly higher GM volumes in the putamen, globus pailldus, and inferior frontal gyrus after donepezil treatment (p < 0.001). However, whole hippocampal volume in the patients decreased by 0.6% after 6-month treatment, and the rate of volume change in the left hippocampus was negatively correlated with the period of treatment. These findings will be useful for screening and tracking MCI, as well as understanding of the pathogenesis of MCI in connection with brain morphometric change.

White Matter Connectivity and Gray Matter Volume Changes Following Donepezil Treatment in Patients With Mild Cognitive Impairment: A Preliminary Study Using Probabilistic Tractography.

The donepezil treatment is associated with improved cognitive performance in patients with mild cognitive impairment (MCI), and its clinical effectiveness is well-known. However, the impact of the donepezil treatment on the enhanced white matter connectivity in MCI is still unclear. The purpose of this study was to evaluate the thalamo-cortical white matter (WM) connectivity and cortical thickness and gray matter (GM) volume changes in the cortical regions following donepezil treatment in patients with MCI using probabilistic tractography and voxel-based morphometry. Patients with MCI underwent magnetic resonance examinations before and after 6-month donepezil treatment. Compared with healthy controls, patients with MCI showed decreased WM connectivity of the thalamo-lateral prefrontal cortex, as well as reduced thickness in the medial/lateral orbitofrontal cortices (p < 0.05). The thalamo-lateral temporal cortex connectivity in patients with MCI was negatively correlated with Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog) (r = -0.76, p = 0.01). The average score of the Korean version of the mini-mental state examination (K-MMSE) in patients with MCI was improved by 7.9% after 6-months of donepezil treatment. However, the patterns of WM connectivity and brain volume change in untreated and treated patients were not significantly different from each other, resulting from multiple comparison corrections. These findings will be valuable in understanding the neurophysiopathological mechanism on MCI as a prodromal phase of Alzheimer's disease in connection with brain functional connectivity and morphometric change.

Metabolic alterations in acute myocardial ischemia-reperfusion injury and necrosis using in vivo hyperpolarized [1-13C] pyruvate MR spectroscopy.

This study aimed to investigate real-time early detection of metabolic alteration in a rat model with acute myocardial ischemia-reperfusion (AMI/R) injury and myocardial necrosis, as well as its correlation with intracellular pH level using in vivo hyperpolarized [1-13C] pyruvate magnetic resonance spectroscopy (MRS). Hyperpolarized 13C MRS was performed on the myocardium of 8 sham-operated control rats and 8 rats with AMI/R injury, and 8 sham-operated control rats and 8 rats with AMI-induced necrosis. Also, the correlations of levels of [1-13C] metabolites with pH were analyzed by Spearman's correlation test. The AMI/R and necrosis groups showed significantly higher ratios of [1-13C] lactate (Lac)/bicarbonate (Bicar) and [1-13C] Lac/total carbon (tC), and lower ratios of 13C Bicar/Lac + alanine (Ala), and 13C Bicar/tC than those of the sham-operated control group. Moreover, the necrosis group showed significantly higher ratios of [1-13C] Lac/Bicar and [1-13C] Lac/tC, and lower ratios of 13C Bicar/Lac + Ala and 13C Bicar/tC than those of the AMI/R group. These results were consistent with the pattern for in vivo the area under the curve (AUC) ratios. In addition, levels of [1-13C] Lac/Bicar and [1-13C] Lac/tC were negatively correlated with pH levels, whereas 13C Bicar/Lac + Ala and 13C Bicar/tC levels were positively correlated with pH levels. The levels of [1-13C] Lac and 13C Bicar will be helpful for non-invasively evaluating the early stage of AMI/R and necrosis in conjunction with reperfusion injury of the heart. These findings have potential application to real-time evaluation of cardiac malfunction accompanied by changes in intracellular pH level and enzymatic activity.

Brain Morphological Changes With Functional Deficit Associated With Sexual Arousal in Postmenopausal Women.

