Drinking severity mediates the relationship between hypothalamic connectivity and rule-breaking/intrusive behavior differently in young women and men: an exploratory study.

Background: The hypothalamus is a key hub of the neural circuits of motivated behavior. Alcohol misuse may lead to hypothalamic dysfunction. Here, we investigated how resting-state hypothalamic functional connectivities are altered in association with the severity of drinking and clinical comorbidities and how men and women differ in this association. Methods: We employed the data of the Human Connectome Project. A total of 870 subjects were included in data analyses. The severity of alcohol use was quantified for individual subjects with the first principal component (PC1) identified from principal component analyses of all drinking measures. Rule-breaking and intrusive scores were evaluated with the Achenbach Adult Self-Report Scale. We performed a whole-brain regression of hypothalamic connectivities on drinking PC1 in all subjects and men/women separately and evaluated the results at a corrected threshold. Results: Higher drinking PC1 was associated with greater hypothalamic connectivity with the paracentral lobule (PCL). Hypothalamic PCL connectivity was positively correlated with rule-breaking score in men (r=0.152, P=0.002) but not in women. In women but not men, hypothalamic connectivity with the left temporo-parietal junction (LTPJ) was negatively correlated with drinking PC1 (r=-0.246, P<0.001) and with intrusiveness score (r=-0.127, P=0.006). Mediation analyses showed that drinking PC1 mediated the relationship between hypothalamic PCL connectivity and rule-breaking score in men and between hypothalamic LTPJ connectivity and intrusiveness score bidirectionally in women. Conclusions: We characterized sex-specific hypothalamic connectivities in link with the severity of alcohol misuse and its comorbidities. These findings extend the literature by elucidating the potential impact of problem drinking on the motivation circuits.

Androgen deprivation increases frontopolar cortical thickness in prostate cancer patients: an effect of early neurodegeneration?

Androgen deprivation therapy (ADT) has been associated with adverse effects on the brain. ADT leads to altered testosterone levels that may affect brain morphology as well as cognition. Considering the reliability of cortical thickness (CT) as a marker of cognitive and brain changes, e.g., in Alzheimer's disease, we assessed the impacts of ADT on CT and working memory. Thirty men with non-metastatic prostate cancer receiving ADT and 32 patients not receiving ADT (controls or CON), matched in age and years of education, participated in N-back task and quality-of-life (QoL) assessments as well as brain imaging at baseline and prospectively at 6 months. Imaging data were processed with published routines to estimate CT and the results of a group by time flexible factorial analysis were evaluated at a corrected threshold. ADT and CON did not differ in N-back performance or QoL across time points. Relative to CON, patients receiving ADT showed significantly higher frontopolar cortex (FPC) CT at 6-month follow-up vs. baseline. Follow-up vs. baseline FPC CT change correlated negatively with changes in 2-back correct response rate and in testosterone levels across all participants. In mediation analysis, FPC CT change mediated the association between testosterone level change and 2-back accuracy rate change. Increases in FPC CT following 6 months of ADT may reflect early neurodegenerative changes in response to androgen deprivation. While no significant impact on working memory or QoL was observed over 6 months, further research of longer duration of treatment is warranted to unravel the full spectrum of cognitive and neural consequences of ADT in prostate cancer patients.

Age-related reduction in anxiety and neural encoding of negative emotional memory.

Introduction: Older adults experience less anxiety. We examined how memory of negative emotional images varied with age and may reflect age-related differences in anxiety. Methods: Fifty-one adults, age 22-80 years, underwent imaging with a memory task where negative and neutral images were displayed pseudo-randomly. They were queried post-scan about the images inter-mixed with an equal number of images never displayed. Sensitivity (d') and reporting bias (Z-score of false alarm rate; Z[FAR]) were quantified with signal detection theory. Results: Age was negatively correlated with both Spielberg State Trait Anxiety Inventory (STAI) state score and d' (negative - neutral) and positively with Z[FAR] (negative - neutral). However, STAI score and d' or Z[FAR] (negative - neutral) were not significantly correlated. In whole-brain regression, STAI score was correlated with higher activity of the right middle/superior temporal gyri/temporal parietal junction (MTG/STG/TPJ) for "negative correct - incorrect" - "neutral correct - incorrect" trials. Further, the MTG/STG/TPJ activity (ß) was also negatively correlated with age. Mediation analyses supported a complete mediation model of age → less anxiety → less MTG/STG/TPJ ß. Discussion: Together, the findings demonstrated age-related changes in negative emotional memory and how age-related reduction in anxiety is reflected in diminished temporoparietal cortical activities during encoding of negative emotional memory.

