The cerebellum on the rise in human emotion

Cerebellar Neurostimulation for Boosting Social and Affective Functions: Implications for the Rehabilitation of Hereditary Ataxia Patients

Beyond motor deficits, spinocerebellar ataxia (SCA) patients also suffer cognitive decline and show socio-affective difficulties, negatively impacting on their social functioning. The possibility to modulate cerebello-cerebral networks involved in social cognition through cerebellar neurostimulation has opened up potential therapeutic applications for ameliorating social and affective difficulties. The present review offers an overview of the research on cerebellar neurostimulation for the modulation of socio-affective functions in both healthy individuals and different clinical populations, published in the time period 2000-2022. A total of 25 records reporting either transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) studies were found. The investigated clinical populations comprised different pathological conditions, including but not limited to SCA syndromes. The reviewed evidence supports that cerebellar neurostimulation is effective in improving social abilities in healthy individuals and reducing social and affective symptoms in different neurological and psychiatric populations associated with cerebellar damage or with impairments in functions that involve the cerebellum. These findings encourage to further explore the rehabilitative effects of cerebellar neurostimulation on socio-affective deficits experienced by patients with cerebellar abnormalities, as SCA patients. Nevertheless, conclusions remain tentative at this stage due to the heterogeneity characterizing stimulation protocols, study methodologies and patients' samples.

Effects of stress-related neuromodulators on amygdala and hippocampus resting state functional connectivity

BACKGROUND

The human stress response is characterized by increases in neuromodulators, including norepinephrine (NE) and cortisol. Both neuromodulators can enter the brain and affect neurofunctional responses. Two brain areas associated with stress are the amygdala and the hippocampus. The precise influence of NE and cortisol on the amygdala and hippocampal resting state functional connectivity (RSFC) is poorly understood.

AIMS

To investigate the influence of NE and cortisol on the amygdala and hippocampal RSFC.

METHODS

We recruited 165 participants who received 10 mg yohimbine and/or 10 mg hydrocortisone in a randomized, placebo-controlled design. With seed-based analyses, we compared RSFC of the hippocampus and amygdala separately between the three groups that received medication versus placebo.

RESULTS

We found no differences between yohimbine and placebo condition or between hydrocortisone and placebo condition regarding amygdala or hippocampal FC. Compared with placebo, the yohimbine/hydrocortisone condition showed increased amygdala and hippocampal RSFC with the cerebellum. Also, they had increased hippocampal RSFC with the amygdala and cerebral white matter.

DISCUSSION

The group with elevated NE and cortisol showed significantly increased RSFC between the amygdala, hippocampus, and cerebellum compared to placebo. These three brain areas are involved in associative learning and emotional memory, suggesting a critical role for this network in the human stress response. Our results show that NE and cortisol together may influence the strength of this association. Compared to placebo, we found no differences in the groups receiving only one medication, suggesting that increasing one neuromodulator alone may not induce differences in neurofunctional responses. The study procedure has been registered at clinicaltrials.gov (ID: NCT04359147).

Cerebellum function: The chronometry of social perception

The posterior cerebellum is emerging as a key structure for social cognition. A new study causally demonstrates its early involvement during emotion perception and functional connectivity with the posterior superior temporal sulcus, a cortical hub of the social brain.

Doubling down on dual systems: A cerebellum-amygdala route towards action- and outcome-based social and affective behavior

The amygdala and cerebellum are both evolutionary preserved brain structures containing cortical as well as subcortical properties. For decades, the amygdala has been considered the fear-center of the brain, but recent advances have shown that the amygdala acts as a critical hub between cortical and subcortical systems and shapes social and affective behaviors beyond fear. Likewise, the cerebellum is a dedicated control unit that fine-tunes motor behavior to fit contextual requirements. There is however increasing evidence that the cerebellum strongly influences subcortical as well as cortical processes beyond the motor domain. These insights broadened the view on the cerebellum's functions to also include social and affective behavior. Here we explore how the amygdala and cerebellum might interact in shaping social and affective behaviors based on their roles in threat reactivity and reinforcement learning. A novel mechanistic neural framework of cerebellum-amygdala interactions will be presented which provides testable hypotheses for future social and affective neuroscientific research in humans.

Common and distinct neural correlates of emotional processing in individuals at familial risk for major depressive disorder and bipolar disorder: A comparative meta-analysis

Individuals at familial risk for mood disorders exhibit deficits in emotional processing and associated brain dysfunction prior to illness onset. However, such brain-behavior abnormalities related to familial predisposition remain poorly understood. To investigate robust abnormal functional activation patterns during emotional processing in unaffected at-risk relatives of patients with major depressive disorder (UAR-MDD) and bipolar disorder (UAR-BD), we performed a meta-analysis of task-based functional magnetic resonance imaging studies using Seed-based d Mapping (SDM) toolbox. Common and distinct patterns of abnormal functional activation between UAR-MDD and UAR-BD were detected via conjunction and differential analyses. A total of 17 studies comparing 481 UAR and 670 healthy controls (HC) were included. Compared with HC, UAR-MDD exhibited hyperactivation in the parahippocampal gyrus, amygdala and cerebellum, while UAR-BD exhibited parahippocampal hyperactivation and hypoactivation in the striatum and middle occipital gyrus (MOG). Conjunction analysis revealed shared hyperactivated PHG in both groups. Differential analysis indicated that the activation patterns of amygdala and MOG significantly differed between UAR-MDD and UAR-BD. These findings provide novel insights into common and distinct neural phenotypes for familial risk and associated risk mechanisms in MDD and BD, which may have implications in guiding precise prevention strategies tailored to the family context.

Smaller total and subregional cerebellar volumes in posttraumatic stress disorder: a mega-analysis by the ENIGMA-PGC PTSD workgroup

Although the cerebellum contributes to higher-order cognitive and emotional functions relevant to posttraumatic stress disorder (PTSD), prior research on cerebellar volume in PTSD is scant, particularly when considering subregions that differentially map on to motor, cognitive, and affective functions. In a sample of 4215 adults (PTSD n = 1642; Control n = 2573) across 40 sites from the ENIGMA-PGC PTSD working group, we employed a new state-of-the-art deep-learning based approach for automatic cerebellar parcellation to obtain volumetric estimates for the total cerebellum and 28 subregions. Linear mixed effects models controlling for age, gender, intracranial volume, and site were used to compare cerebellum volumes in PTSD compared to healthy controls (88% trauma-exposed). PTSD was associated with significant grey and white matter reductions of the cerebellum. Compared to controls, people with PTSD demonstrated smaller total cerebellum volume, as well as reduced volume in subregions primarily within the posterior lobe (lobule VIIB, crus II), vermis (VI, VIII), flocculonodular lobe (lobule X), and corpus medullare (all p-FDR < 0.05). Effects of PTSD on volume were consistent, and generally more robust, when examining symptom severity rather than diagnostic status. These findings implicate regionally specific cerebellar volumetric differences in the pathophysiology of PTSD. The cerebellum appears to play an important role in higher-order cognitive and emotional processes, far beyond its historical association with vestibulomotor function. Further examination of the cerebellum in trauma-related psychopathology will help to clarify how cerebellar structure and function may disrupt cognitive and affective processes at the center of translational models for PTSD.