INTRODUCTION: We have not known how menopause synchronously influences brain morphology and function associated with visually stimulated sexual arousal in postmenopausal women. AIM: This study used a combination of functional magnetic resonance imaging and voxel-based morphometry to evaluate menopause-related brain morphological and functional changes in postmenopausal women. METHODS: Nineteen premenopausal women and 19 postmenopausal women underwent functional and structural magnetic resonance imaging. Brain function activity was measured while the subjects viewed an erotic video clip. MAIN OUTCOME MEASURES: A 2-sample t-test was used for cross-analysis of the 2 groups for comparison of gray matter volumes (corrected P < .05) and brain activation (uncorrected P < .01). RESULTS: Our study revealed a relationship between sexual function and morphological changes in postmenopausal women. Compared with premenopausal women, the postmenopausal group showed significantly lower brain activations in the major parts of the limbic system and basal ganglia, including the parahippocampal gyrus, head of caudate nucleus, insula, putamen, hippocampus, hypothalamus, amygdala, and globus pallidus, which are involved in sexual behavior and emotional responses. In morphometric analyses, postmenopausal women showed significantly decreased gray matter volumes of the insula, putamen, parahippocampal gyrus, amygdala, and anterior cingulate gyrus, most of which were associated with decreased functional activity during visual sexual arousal in postmenopausal women. In addition, the premenopausal group alone showed a positive correlation between the activity of the insula and the level of estradiol (Pearson correlation r = 0.588; P = .008). CONCLUSION: This study demonstrates an association between menopause-related brain function and morphological changes in postmenopausal women. This finding provides insight into the neural mechanisms associated with the sexual functional deficit in postmenopausal women. Baek H-S, Kim G-W, Sundaram T, et al. Brain Morphological Changes with Functional Deficit Associated with Sexual Arousal in Postmenopausal Women. Sex Med 2019;7:480-488.

Brain Activation Patterns Associated with the Effects of Fearful Distractors during Working Memory Maintenance in Patients with Schizophrenia.

OBJECTIVE: The neural correlates underlying the effects of emotional distraction during working memory (WM) tasks in patients with schizophrenia have yet to be clearly identified. Thus, the present study employed functional magnetic resonance imaging (fMRI) to investigate the effects of emotional distraction involving fear during WM maintenance in patients with schizophrenia. METHODS: This study included 17 patients with schizophrenia who were diagnosed based on Diagnostic and Statistical Manual of Mental Disorders fourth edition, text revision (DSM-IV-TR) criteria and 17 matched healthy controls. Event-related fMRI data were acquired while the participants performed a delayed-response WM task that included neutral and fearful distractors. RESULTS: Patients with schizophrenia may have tried to maintain WM function during the presentation of task-irrelevant fearful distractors that induced interruption and required attention. Compared to healthy controls, the schizophrenia patients exhibited significantly increased activity in the dorsolateral prefrontal cortex, medial prefrontal cortex, superior temporal gyrus, middle temporal gyrus, insula, hippocampus, caudate nucleus, and postcentral gyrus in a delayed-response WM task when presented with fearful relative to neutral distractors. In addition to its series of increased brain activations, prefrontal areas exhibited interconnections with more caudal brain regions, including temporal areas and the hippocampus and insula. CONCLUSION: The present study identified specific brain areas associated with the interaction between emotional regulation and cognitive functioning during fearful distractors presented while patients with schizophrenia performed a WM maintenance task. These findings further the current understanding of the neural correlates underlying the effects of emotional distraction on cognitive functioning in patients with schizophrenia.

A comparative study of white matter volume between postoperative female-to-male transsexuals and healthy female.