Gray Matter Atrophy in a 6-OHDA-induced Model of Parkinson's Disease.

INTRODUCTION: Magnetic resonance imaging (MRI) based brain morphometric changes in unilateral 6-hydroxydopamine (6-OHDA) induced Parkinson's disease (PD) model can be elucidated using voxel-based morphometry (VBM), study of alterations in gray matter volume and Machine Learning (ML) based analyses. METHODS: We investigated gray matter atrophy in 6-OHDA induced PD model as compared to sham control using statistical and ML based analysis. VBM and atlas-based volumetric analysis was carried out at regional level. Support vector machine (SVM)-based algorithms wherein features (volume) extracted from (a) each of the 150 brain regions (b) statistically significant features (only) and (c) volumes of each cluster identified after application of VBM (VBM_Vol) were used for training the decision model. The lesion of the 6-OHDA model was validated by estimating the net contralateral rotational behaviour by the injection of apomorphine drug and motor impairment was assessed by rotarod and open field test. RESULTS AND DISCUSSION: In PD, gray matter volume (GMV) atrophy was noted in bilateral cortical and subcortical brain regions, especially in the internal capsule, substantia nigra, midbrain, primary motor cortex and basal ganglia-thalamocortical circuits in comparison with sham control. Behavioural results revealed an impairment in motor performance. SVM analysis showed 100% classification accuracy, sensitivity and specificity at both 3 and 7 weeks using VBM_Vol. CONCLUSION: Unilateral 6-OHDA induced GMV changes in both hemispheres at 7th week may be associated with progression of the disease in the PD model. SVM based approaches provide an increased classification accuracy to elucidate GMV atrophy.

Deficient sleep, altered hypothalamic functional connectivity, depression and anxiety in cigarette smokers.

Background: Deficient sleep is implicated in nicotine dependence as well as depressive and anxiety disorders. The hypothalamus regulates the sleep-wake cycle and supports motivated behavior, and hypothalamic dysfunction may underpin comorbid nicotine dependence, depression and anxiety. We aimed to investigate whether and how the resting state functional connectivities (rsFCs) of the hypothalamus relate to cigarette smoking, deficient sleep, depression and anxiety. Methods: We used the data of 64 smokers and 198 age- and sex-matched adults who never smoked, curated from the Human Connectome Project. Deficient sleep and psychiatric problems were each assessed with Pittsburgh Sleep Quality Index (PSQI) and Achenbach Adult Self-Report. We processed the imaging data with published routines and evaluated the results at a corrected threshold, all with age, sex, and the severity of alcohol use as covariates. Results: Smokers vs. never smokers showed poorer sleep quality and greater severity of depression and anxiety. In smokers only, the total PSQI score, indicating more sleep deficits, was positively associated with hypothalamic rsFCs with the right inferior frontal/insula/superior temporal and postcentral (rPoCG) gyri. Stronger hypothalamus-rPoCG rsFCs were also associated with greater severity of depression and anxiety in smokers but not never smokers. Additionally, in smokers, the PSQI score completely mediated the relationships of hypothalamus-rPoCG rsFCs with depression and anxiety severity. Conclusions: These findings associate hypothalamic circuit dysfunction to sleep deficiency and severity of depression and anxiety symptoms in adults who smoke. Future studies may investigate the roles of the hypothalamic circuit in motivated behaviors to better characterize the inter-related neural markers of smoking, deficient sleep, depression and anxiety.

Sex differences in the effects of individual anxiety state on regional responses to negative emotional scenes.