Characterizing Typhoon-related Posttraumatic Stress Disorder Based on Multimodal Fusion of Structural, Diffusion, and Functional Magnetic Resonance Imaging

Diagnosing posttraumatic stress disorder (PTSD) using only single-modality images is controversial. We aimed to use multimodal magnetic resonance imaging (MRI) combining structural, diffusion, and functional MRI to possibly provide a more comprehensive viewpoint on the decisive characteristics of PTSD patients. Typhoon-exposed individuals with (n = 26) and without PTSD (n = 32) and healthy volunteers (n = 30) were enrolled. Five MRI features from three modalities, including two resting-state functional MRI (rs-fMRI) features (amplitude of low-frequency fluctuation, ALFF; and regional homogeneity, ReHo), one structural MRI feature (gray matter density, GM), and two diffusion tensor imaging (DTI) features (fractional anisotropy, FA; and mean diffusivity, MD) were investigated simultaneously with a multimodal canonical correlation analysis + joint independent component analysis model to identify abnormalities in the PTSD brain. We identified statistical differences between PTSD patients and healthy controls in terms of 1 rs-fMRI (ALFF, ReHo) alterations in the superior frontal gyrus, precuneus, inferior parietal lobule (IPL), anterior cingulate cortex (ACC), and posterior cingulate cortex (PCC), 2 DTI (FA, MD) changes in the pons, genu, and splenium of the corpus callosum, and 3 Structural MRI abnormalities in the precuneus, IPL, ACC, and PCC. A novel ReHo component was found to distinguish PTSD and trauma-exposed controls, including the precuneus, IPL, middle frontal gyrus, middle occipital gyrus, and cerebellum. This study reveals that PTSD individuals exhibit intertwined functional and structural anomalies within the default mode network. Some alterations within this network may serve as a potential marker to distinguish between PTSD patients and trauma-exposed controls.

The Vestibulocerebellum and the Shattered Self: a Resting-State Functional Connectivity Study in Posttraumatic Stress Disorder and Its Dissociative Subtype

The flocculus is a region of the vestibulocerebellum dedicated to the coordination of neck, head, and eye movements for optimal posture, balance, and orienting responses. Despite growing evidence of vestibular and oculomotor impairments in the aftermath of traumatic stress, little is known about the effects of chronic psychological trauma on vestibulocerebellar functioning. Here, we investigated alterations in functional connectivity of the flocculus at rest among individuals with post-traumatic stress disorder (PTSD) and its dissociative subtype (PTSD + DS) as compared to healthy controls. Forty-four healthy controls, 57 PTSD, and 32 PTSD + DS underwent 6-min resting-state MRI scans. Seed-based functional connectivity analyses using the right and left flocculi as seeds were performed. These analyses revealed that, as compared to controls, PTSD and PTSD + DS showed decreased resting-state functional connectivity of the left flocculus with cortical regions involved in bodily self-consciousness, including the temporo-parietal junction, the supramarginal and angular gyri, and the superior parietal lobule. Moreover, as compared to controls, the PTSD + DS group showed decreased functional connectivity of the left flocculus with the medial prefrontal cortex, the precuneus, and the mid/posterior cingulum, key regions of the default mode network. Critically, when comparing PTSD + DS to PTSD, we observed increased functional connectivity of the right flocculus with the right anterior hippocampus, a region affected frequently by early life trauma. Taken together, our findings point toward the crucial role of the flocculus in the neurocircuitry underlying a coherent and embodied self, which can be compromised in PTSD and PTSD + DS.

The Cerebellum's Role in Affective Disorders: The Onset of Its Social Dimension

Major Depressive Disorder (MDD) and Bipolar Disorder (BD) are the most frequent mental disorders whose indeterminate etiopathogenesis spurs to explore new aetiologic scenarios. In light of the neuropsychiatric symptoms characterizing Cerebellar Cognitive Affective Syndrome (CCAS), the objective of this narrative review is to analyze the involvement of the cerebellum (Cbm) in the onset of these conditions. It aims at detecting the repercussions of the Cbm activities on mood disorders based on its functional subdivision in vestibulocerebellum (vCbm), pontocerebellum (pCbm) and spinocerebellum (sCbm). Despite the Cbm having been, for decades, associated with somato-motor functions, the described intercellular pathways, without forgiving the molecular impairment and the alteration in the volumetric relationships, make the Cbm a new important therapeutic target for MDD and BD. Given that numerous studies have showed its activation during mnestic activities and socio-emotional events, this review highlights in the Cbm, in which the altered external space perception (vCbm) is strictly linked to the cognitive-limbic Cbm (pCbm and sCbm), a crucial role in the MDD and BD pathogenesis. Finally, by the analysis of the cerebellar activity, this study aims at underlying not only the Cbm involvement in affective disorders, but also its role in social relationship building.

Cerebellar Prediction and Feeding Behaviour

Given the importance of the cerebellum in controlling movements, it might be expected that its main role in eating would be the control of motor elements such as chewing and swallowing. Whilst such functions are clearly important, there is more to eating than these actions, and more to the cerebellum than motor control. This review will present evidence that the cerebellum contributes to homeostatic, motor, rewarding and affective aspects of food consumption.Prediction and feedback underlie many elements of eating, as food consumption is influenced by expectation. For example, circadian clocks cause hunger in anticipation of a meal, and food consumption causes feedback signals which induce satiety. Similarly, the sight and smell of food generate an expectation of what that food will taste like, and its actual taste will generate an internal reward value which will be compared to that expectation. Cerebellar learning is widely thought to involve feed-forward predictions to compare expected outcomes to sensory feedback. We therefore propose that the overarching role of the cerebellum in eating is to respond to prediction errors arising across the homeostatic, motor, cognitive, and affective domains.

Self-supervised learning with application for infant cerebellum segmentation and analysis

Accurate tissue segmentation is critical to characterize early cerebellar development in the first two postnatal years. However, challenges in tissue segmentation arising from tightly-folded cortex, low and dynamic tissue contrast, and large inter-site data heterogeneity have limited our understanding of early cerebellar development. In this paper, we propose an accurate self-supervised learning framework for infant cerebellum segmentation. We validate its accuracy using 358 subjects from three datasets. Our results suggest the first six months exhibit the most rapid and dynamic changes, with gray matter (GM) playing a dominant role in cerebellar growth over white matter (WM). We also find both GM and WM volumes are larger in males than females, and GM and WM volumes are larger in autistic males than neurotypical males. Application of our method to a larger population will fuel more cerebellar studies, ultimately advancing our comprehension of its structure and function in neurotypical and disordered development.

Can the aberrant occipital-cerebellum network be a predictor of treatment in panic disorder?

BACKGROUND

This study aimed to detect altered brain activation pattern of patients with panic disorder (PD) and its changes after treatment. The possibilities of diagnosis and prediction of treatment response based on the aberrant brain activity were tested.

METHODS

Fifty-four PD patients and 54 healthy controls (HCs) were recruited. Clinical assessment and resting-state functional magnetic resonance imaging scans were conducted. Then, patients received a 4-week paroxetine treatment and underwent a second clinical assessment and scan. The fractional amplitude of low-frequency fluctuations (fALFF) was measured. Support vector machine (SVM) and support vector regression (SVR) analyses were conducted.

