Valerie Voon

University of Cambridge | Cam

Background Structural imaging holds great potential for precise targeting and stimulation for deep brain stimulation (DBS). The anatomical information it provides may serve as potential biomarkers for predicting the efficacy of DBS in treatment-resistant depression (TRD). Aims The primary aim is to identify preoperative imaging biomarkers that cor...

Objective: Personalized transcranial magnetic stimulation (TMS) targeting, guided by functional connectivity (FC), shows potential in treating depression. The present study aims to map individual FC peak location using UK Biobank, to evaluate individual differences and reproducibility of FC-based targets. Methods: We analyzed UK Biobank resting-sta...

The Deep Brain Stimulation (DBS) Think Tank XI was held on August 9–11, 2023 in Gainesville, Florida with the theme of “Pushing the Forefront of Neuromodulation”. The keynote speaker was Dr. Nico Dosenbach from Washington University in St. Louis, Missouri. He presented his research recently published in Nature inn a collaboration with Dr. Evan Gord...

Objectives/Aims The bed nucleus of the stria terminalis (BNST), considered a part of ‘extended amygdala’ and located in the basomedial forebrain, is characterized by its connections with other limbic structures, hypothalamic and brainstem nuclei. With these crucial connections, it plays a key role in emotional processing and modulation of autonomic...

Objectives Waiting and stopping are essential and distinct elements of appropriate behavioural control with its dysfunction implicated in various impulsivity related mental disorders. Although rodent and human studies have investigated both phenomena, the role of preparing to stop in waiting impulsivity has rarely been investigated. Furthermore, co...

Harmful alcohol use is a major public health issue. In‐person treatment has been hindered by the restrictions necessary during the Covid‐19 pandemic. This study examined the effects of an at‐home smartphone‐based cognitive bias modification training in heavy drinkers. Experiment 1 tested the effect of a short 20–30‐min smartphone‐based approach‐avo...

Background Response inhibition − or the ability to withhold a suboptimal response − relies on the efficacy of fronto-striatal networks, and is impaired in neuropsychiatric disorders including addiction. Cortical paired associative stimulation (cPAS) is a form of transcranial magnetic stimulation (TMS) which can strengthen neuronal connections via s...

Background: Psychiatric comorbidities are common in Parkinson's disease (PD) and may change with high-frequency stimulation targeting the subthalamic nucleus. Numerous accounts indicate subthalamic alpha-frequency oscillation is implicated in emotional processing. While intermittent alpha-frequency (10Hz) stimulation induces positive emotional eff...

Introduction Deep brain stimulation (DBS) studies in Parkinson's Disease (PD) targeting the subthalamic nucleus (STN) have characterized its spectral properties across cognitive processes. In emotional evaluation tasks, specific alpha frequency (8–12 Hz) event-related de-synchronization (ERD) (reduced power) has been demonstrated. The time-locked s...

Introduction Waiting and stopping are essential and distinct elements of appropriate behavioral control with its dysfunction implicated in various impulsivity related mental disorders. Although rodent and human studies have investigated both phenomena, the role of preparing to stop in waiting impulsivity has rarely been investigated. Furthermore, c...

Background: Decision-making is frequently associated with risk-taking under uncertainty. Elevated "intolerance of uncertainty" is suggested to be a critical feature of obsessive-compulsive disorder (OCD). However, impairments of latent constructs of uncertainty processing and its neural correlates remain unclear in OCD. Methods: We scanned 83 pa...

Gambling disorder (GD) is a behavioral addiction associated with personal, social and occupational consequences. Thus, examining GD's clinical relationship with its neural substrates is critical. We compared neural fingerprints using diffusion tensor imaging (DTI) in GD subjects undergoing treatment relative to healthy volunteers (HV). Fifty-three...

Functional neurological disorder (FND) is a common and disabling disorder, often misunderstood by clinicians. Although viewed sceptically by some, FND is a diagnosis that can be made accurately, based on positive clinical signs, with clinical features that have remained stable for over 100 years. Despite some progress in the last decade, people wit...

Ablative procedures such as anterior capsulotomy are potentially effective in refractory obsessive-compulsive disorder (OCD). Converging evidence suggests the ventral internal capsule white matter tracts traversing the rostral cingulate and ventrolateral prefrontal cortex and thalamus is the optimal target for clinical efficacy across multiple deep...

The deep brain stimulation (DBS) Think Tank X was held on August 17–19, 2022 in Orlando FL. The session organizers and moderators were all women with the theme women in neuromodulation . Dr. Helen Mayberg from Mt. Sinai, NY was the keynote speaker. She discussed milestones and her experiences in developing depression DBS. The DBS Think Tank was fou...

Gambling disorder (GD) is major public health issue. The disorder is often characterized by elevated impulsivity with evidence from analogous substance use disorders underlining prominent roles of brain monoamines in addiction susceptibility and outcome. Critically, GD allows the study of addiction mechanisms without the confounder of the effects o...

Background Though deep brain stimulation (DBS) shows increasing potential in treatment-resistant depression (TRD), the underlying neural mechanisms remain unclear. Here, we investigated functional and structural connectivities related to and predictive of clinical effectiveness of DBS at ventral capsule/ventral striatum region for TRD. Methods Sti...