BACKGROUND: Men and women are known to show differences in the incidence and clinical manifestations of mood and anxiety disorders. Many imaging studies have investigated the neural correlates of sex differences in emotion processing. However, it remains unclear how anxiety might impact emotion processing differently in men and women. METHOD: We recruited 119 healthy adults and assessed their levels of anxiety using State-Trait Anxiety Inventory (STAI) State score. With functional magnetic resonance imaging (fMRI), we examined regional responses to negative vs. neutral (Neg-Neu) picture matching in the Hariri task. Behavioral data were analyzed using regression and repeated-measures analysis of covariance with age as a covariate, and fMRI data were analyzed using a full-factorial model with sex as a factor and age as a covariate. RESULTS: Men and women did not differ in STAI score, or accuracy rate or reaction time (RT) (Neg-Neu). However, STAI scores correlated positively with RT (Neg-Neu) in women but not in men. Additionally, in women, STAI score correlated positively with lingual gyrus (LG) and negatively with medial prefrontal cortex (mPFC) and superior frontal gyrus (SFG) activity during Neg vs. Neu trials. The parameter estimates (ßs) of mPFC also correlated with RT (Neg-Neu) in women but not in men. Generalized psychophysiological interaction (gPPI) analysis in women revealed mPFC connectivity with the right inferior frontal gyrus, right SFG, and left parahippocampal gyrus during Neg vs. Neu trials in positive correlation with both STAI score and RT (Neg-Neu). In a mediation analysis, mPFC gPPI but not mPFC activity fully mediated the association between STAI scores and RT (Neg-Neu). CONCLUSION: With anxiety affecting the behavioral and neural responses to negative emotions in women but not in men and considering the known roles of the mPFC in emotion regulation, we discussed heightened sensitivity and regulatory demands during negative emotion processing as neurobehavioral markers of anxiety in women.

Men and women often experience and express their emotional problems in different ways. In this study, we investigated how anxiety affects negative emotion processing in men and women. By understanding these differences, we hope to elucidate how men and women differ in the perception and processing of negative emotions in association with individual differences in anxiety. To this end, we recruited 60 men and 59 women from the community. We evaluated participants' anxiety state using a validated instrument and their brain responses to negative emotional and neutral pictures in picture matching task using functional brain imaging. The results showed that individual levels of anxiety were positively correlated with the speed of matching negative vs. neutral pictures, suggesting interference of negative emotions with cognitive motor processing, in women, but not in men. Thus, women with more severe anxiety may be more sensitive to distraction by negative emotional stimuli. In brain imaging data, the activities of the medial prefrontal cortex, a region that supports emotion regulation, during negative vs. neutral emotion processing were negatively correlated with anxiety in women, and this effect was not seen in men. Further, the medial prefrontal cortex showed connectivities with other brain regions and these functional connectivities mediated the effects of anxiety on matching speed in women. These findings suggest that heightened sensitivity to negative emotions in anxious women are possibly due to emotion dysregulation within the medial prefrontal cortex. These findings may help us better understand why women are more vulnerable to emotional problems and develop more personalized treatments for anxiety and mood disorders.

Effect of neuronavigated repetitive Transcranial Magnetic Stimulation on pain, cognition and cortical excitability in fibromyalgia syndrome.

BACKGROUND: Fibromyalgia syndrome is a widespread chronic pain condition identified by body-wide pain, fatigue, cognitive fogginess, and sleep issues. In the past decade, repetitive transcranial magnetic stimulation has emerged as a potential management tool.. In the present study, we enquired whether repetitive transcranial magnetic stimulation could modify pain, corticomotor excitability, cognition, and sleep. METHODS: Study is a randomized, sham-controlled, double-blind, clinical trial; wherein after randomizing thirty-four fibromyalgia patients into active or sham therapy (n = 17 each), each participant received repetitive transcranial magnetic stimulation therapy. In active therapy was given at 1 Hz for 20 sessions were delivered on dorsolateral prefrontal cortex (1200 pulses, 150 pulses per train for 8 trains); while in sham therapy coil was placed at right angle to the scalp with same frequency. Functional magnetic resonance imaging was used to identify the therapeutic site. Pain intensity, corticomotor excitability, cognition, and sleep were examined before and after therapy. RESULTS: Baseline demographic and clinical parameters for both active and sham groups were comparable. In comparison to sham, active repetitive transcranial magnetic stimulation showed significant difference in pain intensity (P < 0.001, effect size = 0.29, large effect) after intervention. Other parameters of pain perception, cognition, and sleep quality also showed a significant improvement after the therapy in active therapy group only, as compared to sham. CONCLUSIONS: Findings suggest that repetitive transcranial magnetic stimulation intervention is effective in managing pain alongside cognition and sleep disturbances in patients of fibromyalgia. It may prove to be an important tool in relieving fibromyalgia-associated morbidity.

Sex differences in the effects of trait anxiety and age on resting-state functional connectivities of the amygdala.