RESULTS

Lower fALFF values in the right calcarine/lingual gyrus and left lingual gyrus/cerebellum IV/V, whereas higher fALFF values in right cerebellum Crus II were observed in patients related to HCs at baseline. After treatment, patients with PD exhibited significant clinical improvement, and the abnormal lower fALFF values in the right lingual gyrus exhibited a great increase. The abnormal fALFF at pretreatment can distinguish patients from HCs with 80 % accuracy and predict treatment response which was reflected in the significant correlation between the predicted and actual treatment responses.

LIMITATIONS

The impacts of ethnic, cultural, and other regional differences on PD were not considered for it was a single-center study.

CONCLUSIONS

The occipital-cerebellum network played an important role in the pathophysiology of PD and should be a part of the fear network. The abnormal fALFF values in patients with PD at pretreatment could serve as biomarkers of PD and predict the early treatment response of paroxetine.

Risk factors of social anxiety in patients with essential tremor

OBJECTIVE

To study the risk factors of social anxiety (SA) in essential tremor (ET) patients.

METHODS

Motor, cognition, and SA were evaluated using the Fahn-Tolosa-Marin Tremor Rating Scale (FTMTRS), Mini-Mental State Examination (MMSE), and Liebowitz Social Anxiety Scale (LSAS) for each subject. The potential risk factors of SA in ET were analyzed using univariate analysis.

RESULTS

A total of 80 ET patients and 85 healthy controls completed the evaluation. The LSAS evaluation showed that the prevalence of SA in the ET group was 48.8%, higher than that in controls (12.9%, P < 0.001). Female (OR = 4.959, P = 0.014), younger age (OR = 4.172, P = 0.037), and head tremor (OR = 4.707, P = 0.025) were risk factors of SA among ET patients.

CONCLUSION

SA is prevalent in patients with ET. Risk factors, such as female sex, age, and head tremor, should be considered for the prevention and intervention of SA in ET patients.

The Role of the Cerebellar and Vestibular Networks in Anxiety Disorders and Depression: the Internal Model Hypothesis

Clinical data and animal studies confirmed that the cerebellum and the vestibular system are involved in emotions. Nowadays, no real consensus has really emerged to explain the clinical symptoms in humans and behavioral deficits in the animal models. We envisage here that the cerebellum and the vestibular system play complementary roles in emotional reactivity. The cerebellum integrates a large variety of exteroceptive and proprioceptive information necessary to elaborate and to update the internal model: in emotion, as in motor processes, it helps our body and self to adapt to the environment, and to anticipate any changes in such environment in order to produce a time-adapted response. The vestibular system provides relevant environmental stimuli (i.e., gravity, self-position, and movement) and is involved in self-perception. Consequently, cerebellar or vestibular disorders could generate « internal fake news» (due to lack or false sensory information and/or integration) that could, in turn, generate potential internal model deficiencies. In this case, the alterations provoke false anticipation of motor command and external sensory feedback, associated with unsuited behaviors. As a result, the individual becomes progressively unable to cope with the environmental solicitation. We postulate that chronically unsuited, and potentially inefficient, behavioral and visceral responses to environmental solicitations lead to stressful situations. Furthermore, this inability to adapt to the context of the situation generates chronic anxiety which could precede depressive states.

Zinc Deficiency Blunts the Effectiveness of Antidepressants in the Olfactory Bulbectomy Model of Depression in Rats

Currently used antidepressants do not always provide the desired results, and many patients suffer from treatment-resistant depression. Clinical studies suggest that zinc deficiency (ZnD) may be an important risk factor for depression and might blunt the effect of antidepressants. This study aimed to examine whether ZnD might blunt the effectiveness of antidepressants in the olfactory bulbectomy model (OB) of depression in rats. For this purpose, rats were subjected to the OB model, fed a zinc-deficient diet (3 mg Zn/kg) for 3 weeks, and finally treated with escitalopram (Esc), venlafaxine (Ven) 10 mg/kg, i.p., or combined Esc/Ven (1 mg/kg, i.p.) with zinc (5 mg/kg) for another 3 weeks. Open field (OFT), forced swim (FST), and sucrose intake (SIT) tests were used to evaluate depressive-like behavioral changes. In addition, serum, intracellular, and synaptic Zn concentrations and the level of zinc transporter (ZnT) proteins were analyzed. The OB + ZnD model induced hyperactivity in rats in the OFT, increased immobility time in the FST, and anhedonia in the SIT. Chronic treatment with Esc reduced immobility time in the FST in the OB + ZnD model. Esc/Ven +Zn increased sucrose intake in rats from the OB + ZnD group. The OB + ZnD decreased serum zinc levels and intracellular and synaptic Zn concentration in the prefrontal cortex (PFC) and cerebellum. These changes were normalized by chronic administration of Esc/Ven +Zn. Moreover, OB + ZnD decreased levels of the ZnT1 protein in the PFC and Hp and ZnT3 in Hp. Chronic administration of antidepressants did not alter the levels of ZnT proteins. The OB + ZnD model induces more depressive-like effects than either model alone. Our results show that ZnD may induce drug resistance in rats. Normalizing serum or brain zinc concentration is insufficient to reverse behavioral abnormalities caused by the OB + ZnD model. However, zinc supplementation might improve the effectiveness of antidepressants in reversing particular depression symptoms.

Acute-stress-induced change in salience network coupling prospectively predicts post-trauma symptom development

Substantial individual differences exist in how acute stress affects large-scale neurocognitive networks, including salience (SN), default mode (DMN), and central executive networks (CEN). Changes in the connectivity strength of these networks upon acute stress may predict vulnerability to long-term stress effects, which can only be tested in prospective longitudinal studies. Using such longitudinal design, we investigated whether the magnitude of acute-stress-induced functional connectivity changes (delta-FC) predicts the development of post-traumatic stress-disorder (PTSD) symptoms in a relatively resilient group of young police students that are known to be at high risk for trauma exposure. Using resting-state fMRI, we measured acute-stress-induced delta-FC in 190 police recruits before (baseline) and after trauma exposure during repeated emergency-aid services (16-month follow-up). Delta-FC was then linked to the changes in perceived stress levels (PSS) and post-traumatic stress symptoms (PCL and CAPS). Weakened connectivity between the SN and DMN core regions upon acute-stress induction at baseline predicted longitudinal increases in perceived-stress level but not of post-traumatic stress symptoms, whereas increased coupling between the overall SN and anterior cerebellum was observed in participants with higher clinician-rated PTSD symptoms, particularly intrusion levels. All the effects remained significant when controlling for trauma-exposure levels and cortisol-stress reactivity. Neither hormonal nor subjective measures exerted similar predictive or acquired effects. The reconfiguration of large-scale neural networks upon acute-stress induction is relevant for assessing and detecting risk and resilience factors for PTSD. This study highlights the SN connectivity-changes as a potential marker for trauma-related symptom development, which is sensitive even in a relatively resilient sample.

Decreased Functional Connectivity of Vermis-Ventral Prefrontal Cortex in Bipolar Disorder

Objectives: To investigate changes in functional connectivity between the vermis and cerebral regions in the resting state among subjects with bipolar disorder (BD).