Cross-sex hormones in female-to-male (FtM) transsexuals play a crucial role in brain plasticity. Morphological study associated with white matter (WM) volume in postoperative FtM transsexuals receiving cross-sex hormones has not been published yet. This study was performed to discriminate the regional WM volume differences between postoperative FtM transsexuals and female controls using voxel-based morphometry (VBM) and further to assess the correlations between regional volume variations and cross-sex hormones. WM volume was assessed in 12 postoperative FtM transsexuals receiving cross-sex hormones with 16 age-matched female controls. WM volume was processed using SPM8 software with diffeomorphic anatomical registration via an exponentiated Lie algebra (DARTEL) algorithm. Serum sex hormones, including estriol, free testosterone (free-T), estradiol, follicle-stimulating hormone, and luteinizing hormone were measured. Postoperative FtM transsexuals showed significantly (p < 0.05) larger WM volumes in the inferior parietal lobule, postcentral gyrus, and middle temporal gyrus compared with female controls. However, there were no brain areas with larger WM volume in female controls compared with FtM transsexuals. WM volumes of the inferior parietal lobule and middle temporal gyrus in FtM transsexuals were positively correlated with the levels of free-T. This study revealed WM volume change and its correlation with free-T level in postoperative FtM transsexuals. These findings will improve our understanding of the morphometric changes in FtM transsexuals under cross-sex hormone therapy.

Effects of Sex Hormones and Age on Brain Volume in Post-Menopausal Women.

BACKGROUND: Investigation of the effect of sex hormones on the brain volume in women provides a unique opportunity to examine menopause-related morphometric alterations. AIM: To evaluate brain morphological alterations in post-menopausal women using voxel-based morphometry and its correlations with sex hormone levels. METHODS: 20 Pre-menopausal women and 20 post-menopausal women underwent structural MRI. OUTCOMES: T1-weighted magnetic resonance data were acquired and serum sex hormones including total estrogen, estriol, estradiol (E2), follicle-stimulating hormone, free testosterone, SHBG, and luteinizing hormone were measured. RESULTS: Post-menopausal women showed decreased gray matter (GM) in the supplementary motor area (SMA), inferior frontal gyrus, olfactory cortex, and superior temporal gyrus as contrasted with pre-menopausal women using analysis of covariance (P < .05). The GM volume (GMV) values of the SMA, inferior frontal gyrus, and superior temporal gyrus were positively correlated with the levels of E2 in the pre-menopausal and post-menopausal women, in which the volume of the SMA was negatively correlated with the duration of time after menopause in post-menopausal women. CLINICAL TRANSLATION: This finding is potentially applicable to assess the brain dysfunction with morphological changes in post-menopausal women. CONCLUSIONS: Our study is the first to evaluate a direct relationship between the level of E2 and GMV change. We directly compared pre-menopausal and menopausal women un-matched in age. This study highlights the menopause-related morphological alterations in post-menopausal women, suggesting that the reduced GMV were closely associated with the symptoms of menopause caused by the decreased levels of E2. Kim G-W, Park K, Jeong G-W. Effects of Sex Hormones and Age on Brain Volume in Post-Menopausal Women. J Sex Med 2018;15:662-670.

Whole-brain volume alteration and its correlation with anxiety severity in patients with obsessive-compulsive disorder and generalized anxiety disorder.

PURPOSE: To evaluate the differential gray matter (GM) and white matter volume alterations between healthy controls and patients with obsessive-compulsive disorder (OCD) and generalized anxiety disorder (GAD) using voxel-based morphometry (VBM). METHOD: Patients with OCD and GAD, and healthy controls underwent MR. RESULTS: Patients with GAD showed significantly decreased GM volume in the medial prefrontal cortex (mPFC) compared with patients with OCD (p < 0.001). The GM volumes of the mPFC in patients with GAD were negatively correlated with Hamilton Anxiety Rating Scales. CONCLUSION: Our findings indicate that the mPFC volume abnormality may be associated with anxiety disorder in patients with GAD rather than OCD.

Metabolic alterations in a rat model of hepatic ischaemia reperfusion injury: In vivo hyperpolarized 13 C MRS and metabolic imaging.