Background: Numerous studies characterized how resting-state functional connectivities (rsFCs) of the amygdala were disrupted in emotional disorders and varied with emotional traits, including anxiety. With trait anxiety known to diminish with age, a critical issue concerns disambiguating the effects of age and anxiety on amygdala rsFCs in studying the neural bases of individual differences in anxiety. Methods: Two-hundred adults (83 women) 19-85 years of age underwent fMRI and assessment for trait anxiety. Amygdala rsFC correlates were identified using multiple regression with age and anxiety in the same model for all and separately in men and women. The rsFC correlates were examined for age-anxiety interaction. Results: Anxiety was negatively correlated with amygdala-temporooccipital gyri rsFC in all and in men alone. In women, amgydala rsFC with the thalamus/pallidum, angular/supramarginal gyri, inferior temporal gyrus, and posterior insula correlated positively and rsFC with calcarine cortex and caudate correlated negatively with anxiety. We also observed sex differences in age correlation of amgydala-posterior cingulate cortex/precuneus and -insula/temporoparietal rsFCs, with stronger associations in women. In women alone, anxiety and age interacted to determine amygdala rsFC with the thalamus/pallidum, calcarine cortex, and caudate, with older age associated with stronger correlation between anxiety and the rsFCs. Limitations: The findings need to be validated in an independent sample and further explored using task-based data. Conclusion: Highlighting anxiety- and age- specific as well as interacting correlates of amygdala rsFCs and sex differences in the correlates, the findings may shed light on the neural markers of anxiety.

Resting-State Functional Connectivity of the Dorsal and Ventral Striatum, Impulsivity, and Severity of Use in Recently Abstinent Cocaine-Dependent Individuals.

BACKGROUND: Previous studies have focused on both ventral striatum (VS) and dorsal striatum (DS) in characterizing dopaminergic deficits in addiction. Animal studies suggest VS and DS dysfunction each in association with impulsive and compulsive cocaine use during early and later stages of addiction. However, few human studies have aimed to distinguish the roles of VS and DS dysfunction in cocaine misuse. METHODS: We examined VS and DS resting-state functional connectivity (rsFC) of 122 recently abstinent cocaine-dependent individuals (CDs) and 122 healthy controls (HCs) in 2 separate cohorts. We followed published routines in imaging data analyses and evaluated the results at a corrected threshold with age, sex, years of drinking, and smoking accounted for. RESULTS: CDs relative to HCs showed higher VS rsFC with the left inferior frontal cortex (IFC), lower VS rsFC with the hippocampus, and higher DS rsFC with the left orbitofrontal cortex. Region-of-interest analyses confirmed the findings in the 2 cohorts examined separately. In CDs, VS-left IFC and VS-hippocampus connectivity was positively and negatively correlated with average monthly cocaine use in the prior year, respectively. In the second cohort where participants were assessed with the Barratt Impulsivity Scale (BIS-11), VS-left IFC and VS-hippocampus connectivity was also positively and negatively correlated with BIS-11 scores in CDs. In contrast, DS-orbitofrontal cortex connectivity did not relate significantly to cocaine use metrics or BIS-11 scores. CONCLUSION: These findings associate VS rsFC with impulsivity and the severity of recent cocaine use. How DS connectivity partakes in cocaine misuse remains to be investigated.

Sleep dysfunction mediates the relationship between hypothalamic-insula connectivity and anxiety-depression symptom severity bidirectionally in young adults.

BACKGROUND: The hypothalamus plays a crucial role in regulating sleep-wake cycle and motivated behavior. Sleep disturbance is associated with impairment in cognitive and affective functions. However, how hypothalamic dysfunction may contribute to inter-related sleep, cognitive, and emotional deficits remain unclear. METHODS: We curated the Human Connectome Project dataset and investigated how hypothalamic resting state functional connectivities (rsFC) were associated with sleep dysfunction, as evaluated by the Pittsburgh Sleep Quality Index (PSQI), cognitive performance, and subjective mood states in 687 young adults (342 women). Imaging data were processed with published routines and evaluated with a corrected threshold. We examined the inter-relationship amongst hypothalamic rsFC, PSQI score, and clinical measures with mediation analyses. RESULTS: In whole-brain regressions with age and drinking severity as covariates, men showed higher hypothalamic rsFC with the right insula in correlation with PSQI score. No clusters were identified in women at the same threshold. Both hypothalamic-insula rsFC and PSQI score were significantly correlated with anxiety and depression scores in men. Further, mediation analyses showed that PSQI score mediated the relationship between hypothalamic-insula rsFC and anxiety/depression symptom severity bidirectionally in men. CONCLUSIONS: Sleep dysfunction is associated with negative emotions and hypothalamic rsFC with the right insula, a core structure of the interoceptive circuits. Notably, anxiety-depression symptom severity and altered hypothalamic-insula rsFC are related bidirectionally by poor sleep quality. These findings are specific to men, suggesting potential sex differences in the neural circuits regulating sleep and emotional states that need to be further investigated.