Methods: Thirty participants with BD and 28 healthy controls (HC) underwent the resting state functional magnetic resonance imaging (fMRI). Resting-state functional connectivity (rsFC) of the anterior and posterior vermis was examined. For each participant, rsFC maps of the anterior and posterior vermis were computed and compared across the two groups.

Results: rsFC between the whole vermis and ventral prefrontal cortex (VPFC) was significantly lower in the BD groups compared to the HC group, and rsFC between the anterior vermis and the middle cingulate cortex was likewise significantly decreased in the BD group.

Limitations: 83.3% of the BD participants were taking medication at the time of the study. Our findings may in part be attributed to treatment differences because we did not examine the effects of medication on rsFC. Further, the mixed BD subtypes in our current study may have confounding effects influencing the results.

Conclusions: These rsFC differences of vermis-VPFC between groups may contribute to the BD mood regulation.

Out of control: An altered parieto-occipital-cerebellar network for impulsivity in bipolar disorder

Bipolar disorder is an affective disorder characterized by rapid fluctuations in mood ranging from episodes of depression to mania, as well as by increased impulsivity. Previous studies investigated the neural substrates of bipolar disorder mainly using univariate methods, with a particular focus on the neural circuitry underlying emotion regulation difficulties. In the present study, capitalizing on an innovative whole-brain multivariate method to structural analysis known as Source-based Morphometry, we investigated the neural substrates of bipolar disorder and their relation with impulsivity, assessed with both self-report measures and performance-based tasks. Structural images from 46 patients with diagnosis of bipolar disorder and 60 healthy controls were analysed. Compared to healthy controls, patients showed decreased gray matter concentration in a parietal-occipital-cerebellar network. Notably, the lower the gray matter concentration in this circuit, the higher the self-reported impulsivity. In conclusion, we provided new evidence of an altered brain network in bipolar disorder patients related to their abnormal impulsivity. Taken together, these findings extend our understanding of the neural and symptomatic characterization of bipolar disorder.

Altered dynamic parahippocampus functional connectivity in patients with post-traumatic stress disorder

OBJECTIVES

This study investigated dynamic brain functional alterations in post-traumatic stress disorder (PTSD) patients with resting state functional magnetic resonance imaging.

METHODS

Degree centrality (DC) and seed-based functional connectivity (FC) analyses were conducted among typhoon survivours with (n = 27) and without PTSD (n = 33) and healthy controls (HC) (n = 30) to assess the intrinsic dysconnectivity pattern and network-level brain function.

RESULTS

Both the PTSD group and the trauma-exposed control (TEC) group had increased DC in the left parahippocampal gyrus relative to the HC group. More increased DC in the left parahippocampal gyrus was found in the PTSD group. Both traumatised groups exhibited decreased left parahippocampal gyrus dynamic FC with the bilateral middle frontal gyrus and superior frontal gyrus relative to the HC group. The Checklist-Civilian Version score was positively correlated with dynamic FC between the parahippocampal gyrus and left superior frontal gyrus but was negatively correlated with dynamic FC between the parahippocampal gyrus and right middle frontal gyrus.

CONCLUSIONS

Trauma exposure may lead to an altered dynamic FC in individuals with or without PTSD. An altered DC in the parahippocampal gyrus may be an important risk factor for PTSD development following trauma exposure. A more prominently increased DC in the parahippocampal gyrus might be a common trait in the PTSD group.

Integrating Genomic and Transcriptomic Data to Reveal Genetic Mechanisms Underlying Piao Chicken Rumpless Trait

Piao chicken, a rare Chinese native poultry breed, lacks primary tail structures, such as pygostyle, caudal vertebra, uropygial gland, and tail feathers. So far, the molecular mechanisms underlying tail absence in this breed remain unclear. In this study, we comprehensively employed comparative transcriptomic and genomic analyses to unravel potential genetic underpinnings of rumplessness in Piao chicken. Our results reveal many biological factors involved in tail development and several genomic regions under strong positive selection in this breed. These regions contain candidate genes associated with rumplessness, including Irx4, Il18, Hspb2, and Cryab. Retrieval of quantitative trait loci (QTL) and gene functions implies that rumplessness might be consciously or unconsciously selected along with the high-yield traits in Piao chicken. We hypothesize that strong selection pressures on regulatory elements might lead to changes in gene activity in mesenchymal stem cells of the tail bud. The ectopic activity could eventually result in tail truncation by impeding differentiation and proliferation of the stem cells. Our study provides fundamental insights into early initiation and genetic basis of the rumpless phenotype in Piao chicken.

The spontaneous brain activity of disgust: Perspective from resting state fMRI and resting state EEG

In recent years, more and more studies on disgust have shown the association between disgust and various psychopathologies. Revealing the spontaneous brain activity patterns associated with disgust sensitivity from the perspective of individual differences will give us an insight into the neurologic nature of disgust and its psychopathological vulnerability. Here, we used two modal brain imaging techniques (resting fMRI and resting EEG) to reveal spontaneous brain activity patterns closely related to disgust sensitivity. The amplitude of low-frequency fluctuation results showed that disgust sensitivity is negatively correlated with the spontaneous activity of the right cerebellum crus II and positively correlated with the spontaneous activity of the right superior frontal cortex, which are inhibition-related brain regions. Furthermore, the microstate results of rest EEG indicated that the corrected duration, occurrence rate, and contribution of Class C, which is related to the anterior default mode network and is considered to be related to subjective representation of one' own body by combining interoceptive information with affective salience, were significantly positively correlated with the disgust sensitivity level. This data-driven approach provides the first evidence on the intrinsic brain features of disgust sensitivity based on two resting-state brain modalities. The results represent an initial effort to uncover the neurological basis of disgust sensitivity and its connection to psychopathology.

The neural correlates of paternal consoling behavior and frustration in response to infant crying

Human fathers often form strong attachments to their infants that contribute to positive developmental outcomes. However, fathers are also the most common perpetrators of infant abuse, and infant crying is a known trigger. Research on parental brain responses to infant crying have typically employed passive listening paradigms. However, parents usually engage with crying infants. Therefore, we examined the neural responses of 20 new fathers to infant cries both while passively listening, and while actively attempting to console the infant by selecting soothing strategies in a video game format. Compared with passive listening, active responding robustly activated brain regions involved in movement, empathy and approach motivation, and deactivated regions involved in stress and anxiety. Fathers reporting more frustration had less activation in basal forebrain areas and in brain areas involved with emotion regulation (e.g., prefrontal cortex and the supplementary motor area). Successful consolation of infant crying activated regions involved in both action-outcome learning and parental caregiving (anterior and posterior cingulate cortex). Overall, results suggest that active responding to infant cries amplifies activation in many brain areas typically activated during passive listening. Additionally, paternal frustration during active responding may involve a combination of low approach motivation and low engagement of emotion regulation.