BACKGROUND & AIMS: Despite a number of studies addressing the pathophysiology of hepatic IRI, a gold standard test for early diagnosis and evaluation of IRI remains elusive. This study investigated the metabolic alterations in a rat model of hepatic IRI using the in vivo hyperpolarized ¹³C MRS and metabolic imaging. METHODS: Hyperpolarized 13 C MRS with IVIM-DWI was performed on the liver of 7 sham-operated control rats and 7 rats before and after hepatic IRI. RESULTS: The hepatic IRI-induced rats showed significantly higher ratios of [1-13 C] alanine/pyruvate, [1-13 C] alanine/tC, [1-13 C] lactate/pyruvate and [1-13 C] lactate/tC compared with both sham-operated controls and rats before IRI, whereas [1-13 C] pyruvate/tC ratio was decreased in IRI-induced rats. In IVIM-DWI study, apparent diffusion coefficient (ADC), f and D values in rats after hepatic IRI were significantly lower than those of rats before IRI and sham-operated controls. The levels of [1-13 C] alanine and [1-13 C] lactate were negatively correlated with ADC, f and D values, whereas the level of [1-13 C] pyruvate was positively correlated with these values. CONCLUSIONS: The levels of [1-13 C] alanine, [1-13 C] lactate and [1-13 C] pyruvate in conjunction with IVIM-DWI will be helpful to evaluate the hepatic IRI as well as these findings can be useful in understanding the biochemical mechanism associated with hepatic damage.

Associations of neurofunctional, morphometric and metabolic abnormalities with clinical symptom severity and recognition deficit in obsessive-compulsive disorder.

BACKGROUND: Obsessive-compulsive disorder (OCD) causes neural dysfunction associated with cognitive deficit and emotional dysregulation. This study assessed the associations of the neurofunctional changes, gray matter (GM) and white matter (WM) volume alterations in conjunction with in vivo metabolic changes on the working memory tasks in patients with OCD. METHODS: Eighteen patients with OCD and 18 healthy controls matched for age, sex, and educational levels underwent high-resolution T1-weighted magnetic resonance imaging (MRI), event-related functional MRI (fMRI), and proton magnetic resonance spectroscopy (1H-MRS) at 3T. RESULTS: In fMRI, patients with OCD showed lower activities in the cerebellum, inferior temporal gyrus, orbitofrontal gyrus, dorsolateral prefrontal cortex and calcarine gyrus compared to the controls. In VBM, the patients showed significantly reduced GM volumes, especially in the cerebellum, hippocampus, and superior temporal gyrus, together with significantly reduced WM volumes in the retrolenticular part of the internal capsule, dorsolateral prefrontal cortex (DLPFC) and orbitofrontal gyrus. In 1H-MRS, the ratios of N-acetylaspartate/creatine and choline/creatine were significantly lower in the DLPFC of the patients than in the controls, whereas the ratio of ß∙γ-glutamine-glutamate/creatine was significantly higher in the patients than in the controls. LIMITATIONS: This study examined small numbers of subjects in each one of the groups. CONCLUSIONS: The findings will be helpful to aid us in understanding of neurocognitive impairment in OCD, and thus, enhancing the diagnostic accuracy for OCD by additional information on the associated brain functional deficit, cerebral volume change and metabolic abnormality.

Whole brain volume changes and its correlation with clinical symptom severity in patients with schizophrenia: A DARTEL-based VBM study.

The purpose of this study was to evaluate gray matter (GM) and white matter (WM) volume alterations in whole-brain structures in patients with schizophrenia and healthy controls using voxel-based morphometry (VBM), and further to assess the correlation between GM and WM volume variations and symptom severity in schizophrenia. A total of 22 patients with schizophrenia and 22 age-matched healthy controls participated. Magnetic resonance image data were processed using SPM8 software with diffeomorphic anatomical registration via an exponentiated Lie algebra (DARTEL) algorithm. Patients with schizophrenia exhibited significantly decreased GM volumes of the insula, superior temporal gyrus (STG), gyrus rectus, and anterior cingulate cortex (ACC) compared with healthy controls. The GM volumes of the STG and gyrus rectus were negatively correlated with the positive scales on the Positive and Negative Syndrome Scale (PANSS) and those of the STG and ACC were negatively correlated with the negative scales. The durations of illness in schizophrenia were negatively correlated with the GM volumes of the insula, STG, and ACC. Patients with schizophrenia exhibited significantly decreased WM volumes of the superior frontal gyrus, inferior temporal gyrus, and STG. The WM volumes of the STG were negatively correlated with the duration of illness. Our findings suggest that GM and WM volume abnormalities in the STG are associated with the psychopathology of schizophrenia.