Age-related reduction in trait anxiety: Behavioral and neural evidence of automaticity in negative facial emotion processing.

Trait anxiety diminishes with age, which may result from age-related decline in registering salient emotional stimuli and/or enhancement in emotion regulation. We tested the hypotheses in 88 adults 21 to 85 years of age and studied with fMRI of the Hariri task. Age-related decline in stimulus registration would manifest in delayed reaction time (RT) and diminished saliency circuit activity in response to emotional vs. neutral stimuli. Enhanced control of negative emotions would manifest in diminished limbic/emotional circuit and higher prefrontal cortical (PFC) responses to negative emotion. The results showed that anxiety was negatively correlated with age. Age was associated with faster RT and diminished activation of the medial PFC, in the area of the dorsal and rostral anterior cingulate cortex (dACC/rACC) - a hub of the saliency circuit - during matching of negative but not positive vs. neutral emotional faces. A slope test confirmed the differences in the regressions. Further, age was not associated with activation of the PFC in whole-brain regression or in region-of-interest analysis of the dorsolateral PFC, an area identified from meta-analyses of the emotion regulation literature. Together, the findings fail to support either hypothesis; rather, the findings suggest age-related automaticity in processing negative emotions as a potential mechanism of diminished anxiety. Automaticity results in faster RT and diminished anterior cingulate activity in response to negative but not positive emotional stimuli. In support, analyses of psychophysiological interaction demonstrated higher dACC/rACC connectivity with the default mode network, which has been implicated in automaticity in information processing. As age increased, individuals demonstrated faster RT with higher connectivity during matching of negative vs. neutral images. Automaticity in negative emotion processing needs to be investigated as a mechanism of age-related reduction in anxiety.

The effects of age on the severity of problem drinking: Mediating effects of positive alcohol expectancy and neural correlates.

Aging is associated with reduction in the severity of alcohol misuse. However, the psychological and neural mechanisms underlying the age-related changes remain unclear. Here, we tested the hypothesis that age-related diminution of positive alcohol expectancy (AE) mediated the effects of age on problem drinking and investigated the neural correlates of the mediating effects. Ninety-six drinkers 21-85 years of age, including social drinkers and those with mild/moderate alcohol use disorder (AUD), were assessed for global positive (GP) AE and problem drinking, each with the Alcohol Expectancy Questionnaire and Alcohol Use Disorders Identification Test (AUDIT), and with brain imaging during alcohol cue exposure. We processed imaging data with published routines; identified the correlates shared between whole-brain regression against age, GP and AUDIT scores; and performed mediation and path analyses to explore the interrelationships between the clinical and neural variables. The results showed that age was negatively correlated with both GP and AUDIT scores, with GP score completely mediating the correlation between age and AUDIT score. Lower age and higher GP correlated with shared cue responses in bilateral parahippocampal gyrus and left middle occipital cortex (PHG/OC). Further, higher GP and AUDIT scores were associated with shared cue responses in bilateral rostral anterior cingulate cortex and caudate head (ACC/caudate). Path analyses demonstrated models with significant statistical fit and PHG/OC and ACC/caudate each interrelating age to GP and GP to AUDIT scores. These findings confirmed change in positive AE as a psychological mechanism mitigating alcohol misuse as individuals age and highlighted the neural processes of cue-reactivity interrelating age and alcohol use severity.

Sex differences in the effects of individual anxiety state on regional responses to negative emotional scenes.