Human Chemosignals and Brain Activity: A Preliminary Meta-analysis of the Processing of Human Body Odors

Across phyla, chemosignals are a widely used form of social communication and increasing evidence suggests that chemosensory communication is present also in humans. Chemosignals can transfer, via body odors, socially relevant information, such as specific information about identity or emotional states. However, findings on neural correlates of processing of body odors are divergent. The aims of this meta-analysis were to assess the brain areas involved in the perception of body odors (both neutral and emotional) and the specific activation patterns for the perception of neutral body odor (NBO) and emotional body odor (EBO). We conducted an activation likelihood estimation (ALE) meta-analysis on 16 experiments (13 studies) examining brain activity during body odors processing. We found that the contrast EBO versus NBO resulted in significant convergence in the right middle frontal gyrus and the left cerebellum, whereas the pooled meta-analysis combining all the studies of human odors showed significant convergence in the right inferior frontal gyrus. No significant cluster was found for NBOs. However, our findings also highlight methodological heterogeneity across the existing literature. Further neuroimaging studies are needed to clarify and support the existing findings on neural correlates of processing of body odors.

Cerebral Cortical Activity Following Non-invasive Cerebellar Stimulation-a Systematic Review of Combined TMS and EEG Studies

The cerebellum sends dense projections to both motor and non-motor regions of the cerebral cortex via the cerebellarthalamocortical tract. The integrity of this tract is crucial for healthy motor and cognitive function. This systematic review examines research using transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) to the cerebellum with combined cortical electroencephalography (EEG) to explore the temporal features of cerebellar-cortical connectivity. A detailed discussion of the outcomes and limitations of the studies meeting review criteria is presented. Databases were searched between 1 December 2017 and 6 December 2017, with Scopus alerts current as of 23 July 2019. Of the 407 studies initially identified, 10 met review criteria. Findings suggested that cerebellar-cortical assessment is suited to combined TMS and EEG, although work is required to ensure experimental procedures are optimal for eliciting a reliable cerebellar response from stimulation. A distinct variation in methodologies and outcome measures employed across studies, and small sample sizes limited the conclusions that could be drawn regarding the electrophysiological signatures of cerebellar-cortical communication. This review highlights the need for stringent protocols and methodologies for cerebellar-cortical assessments via combined TMS and EEG. With these in place, combined TMS and EEG will provide a valuable means for exploring cerebellar connectivity with a wide range of cortical sites. Assessments have the potential to aid in the understanding of motor and cognitive function in both healthy and clinical groups, and provide insights into long-range neural communication generally.

Disrupted dynamic functional connectivity in right amygdalar subregions differentiates bipolar disorder from major depressive disorder

Notwithstanding being the object of a growing field of clinical research, the investigation of the dynamic resting-state functional connectivity alterations in psychiatric illnesses is still in its early days. Current research on major depressive disorder (MDD) and bipolar disorder (BD) has evidenced abnormal resting-state functional connectivity (rsFC), especially in regions subserving emotional processing and regulation such as the amygdala. However, dynamic changes in functional connectivity within the amygdalar subregions in distinguishing BD and MDD has not yet been fully understood. In this paper, we aim at analyzing the patterns characterizing dynamic FC (dFC) in the right amygdala to investigate the differences between similarly depressed BD and MDD. A number of 40 BD patients, 61 MDD patients and 63 healthy controls (HCs) underwent functional magnetic resonance imaging (fMRI) at rest. Using the right-amygdala as seed region, we compared the dFC within three subdivisions, namely, laterobasal (LB), centromedial (CM) and superficial (SF) between all the groups. To do so, one-way ANOVA followed by post-hoc t-tests were employed. Compared to HCs, patients with BD had a decreased dFC between right LB and the left postcentral gyrus as well as an increased dFC between right CM and the right cerebellum.Compared to BD patients, patients with MDD showed a decreased dFC between right CM and the cerebellum and an increased dFC between right LB and the left postcentral gyrus. These findings present initial evidence that abnormal patterns of the right-amygdalar subregions shared by BD and MDD supports the differential pathophysiology of these disorders.

The Anatomical and Functional Heterogeneity of the Mediodorsal Thalamus

The mediodorsal nucleus (MD) represents just one piece of a complex relay structure situated within the brain, called the thalamus. MD is characterized by its robust interconnections with other brain areas, especially with limbic-related structures. Given the close anatomo-functional relationship between the MD and the limbic system, this particular thalamic nucleus can directly influence various affective behaviors and participate in cognition. In this work, we review data collected from multiple anatomical studies conducted in rodent, human, and non-human primates, highlighting the complexity of this structure and of the neural networks in which it takes part. We provide proof that the MD is involved in the unification of several anatomical structures, being able to process the information and influence the activity in numerous cortical and subcortical neural circuits. Moreover, we uncover intrinsic and extrinsic mechanisms that offer MD the possibility to execute and control specific high functions of the nervous system. The collected data indicate the great importance of the MD in the limbic system and offer relevant insight into the organization of thalamic circuits that support MD functions.

Psychiatric Disturbance or Parkinsonism as a Presentation of CNS Lymphoma: Observational Retrospective Study and Review of Literature

OBJECTIVE

To evaluate the incidence of and characterize the presentation of neuropsychiatric symptoms and/or Parkinsonism as a presentation of central nervous system lymphoma (CNSL) in either its primary CNSL form or when it spreads to the brain in systemic diffuse large B-cell lymphoma (secondary CNSL).

PATIENTS AND METHODS

With Institutional Review Board approval we identified patients who had been treated at Mayo Clinic from 1998 to 2018 and were recorded to have a combination of ICD 9/10 codes for CNSL and various psychiatric diagnoses.

RESULTS

A total of 20 of the 232 patients (9%) were noted to have neuropsychiatric symptoms preceding diagnosis. The average age at diagnosis was 62, with even split for sex. The majority (85%) of patients had primary CNSL. The average duration of symptoms before the diagnosis was 4.8 months. Confusion (80%), depression (40%), apathy (30%), anxiety (30%), and agitation (30%) were the most common symptoms identified. The majority (65%) of patients had subcortical lesions followed by the frontal lobe (50%). Parkinsonism was identified in 5 of the 20 patients with 4 demonstrating resolution of symptoms with treatment of the lymphoma.

CONCLUSIONS

Neuropsychiatric symptoms are a rare but notable symptom before the presentation of CNSL. There is an increasing awareness of neurological illness presenting as pure psychiatric disturbance, prompting the need to exclude organic and treatable diseases, particularly in elderly patients. Acknowledgment and diagnosis are important for an appropriate management as there is a significant impact on patient and caregiver quality of life.

Deep Cerebellar Nuclei Segmentation via Semi-Supervised Deep Context-Aware Learning from 7T Diffusion MRI

Deep cerebellar nuclei are a key structure of the cerebellum that are involved in processing motor and sensory information. It is thus a crucial step to accurately segment deep cerebellar nuclei for the understanding of the cerebellum system and its utility in deep brain stimulation treatment. However, it is challenging to clearly visualize such small nuclei under standard clinical magnetic resonance imaging (MRI) protocols and therefore precise segmentation is not feasible. Recent advances in 7 Tesla (T) MRI technology and great potential of deep neural networks facilitate automatic patient-specific segmentation. In this paper, we propose a novel deep learning framework (referred to as DCN-Net) for fast, accurate, and robust patient-specific segmentation of deep cerebellar dentate and interposed nuclei on 7T diffusion MRI. DCN-Net effectively encodes contextual information on the patch images without consecutive pooling operations and adding complexity via proposed dilated dense blocks. During the end-to-end training, label probabilities of dentate and interposed nuclei are independently learned with a hybrid loss, handling highly imbalanced data. Finally, we utilize self-training strategies to cope with the problem of limited labeled data. To this end, auxiliary dentate and interposed nuclei labels are created on unlabeled data by using DCN-Net trained on manual labels. We validate the proposed framework using 7T B0 MRIs from 60 subjects. Experimental results demonstrate that DCN-Net provides better segmentation than atlas-based deep cerebellar nuclei segmentation tools and other state-of-the-art deep neural networks in terms of accuracy and consistency. We further prove the effectiveness of the proposed components within DCN-Net in dentate and interposed nuclei segmentation.