Comparative functional neuroanatomy between implicit and explicit memory tasks under negative emotional condition in schizophrenia.

PURPOSE: To evaluate the brain activation patterns in response to negative emotion during implicit and explicit memory in patients with schizophrenia. MATERIAL AND METHODS: Fourteen patients with schizophrenia and 14 healthy controls were included in this study. The 3.0T fMRI was obtained while the subjects performed the implicit and explicit retrievals with unpleasant words. RESULTS: The different predominant brain activation areas were observed during the implicit retrieval and explicit with unpleasant words. CONCLUSION: The differential neural mechanisms between implicit and explicit memory tasks associated with negative emotional processing in schizophrenia.

Functional neuroanatomy associated with the interaction between emotion and cognition in explicit memory tasks in patients with generalized anxiety disorder.

BACKGROUND: The functional neuroanatomy for explicit memory in conjunction with the major anxiety symptoms in patients with generalized anxiety disorder (GAD) has not yet been clearly identified. PURPOSE: To investigate the brain activation patterns on the interaction between emotional and cognitive function during the explicit memory tasks, as well as its correlation with clinical characteristics in GAD. MATERIAL AND METHODS: The participants comprised GAD patients and age-matched healthy controls. The fMR images were obtained while the participants performed an explicit memory task with neutral and anxiety-inducing words. RESULTS: Patients showed significantly decreased functional activities in the putamen, head of the caudate nucleus, hippocampus, and middle cingulate gyrus during the memory tasks with the neutral and anxiety-inducing words, whereas the precentral gyrus and ventrolateral prefrontal cortex were significantly increased only in the memory tasks with the anxiety-inducing words. Also, the blood oxygenation level-dependent (BOLD) signal changes in the hippocampus were positively correlated with the recognition accuracy for both neutral and anxiety-inducing words. CONCLUSION: This study identified the brain areas associated with the interaction between emotional regulation and cognitive function in the explicit memory tasks in patients with GAD. These findings would be helpful to understand the neural mechanism on the explicit memory-related cognitive deficits and emotional dysfunction with GAD symptoms.

Abnormalities in gray and white matter volumes associated with explicit memory dysfunction in patients with generalized anxiety disorder.

Background The neuroanatomical abnormalities associated with behavioral dysfunction on explicit memory in patients generalized anxiety disorder (GAD) have not yet been clearly identified. Purpose To investigate the regional gray matter (GM) and white matter (WM) volume alterations over the whole brain in patients with GAD, as well as the correlation between the brain structural abnormality and explicit memory dysfunction. Material and Methods Twenty patients with GAD and 20 healthy controls matched for age, sex, and education level underwent high-resolution T1-weighted magnetic resonance imaging (MRI). The participants performed the explicit memory tasks with the neutral and anxiety-inducing words. Results Patients with GAD showed significantly reduced GM volumes in the midbrain (MB), thalamus, hippocampus (Hip), insula, and superior temporal gyrus (STG); and reduced WM volumes in the MB, anterior limb of the internal capsule (ALIC), dorsolateral prefrontal cortex (DLPFC), and precentral gyrus (PrG). It is important to note that the GM volume of the Hip and the WM volume of the DLPFC were positively correlated with the recognition accuracy (%) in the explicit memory tasks with neutral and anxiety-inducing words, respectively. On the other hand, the WM volume of the PrG was negatively correlated with the reaction time in the same memory tasks. Conclusion This study demonstrated the regional volume changes on whole-brain GM and WM and the correlation between the brain structural alteration and explicit memory dysfunction in GAD patients. These findings would be helpful to understand the association between the brain structure abnormality and the functional deficit in the explicit memory in GAD.