Background: Men and women are known to show differences in the incidence and clinical manifestations of mood and anxiety disorders. Many imaging studies have investigated the neural correlates of sex differences in emotion processing. However, it remains unclear how anxiety might impact emotion processing differently in men and women. Method: We recruited 119 healthy adults and assessed their levels of anxiety using State-Trait Anxiety Inventory (STAI) State score. With functional magnetic resonance imaging (fMRI), we examined regional responses to negative vs. neutral (Neg-Neu) picture matching in the Hariri task. Behavioral data were analyzed using regression and repeated-measures analysis of covariance with age as a covariate, and fMRI data were analyzed using a full-factorial model with sex as a factor and age as a covariate. Results: Men and women did not differ in STAI score, or accuracy rate or reaction time (RT) (Neg-Neu). However, STAI scores correlated positively with RT (Neg-Neu) in women but not in men. Additionally, in women, STAI score correlated positively with lingual gyrus (LG) and negatively with medial prefrontal cortex (mPFC) and superior frontal gyrus (SFG) activity during Neg vs. Neu trials. The parameter estimates (ß's) of mPFC also correlated with RT (Neg-Neu) in women but not in men. Generalized psychophysiological interaction (gPPI) analysis in women revealed mPFC connectivity with the right inferior frontal gyrus, right SFG, and left parahippocampal gyrus during Neg vs. Neu trials in positive correlation with both STAI score and RT (Neg-Neu). In a mediation analysis, mPFC gPPI but not mPFC activity fully mediated the association between STAI scores and RT (Neg-Neu). Conclusion: With anxiety affecting the behavioral and neural responses to negative emotions in women but not in men and considering the known roles of the mPFC in emotion regulation, we discussed heightened sensitivity and regulatory demands during negative emotion processing as neurobehavioral markers of anxiety in women.

Shared and distinct neural activity during anticipation and outcome of win and loss: A meta-analysis of the monetary incentive delay task.

Reward and punishment motivate decision making and behavioral changes. Numerous studies have examined regional activities during anticipation and outcome of win and loss in the monetary incentive delay task (MIDT). However, the great majority of studies reported findings of anticipation or outcome and of win or loss alone. It remains unclear how the neural correlates share and differentiate amongst these processes. We conducted an Activation Likelihood Estimation meta-analysis of 81 studies of the MIDT (5,864 subjects), including 24 published since the most recent meta-analysis, to identify and, with conjunction and subtraction, contrast regional responses to win anticipation, loss anticipation, win outcome, and loss outcome. Win and loss anticipation engaged a shared network of bilateral anterior insula (AI), striatum, thalamus, supplementary motor area (SMA), and precentral gyrus. Win and loss outcomes did not share regional activities. Win and loss outcome each engaged higher activity in medial orbitofrontal cortex (mOFC) and dorsal anterior cingulate cortex. Bilateral striatum and right occipital cortex responded to both anticipation and outcome of win, and right AI to both phases of loss. Win anticipation vs. outcome engaged higher activity in bilateral AI, striatum, SMA and precentral gyrus and right thalamus, and lower activity in bilateral mOFC and posterior cingulate cortex as well as right inferior frontal and angular gyri. Loss anticipation relative to outcome involved higher activity in bilateral striatum and left AI. These findings collectively suggest shared and distinct regional responses during monetary wins and losses. Delineating the neural correlates of these component processes may facilitate empirical research of motivated behaviors and dysfunctional approach and avoidance in psychopathology.

Effects of androgen deprivation on white matter integrity and processing speed in prostate cancer patients.

Studies have associated chemotherapy-elicited changes in cognitive function with impaired white matter integrity in cancer patients. Androgen deprivation therapy (ADT) may lead to cognitive deficits in prostate cancer patients; however, whether ADT influences white matter integrity has never been investigated. In a prospective study, 15 men with non-metastatic prostate cancer receiving ADT and 15 not receiving ADT (controls or CON), comparable in age and years of education, participated in N-back task, flankers' task, and quality-of-life (QoL) assessments. All participants underwent diffusion tensor imaging of the brain at baseline and at 6 months. Imaging data were processed with published routines. The results of a paired t-test of 6-month follow-up vs. baseline were evaluated at a corrected threshold for the whole brain each in ADT and CON. ADT patients showed significantly worse 1-back accuracy during follow-up, but the two groups did not differ in 2-back accuracy, 1- or 2-back reaction time (RT), flankers' task RT or QoL across time points. In ADT, significantly reduced fractional anisotropy (FA) was noted in the corpus callosum, forceps minor/anterior thalamic radiation, superior and posterior corona radiata. The differences in FA correlated significantly with changes in 2-back and flankers' task RT. No significant FA changes were noted during follow-up in CON. Six-month ADT affects white matter integrity, and the deficits were associated with slower processing speed. These findings add to the literature supporting the deleterious effects of androgen deprivation on the brain and cognition in prostate cancer patients.