The Role of Astrocytes in the Development of the Cerebellum

Astrocytes, initially described as merely support cells, are now known as a heterogeneous population of cells actively involved in a variety of biological functions such as: neuronal migration and differentiation; regulation of cerebral blood flow; metabolic control of extracellular potassium concentration; and modulation of synapse formation and elimination; among others. Cerebellar glial cells have been shown to play a significant role in proliferation, differentiation, migration, and synaptogenesis. However, less evidence is available about the role of neuron-astrocyte interactions during cerebellar development and their impact on diseases of the cerebellum. In this review, we will focus on the mechanisms underlying cellular interactions, specifically neuron-astrocyte interactions, during cerebellar development, function, and disease. We will discuss how cerebellar glia, astrocytes, and Bergmann glia play a fundamental role in several steps of cerebellar development, such as granule cell migration, axonal growth, neuronal differentiation, and synapse formation, and in diseases associated with the cerebellum. We will focus on how astrocytes and thyroid hormones impact cerebellar development. Furthermore, we will provide evidence of how growth factors secreted by glial cells, such as epidermal growth factor and transforming growth factors, control cerebellar organogenesis. Finally, we will argue that glia are a key mediator of cerebellar development and that identification of molecules and pathways involved in neuron-glia interactions may contribute to a better understanding of cerebellar development and associated disorders.

Changes in functional connectivity with cognitive behavioral therapy for social anxiety disorder predict outcomes at follow-up

Approximately half of individuals with Social Anxiety Disorder (SAD) treated with psychological intervention do not achieve clinically significant improvement or retain long-term gains. Neurobiological models of SAD propose that disruptions in functioning of amygdala-prefrontal circuitry is implicated in short-term treatment response. However, whether treatment-related changes in functional connectivity predict long-term well-being after psychotherapy is unknown. Patients with SAD completed an incidental emotion regulation task during fMRI before and after treatment with cognitive behavioral therapy or acceptance and commitment therapy (n = 23, collapsed across groups). Psychophysiological interaction analyses using amygdala seed regions were conducted to assess changes in functional connectivity from pre-to post-treatment that predicted symptom change from 6 to 12-month follow-up. Negative change (i.e., greater inverse/weaker positive) in amygdala connectivity with the dorsomedial prefrontal cortex (dmPFC) and dorsal anterior cingulate cortex (dACC) predicted greater symptom reduction during follow-up. Positive change in amygdala connectivity with the cerebellum, fusiform gyrus, and pre-central and post-central gyri predicted less symptom reduction (e.g., no change or worsening). Results suggest that strengthened amygdala connectivity with regulatory regions may promote better long-term outcomes, whereas changes with visual and sensorimotor regions may represent sensitization to emotion-related cues, conferring poorer outcomes. Clinical implications for treatment personalization are discussed, should effects replicate in larger samples.

Tremor Distribution and the Variable Clinical Presentation of Essential Tremor

In addition to having postural and kinetic tremor of the upper limbs, some patients with essential tremor (ET) may have head tremor as well as cognitive and psychiatric disorders. We aimed to investigate whether the variable clinical presentation in ET patients, including motor and non-motor symptoms, differs in patients with and without head tremor. We consecutively enrolled 70 patients with a diagnosis of ET. Tremor severity was assessed by means of clinical rating scales. Patients also underwent kinematic recordings of postural and kinetic tremor of the upper limbs based on an optoelectronic system. Several neuropsychological tests were also administered. Finally, we adopted the structured interviews for DSM-IV, SCID-I, and SCID-II to investigate psychiatric and personality disorders. ET patients with upper limb tremor plus head tremor exhibited more severe kinetic tremor of the upper limbs and a higher occurrence of axis I psychiatric disorders than ET patients with upper limb tremor only. Cognitive and other motor and psychiatric features did not differ significantly with respect to tremor distribution. The study findings support the hypothesis that body tremor distribution, i.e., the presence of head tremor, influences the variable clinical presentation of ET. The study results support the notion that cases with head tremor may represent a distinct ET subtype, characterized by a prominent cerebellar involvement, and that psychiatric disorders should be considered as a specific manifestation of ET.

Reduced gray matter volume and cortical thickness associated with traffic-related air pollution in a longitudinally studied pediatric cohort

Early life exposure to air pollution poses a significant risk to brain development from direct exposure to toxicants or via indirect mechanisms involving the circulatory, pulmonary or gastrointestinal systems. In children, exposure to traffic related air pollution has been associated with adverse effects on cognitive, behavioral and psychomotor development. We aimed to determine whether childhood exposure to traffic related air pollution is associated with regional differences in brain volume and cortical thickness among children enrolled in a longitudinal cohort study of traffic related air pollution and child health. We used magnetic resonance imaging to obtain anatomical brain images from a nested subset of 12 year old participants characterized with either high or low levels of traffic related air pollution exposure during their first year of life. We employed voxel-based morphometry to examine group differences in regional brain volume, and with separate analyses, changes in cortical thickness. Smaller regional gray matter volumes were determined in the left pre- and post-central gyri, the cerebellum, and inferior parietal lobe of participants in the high traffic related air pollution exposure group relative to participants with low exposure. Reduced cortical thickness was observed in participants with high exposure relative to those with low exposure, primarily in sensorimotor regions of the brain including the pre- and post-central gyri and the paracentral lobule, but also within the frontal and limbic regions. These results suggest that significant childhood exposure to traffic related air pollution is associated with structural alterations in brain.

Metabolism of Amino Acids in the Brain and Their Roles in Regulating Food Intake

Amino acids (AAs) and their metabolites play an important role in neurological health and function. They are not only the building blocks of protein but are also neurotransmitters. In the brain, glutamate and aspartate are the major excitatory neurotransmitters, whereas γ-aminobutyrate (GABA, a metabolite of glutamate) and glycine are the major inhibitory neurotransmitters. Nitric oxide (NO, a metabolite of arginine), H₂S (a metabolite of cysteine), serotonin (a metabolite of tryptophan) and histamine (a metabolite of histidine), as well as dopamine and norepinephrine (metabolites of tyrosine) are neurotransmitters to modulate synaptic plasticity, neuronal activity, learning, motor control, motivational behavior, emotion, and executive function. Concentrations of glutamine (a precursor of glutamate and aspartate), branched-chain AAs (precursors of glutamate, glutamine and aspartate), L-serine (a precursor of glycine and D-serine), methionine and phenylalanine in plasma are capable of affecting neurotransmission through the syntheses of glutamate, aspartate, and glycine, as well as the competitive transport of tryptophan and tyrosine across from the blood-brain barrier. Adequate consumption of AAs is crucial to maintain their concentrations and the production of neurotransmitters in the central nervous system. Thus, the content and balance of AAs in diets have a profound impact on food intake by animals. Knowledge of AA transport and metabolism in the brain is beneficial for improving the health and well-being of humans and animals.