Hypothalamic Functional Connectivity and Apathy in People with Alzheimer's Disease and Cognitively Normal Healthy Controls.

BACKGROUND: Earlier studies have described the neural markers of apathy in Alzheimer's disease (AD) and mild cognitive impairment (MCI), but few focused on the motivation circuits. Here, we targeted hypothalamus, a hub of the motivation circuit. OBJECTIVE: To examine hypothalamic resting state functional connectivity (rsFC) in relation to apathy. METHODS: We performed whole-brain regression of hypothalamic rsFC against Apathy Evaluation Scale (AES) total score and behavioral, cognitive, and emotional subscores in 29 patients with AD/MCI and 28 healthy controls (HC), controlling for age, sex, education, cognitive status, and depression. We evaluated the results at a corrected threshold and employed path analyses to assess possible interaction between hypothalamic rsFCs, apathy and depression/memory. Finally, we re-examined the findings in a subsample of amyloid-ß-verified AD. RESULTS: AES total score correlated negatively with hypothalamic precuneus (PCu)/posterior cingulate cortex (PCC) and positively with left middle temporal gyrus (MTG) and supramarginal gyrus rsFCs. Behavioral subscore correlated negatively with hypothalamic PCu/PCC and positively with middle frontal gyrus rsFC. Cognitive subscore correlated positively with hypothalamic MTG rsFC. Emotional subscore correlated negatively with hypothalamic calcarine cortex rsFC. In path analyses, hypothalamic-PCu/PCC rsFC negatively modulated apathy and, in turn, depression. The model where hypothalamic MTG rsFC and memory independently modulated apathy also showed a good fit. The findings of diminished hypothalamic-PCu/PCC rsFC in relation to apathy and, in turn, depression were confirmed in amyloid-verified AD. CONCLUSION: The findings together support a role of altered hypothalamic connectivity in relation to apathy and depression, and modulation of apathy by memory dysfunction.

Overnight Abstinence Is Associated With Smaller Secondary Somatosensory Cortical Volumes and Higher Somatosensory-Motor Cortical Functional Connectivity in Cigarette Smokers.

INTRODUCTION: Abstinence symptoms present challenges to successful cessation of cigarette smoking. Chronic exposure to nicotine and long-term nicotine abstinence are associated with alterations in cortical and subcortical gray matter volumes (GMVs). AIMS AND METHODS: We aimed at examining changes in regional GMVs following overnight abstinence and how these regional functions relate to abstinence symptoms. Here, in a sample of 31 regular smokers scanned both in a satiety state and after overnight abstinence, we employed voxel-wise morphometry and resting-state functional connectivity (rsFC) to investigate these issues. We processed imaging data with published routines and evaluated the results with a corrected threshold. RESULTS: Smokers showed smaller GMVs of the left ventral hippocampus and right secondary somatosensory cortex (SII) after overnight abstinence as compared to satiety. The GMV alterations in right SII were positively correlated with changes in withdrawal symptom severity between states. Furthermore, right SII rsFC with the precentral gyrus was stronger in abstinence as compared to satiety. The inter-regional rsFC was positively correlated with motor impulsivity and withdrawal symptom severity during abstinence and negatively with craving to smoke during satiety. CONCLUSIONS: These findings highlight for the first time the effects of overnight abstinence on cerebral volumetrics and changes in functional connectivity of a higher-order sensory cortex. These changes may dispose smokers to impulsive behaviors and aggravate the urge to smoke at the earliest stage of withdrawal from nicotine. IMPLICATIONS: Overnight abstinence leads to changes in gray matter volumes and functional connectivity of the second somatosensory cortex in cigarette smokers. Higher somatosensory and motor cortical connectivity in abstinence is significantly correlated with trait motor impulsivity and withdrawal symptom severity. The findings add to the literature of neural markers of nicotine addiction.

Loss and Frontal Striatal Reactivities Characterize Alcohol Use Severity and Rule-Breaking Behavior in Young Adult Drinkers.