Association of Cerebral Artery Stenosis With Post-stroke Depression at Discharge and 3 Months After Ischemic Stroke Onset

Background: Post-stroke depression (PSD) is one of the most common complications after stroke, which seriously affects patients' recovery outcome. Although vascular depression has been extensively studied, the relationship between cerebral artery stenosis and PSD has not been clarified so far. Methods: Two hundred ninety-eight patients with ischemic stroke (72 women, 226 men) with computed tomography angiography (CTA) or magnetic resonance angiography (MRA) were included in this study. Cerebral artery stenosis ≥50% was used as the cut-off value. The DSM-V diagnostic criteria of PSD was met and the 17-item Hamilton Rating Scale for Depression (HAMD-17) score over 7 at discharge and 3 months after stroke onset was regarded as the primary outcome. The χ²-test, Mann-Whitney U-test, and t-test were used to check for statistical significance. Results: At discharge, Barthel index (p < 0.001), left middle cerebral artery stenosis (p = 0.019), drinking history (p = 0.048), basilar artery stenosis (p = 0.037) were significantly associated with PSD. At 3 months after ischemic stroke onset, Barthel index (p = 0.011), left middle cerebral artery stenosis (p = 0.012), female gender (p = 0.001) were significantly associated with PSD. Conclusions: The findings demonstrated that left middle cerebral artery and basilar artery stenosis are associated with PSD. It was suggested that cerebral artery stenosis was a risk factor of PSD and should be recognized and intervened early. Registration Number: ChiCTR-ROC-17013993.

Neurological Soft Signs and Post-Traumatic Stress Disorder: A Biomarker of Severity?

BACKGROUND

The psychophysiological changes for individual suffering from chronic post-traumatic stress disorder (PTSD) raise to the questions of how facilitate recovery and return to work. Negative alterations in neuro-cognition remain a complaint for patients and participate to long-term functional impairments. Neurological soft signs (NSSs) appear as a candidate for better understanding these complaints. They have been reported in several mental disorders. They are found in several behavioral and/or neurocognitive disorders and are taken into account by psychiatric rehabilitation programs to support recovery. As few studies evaluate NSSs in PTSD, our exploratory study aims to assess NSSs in chronic PTSD and their relationships with PTSD severity.

METHOD

Twenty-two patients with a clinical diagnosis of chronic PTSD were evaluated in terms of PTSD severity (post-traumatic checklist scale, PCL5), NSSs (NSSs psychomotor skills scale, PASS), and well-being upon arrival to the hospital and compared with 15 healthy subjects. Statistical non-parametric analyses assessed the relationships between these variables.

RESULTS

PTSD subjects exhibited higher NSSs compared with healthy subjects. NSSs were positively associated with PTSD severity, with negative alterations in cognition and mood, and with impairment in well-being. They were higher in women compared with men. No impact of age was found. Three groups were identified based on the severity of the PTSD. Severe PTSD exhibited NSSs characterized by motor integration alterations.

CONCLUSIONS

This pilot study suggests that NSSs might be a biomarker of PTSD severity. This proof of concept highlights the need for further research for better evaluating the clinical neuro-functional impairment. This will be helping for defining neurological remediation for promoting PTSD recovery.

Is the Cerebellum Involved in the Nervous Control of the Immune System Function?

BACKGROUND

According to the views of psychoneuroendocrinoimmunology, many interactions exist between nervous, endocrine and immune system the purpose of which is to achieve adaptive measures restoring an internal equilibrium (homeostasis) following stress conditions. The center where these interactions converge is the hypothalamus. This is a center of the autonomic nervous system that controls the visceral systems, including the immune system, through both the nervous and neuroendocrine mechanisms. The nervous mechanisms are based on nervous circuits that bidirectionally connect hypothalamic neurons and neurons of the sympathetic and parasympathetic system; the neuroendocrine mechanisms are based on the release by neurosecretory hypothalamic neurons of hormones that target the endocrine cells and on the feedback effects of the hormones secreted by these endocrine cells on the same hypothalamic neurons. Moreover, the hypothalamus is an important subcortical center of the limbic system that controls through nervous and neuroendocrine mechanisms the areas of the cerebral cortex where the psychic functions controlling mood, emotions, anxiety and instinctive behaviors take place. Accordingly, various studies conducted in the last decades have indicated that hypothalamic diseases may be associated with immune and/or psychic disorders.

OBJECTIVE

Various researches have reported that the hypothalamus is controlled by the cerebellum through a feedback nervous circuit, namely the hypothalamocerebellar circuit, which bi-directionally connects regions of the hypothalamus, including the immunoregulatory ones, and related regions of the cerebellum. An objective of the present review was to analyze the anatomical bases of the nervous and neuroendocrine mechanisms for the control of the immune system and, in particular, of the interaction between hypothalamus and cerebellum to achieve the immunoregulatory function.

CONCLUSION

Since the hypothalamus represents the link through which the immune functions may influence the psychic functions and vice versa, the cerebellum, controlling several regions of the hypothalamus, could be considered as a primary player in the regulation of the multiple functional interactions postulated by psychoneuroendocrinoimmunology.

Psychosocial factors and perceived tremor disability in essential tremor

Growing evidence suggests that patients with essential tremor (ET) show impairment in psychosocial functions and subsequently increasing vulnerability to anxiety. Here we review evidence supporting a positive relationship between self-reported motor disability and psychological symptoms in ET and critically analyze evidence suggesting how psychosocial factors enhance tremor disability in ET. Theories related to motor competency, behavioral conditioning, and social anxiety have been proposed to relate self-concepts to self-reported tremor disability. We review these theories and then propose a new model in an effort to focus on the self-concepts among ET patients as a factor in tremor disability. Patients with ET exhibited cognitive abnormalities, depression, anxiety, and a higher prevalence of avoidant personality types. Although anxiety, depression and personality types may influence tremor disability in ET, self-concepts may better explain perceived tremor disability in social situations. We conclude by discussing a proposed biopsychosocial model and suggesting future research on ET specific assessment tools and intervention methods.

The neural substrates responsible for how trait anxiety affects delay discounting: Right hippocampal and cerebellar connectivity with bistable right inferior parietal lobule

Delay discounting, an indicator of impulsivity, refers to the extent of devaluing future rewards. Studies have found that individuals with trait anxiety generally depreciate the later larger rewards, showing steeper delay discounting rates. However, little is known about the neural substrates responsible for how trait anxiety affects individuals' delay discounting. To address this question, we employed the voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) methods to explore the neural substrates of trait anxiety responsible for delay discounting. Behavioral results showed that trait anxiety was significantly positively correlated with delay discounting rates. The VBM analysis revealed that gray matter volumes of the right hippocampus (RHPC) and right cerebellum (RCere) were significantly positively correlated with trait anxiety. Moreover, the RSFC results showed that bistable right inferior parietal lobule (RIPL) connectivity with the RHPC and RCere were all inversely associated with trait anxiety. More importantly, mediation analysis indicated that trait anxiety played a completely mediating role in the relation between functional connectivity of RHPC-RIPL and RCere-RIPL and delay discounting. These results suggested that bistable RIPL connectivity with RHPC and RCere could be neural substrates underlying the effect of trait anxiety on delay discounting. On the whole, the current study yields insights into how trait anxiety affects delay discounting and provides a novel account from a neural basis perspective.