BACKGROUND: Alcohol misuse is associated with externalizing behaviors, including rule breaking. Studies have implicated altered reward processing in externalizing behaviors and alcohol misuse. Here, we investigated whether reward or punishment reactivity more significantly influenced alcohol use severity and rule-breaking behavior in young adult drinkers. METHODS: We curated data from the Human Connectome Project and identified 181 binge (132 men) and 288 nonbinge (97 men) drinkers performing a gambling task during brain imaging. Alcohol use severity was quantified by the first principal component of principal-component analysis of all drinking measures. We analyzed the imaging data using published routines and evaluated the results at a corrected threshold. We examined the interrelationship between imaging and clinical metrics with mediation and path analyses. RESULTS: Compared with nonbingers, bingers showed more severe rule-breaking behavior and responded significantly faster during post-loss than during post-win trials. Compared with nonbingers, bingers demonstrated greater inferior/middle frontal gyrus and cerebellum activations in loss-predominating blocks but no differences in regional responses to win-predominating blocks, relative to an interblock baseline. The right caudate body showed loss reactivity that was positively correlated with the rule-breaking score. No regional responses to wins were significantly correlated with the rule-breaking score. Mediation and path analyses demonstrated significant models with inferior/middle frontal gyrus and caudate reactivity to loss interrelating rule breaking and alcohol use severity. CONCLUSIONS: Punishment rather than reward reactivity was associated with alcohol use severity and rule breaking in young adults. The findings highlight the roles of negative emotions in psychological models of externalizing behaviors and alcohol misuse.

Hypothalamic connectivities predict individual differences in ADT-elicited changes in working memory and quality of life in prostate cancer patients.

Androgen deprivation therapy (ADT) has been associated with adverse effects on cognition. However, we currently lack understanding of the neurobiology and prognostic markers of these effects. Given that ADT acts via the hypothalamus-pituitary-gonadal axis, we assessed whether baseline hypothalamic resting state functional connectivity (rsFC) could predict changes in working memory and quality of life in prostate cancer patients following androgen deprivation. In a prospective observational study, 28 men with non-metastatic prostate cancer receiving ADT and 38 patients not receiving ADT (controls), matched in age, years of education and Montreal Cognitive Assessment score, participated in brain imaging at baseline, and N-back task and quality-of-life (QoL) assessments at baseline and at 6 months follow-up. Imaging data were processed with published routines and evaluated at a corrected threshold. ADT and control groups did not differ in N-back performance or QoL across time points. In ADT, the changes in 0-back correct response rate (follow-up-baseline) were correlated with baseline hypothalamus-precentral gyrus rsFC; the changes in 1-back correct response rate and reaction time were each correlated with hypothalamus-middle frontal gyrus and superior parietal lobule rsFC. The changes in physical well-being subscore of QoL were correlated with baseline hypothalamus-anterior cingulate and cuneus rsFC. The hypothalamus rsFCs predicted N-back and QoL change with an area under the receiver operating characteristic curve of 0.93 and 0.73, respectively. Baseline hypothalamus-frontoparietal and salience network rsFC's predict inter-subject variations in the changes in working-memory and QoL following 6 months of ADT. Whether and how hypothalamic rsFCs may predict the cognitive and QoL effects with longer-term ADT remain to be investigated.

Emotion Processing Dysfunction in Alzheimer's Disease: An Overview of Behavioral Findings, Systems Neural Correlates, and Underlying Neural Biology.

We described behavioral studies to highlight emotional processing deficits in Alzheimer's disease (AD). The findings suggest prominent deficit in recognizing negative emotions, pronounced effect of positive emotion on enhancing memory, and a critical role of cognitive deficits in manifesting emotional processing dysfunction in AD. We reviewed imaging studies to highlight morphometric and functional markers of hippocampal circuit dysfunction in emotional processing deficits. Despite amygdala reactivity to emotional stimuli, hippocampal dysfunction conduces to deficits in emotional memory. Finally, the reviewed studies implicating major neurotransmitter systems in anxiety and depression in AD supported altered cholinergic and noradrenergic signaling in AD emotional disorders. Overall, the studies showed altered emotions early in the course of illness and suggest the need of multimodal imaging for further investigations. Particularly, longitudinal studies with multiple behavioral paradigms translatable between preclinical and clinical models would provide data to elucidate the time course and underlying neurobiology of emotion processing dysfunction in AD.