Cerebellar fastigial nucleus is involved in post-stroke depression through direct cerebellar-hypothalamic GABAergic and glutamatergic projections

The present study aimed to investigate whether the cerebellar fastigial nucleus (FN) is involved in post-stroke depression (PSD), and to observe the effect of direct cerebellar-hypothalamic γ-aminobutyric acid (GABA)ergic and glutamatergic projections on PSD, in order to understand the mechanisms underlying the cerebellar modulation of mood and emotion. Healthy Sprague-Dawley rats were randomly divided into five groups: Sham-operated, Stroke, PSD, FN lesion, and decussation of superior cerebellar peduncle (XSCP) lesion groups. Sham surgery was performed in animals of the Sham group (n=6). The rats in the other four groups (n=6 for each group) underwent middle cerebral artery occlusion. The rats were examined twice a week in an open field test. In addition, the expression of cytokines in hippocampal tissues, and the content of glutamate and GABA in the lateral hypothalamic area (LHA) were measured. The results showed that scores corresponding to the behavioral signs of depression were decreased in the PSD, FN lesion and XSCP lesion groups. In addition, the mRNA levels of tumor necrosis factor-α, interleukin (IL)-6, and IL-1β in the hippocampus of the PSD, FN lesion and XSCP lesion groups were significantly increased. The GABA and glutamate content in the LHA were also decreased significantly in the PSD, FN lesion and XSCP lesion groups. Taken together, the findings of the present study indicated that the cerebellar FN may be involved in PSD through the direct cerebellar-hypothalamic glutamatergic and GABAergic projections.

Detecting Brain Activity Following a Verbal Command in Patients With Disorders of Consciousness

Background

The accurate assessment of patients with disorders of consciousness (DOC) is a challenge to most experienced clinicians. As a potential clinical tool, functional magnetic resonance imaging (fMRI) could detect residual awareness without the need for the patients’ actual motor responses.

Methods

We adopted a simple active fMRI motor paradigm (hand raising) to detect residual awareness in these patients. Twenty-nine patients were recruited. They met the diagnosis of minimally conscious state (MCS) (male = 6, female = 2; n = 8), vegetative state/unresponsive wakefulness syndrome (VS/UWS) (male = 17, female = 4; n = 21).

Results

We analyzed the command-following responses for robust evidence of statistically reliable markers of motor execution, similar to those found in 15 healthy controls. Of the 29 patients, four (two MCS, two VS/UWS) could adjust their brain activity to the “hand-raising” command, and they showed activation in motor-related regions (which could not be discovered in the own-name task).

Conclusion

Longitudinal behavioral assessments showed that, of these four patients, two in a VS/UWS recovered to MCS and one from MCS recovered to MCS+ (i.e., showed command following). In patients with no response to hand raising task, six VS/UWS and three MCS ones showed recovery in follow-up procedure. The simple active fMRI “hand-raising” task can elicit brain activation in patients with DOC, similar to those observed in healthy volunteers. Activity of the motor-related network may be taken as an indicator of high-level cognition that cannot be discerned through conventional behavioral assessment.

The neural correlates of hedonic and eudaimonic happiness: An fMRI study

The current study investigated the neural correlates of both hedonic and eudaimonic happiness. Seventeen students underwent fMRI while cued with written sentences describing three classes of life events: Hedonic events (HE), eudaimonic events (EE) and neutral events (NE). We asked participants to imagine and empathize with all these event types. Results showed that, compared to NE, both HE and EE activated a network involving frontal, temporal and parietal regions, as well as subcortical structures. However, in the HE/EE comparison, HE showed enhanced activity in frontal medial/middle regions and anterior cingulate cortex; by contrast, EE showed increased activity in the right precentral gyrus. Findings suggest that hedonic and eudaimonic happiness activate similar neural correlates. However, both kinds of happiness are also associated with distinctive brain areas serving distinctive functions.

Individualized prediction of dispositional worry using white matter connectivity

BACKGROUND

Excessive worry is a defining feature of generalized anxiety disorder and is present in a wide range of other psychiatric conditions. Therefore, individualized predictions of worry propensity could be highly relevant in clinical practice, with respect to the assessment of worry symptom severity at the individual level.

METHODS

We applied a multivariate machine learning approach to predict dispositional worry based on microstructural integrity of white matter (WM) tracts.

RESULTS

We demonstrated that the machine learning model was able to decode individual dispositional worry scores from microstructural properties in widely distributed WM tracts (mean absolute error = 10.46, p < 0.001; root mean squared error = 12.82, p < 0.001; prediction R2 = 0.17, p < 0.001). WM tracts that contributed to worry prediction included the posterior limb of internal capsule, anterior corona radiate, and cerebral peduncle, as well as the corticolimbic pathways (e.g. uncinate fasciculus, cingulum, and fornix) already known to be critical for emotion processing and regulation.

CONCLUSIONS

The current work thus elucidates potential neuromarkers for clinical assessment of worry symptoms across a wide range of psychiatric disorders. In addition, the identification of widely distributed pathways underlying worry propensity serves to better improve the understanding of the neurobiological mechanisms associated with worry.

Salience Network Disruption in U.S. Army Soldiers With Posttraumatic Stress Disorder

Background

Better understanding of the neurobiology of posttraumatic stress disorder (PTSD) may be critical to developing novel, effective therapeutics. Here, we conducted a data-driven investigation using a well-established, graph-based topological measure of nodal strength to determine the extent of functional dysconnectivity in a cohort of active duty U.S. Army soldiers with PTSD compared to controls.

Methods

A total of 102 participants with (n = 50) or without PTSD (n = 52) completed functional magnetic resonance imaging at rest and during symptom provocation using subject-specific script imagery. Vertex/voxel global brain connectivity with global signal regression (GBCr), a measure of nodal strength, was calculated as the average of its functional connectivity with all other vertices/voxels in the brain gray matter.

Results

In contrast to resting state, where there were no group differences, we found a significantly higher GBCr during symptom provocation, in PTSD participants compared to controls, in areas within the right hemisphere, including anterior insula, caudal-ventrolateral prefrontal, and rostral-ventrolateral parietal cortices. Overall, these clusters overlapped with the ventral and dorsal salience networks. Post hoc analysis showed increased GBCr in these salience clusters during symptom provocation compared to resting state. In addition, resting-state GBCr in the salience clusters predicted GBCr during symptom provocation in PTSD participants but not in controls.

Conclusion

In PTSD, increased connectivity within the salience network has been previously hypothesized, based primarily on seed-based connectivity findings. The current results strongly support this hypothesis using whole-brain network measure in a fully data-driven approach. It remains to be seen in future studies whether these identified salience disturbances would normalize following treatment.