The amygdala, orbitofrontal cortex (OFC) and medial prefrontal cortex (mPFC) form a crucial part of the emotion circuit, yet their emotion induced responses and interactions have been poorly investigated with direct intracranial recordings. Such high-fidelity signals can uncover precise spectral dynamics and frequency differences in valence process...

Neurons in the primate lateral habenula fire in response to punishments and are inhibited by rewards. Through its modulation of midbrain monoaminergic activity, the habenula is believed to play an important role in adaptive behavioural responses to punishment and underlie depressive symptoms and their alleviation with ketamine. However, its role in...

Objectives Converging evidence supports the effectiveness of anterior capsulotomy in the management of selected patients with refractory obsessive-compulsive disorder (OCD). Less is understood about the post-operative neural changes that contribute to clinical improvements or impairments that might occur which potentially could be avoided. The obje...

Objectives/Aims The amygdala, orbitofrontal cortex (OFC) and medial prefrontal cortex (mPFC) form a crucial part of the emotion circuit and their dysfunction is implicated in affective disorders attested by numerous functional magnetic resonance (fMRI) studies. However, the precise nature of emotion induced spectral responses and interactions among...

Background Depressive disorders (DD) are widely recognized as one of the most frequent neuropsychiatric disorders in Parkinson´s disease. Patients with late-stage Parkinson´s disease (LSPD) continue to be a neglected population, and little is known about DD frequency in LSPD. Objectives To determine the frequency of DD in LSPD patients through a c...

Deep brain stimulation is an effective treatment for obsessive–compulsive disorder but is rarely used. Action is needed by psychologists, psychiatrists and insurers so that patients with otherwise intractable cases can receive this therapy to improve their mental health.

Subthalamic nucleus (STN) deep brain stimulation (DBS) can improve motor symptoms in Parkinson’s disease (PD), as well as potentially improving otherwise intractable comorbid depressive symptoms. To address the latter issue, we evaluated the severity of depressive symptoms along with the severity of motor symptoms in 18 PD patients (mean age, 58.4...

Background The subthalamic nucleus (STN) is an effective deep brain stimulation target for Parkinson disease (PD) and obsessive-compulsive disorder and has been implicated in reward and motivational processing. In this study, we assessed the STN and prefrontal oscillatory dynamics in the anticipation and receipt of reward and loss using a task comm...

Background: Depressive disorders are recognized as a common neuropsychiatric disorder of Parkinson's disease (PD). Reported frequencies vary widely among studies and depend on the diagnostic criteria, the methods of ascertainment used, and the population sampled. Objective: We aimed to evaluate the frequency of depressive disorders in PD and to...

Background Alcohol misuse is a major global public health issue. The disorder is characterized by aberrant neural networks interacting with environment and genetics. Dissecting the neural substrates and functional networks that relate to longitudinal changes in alcohol use from those that relate to alcohol misuse cross-sectionally is important to e...

Schizophrenia is a neurodevelopmental disorder manifesting differing impairments at early onset and chronic disease stages. Brain imaging research suggests a core pathological region in patients with first-episode schizophrenia is Broca's area. With disease progression, alterations in thalamic connectivity becomes more prevalent. Understanding the...

The habenula is an epithalamic structure implicated in negative reward mechanisms and plays a downstream modulatory role in regulation of dopaminergic and serotonergic functions. Human and animal studies show its hyperactivity in depression which is curtailed by the antidepressant response of ketamine. Deep brain stimulation of habenula (DBS) for m...

Neurophysiological work in primates and rodents have shown the amygdala plays a central role in reward processing through connectivity with the orbitofrontal cortex (OFC) and hippocampus. However, understanding the role of oscillations in each region and their connectivity in different stages of reward processing in humans has been hampered by limi...

Deep brain stimulation (DBS) of structures in the brain’s reward system is a promising therapeutic option for patients with treatment-resistant depression (TRD). Recently, DBS of the habenula (HB) in the brain’s anti-reward system has also been reported to alleviate depressive symptoms in patients with TRD or bipolar disorder (BD). In this pilot op...

Neurosurgical interventions including deep brain stimulation (DBS) and capsulotomy have been demonstrated effective for refractory obsessive-compulsive disorder (OCD), although treatment-shared/-specific network mechanisms remain largely unclear. We retrospectively analyzed resting-state fMRI data from three cohorts: a cross-sectional dataset of 18...

Objective: Abnormal selective attention to drug cues and negative affect is observed in patients with substance dependence, and it is closely associated with drug addiction and relapse. Methadone maintenance is an effective replacement therapy to treat heroin addiction, which significantly reduces the relapse rate. The present study examines whethe...

Suicide is a major but possibly preventable public health issue. Suicidal ideation is common in Parkinson’s disease. Although completed suicides were once suggested to occur much less frequently than expected, multiple large-scale studies suggest an elevated risk relative to the general population, although country-specific or cultural factors may...

Background: Psychotic symptoms are highly frequent in Parkinson's disease (PD) patients and are associated with poor prognosis. They include hallucinations, delusions, and minor psychotic phenomena, including sense of presence, passage hallucinations, and illusions. Objective: To evaluate the frequency of psychosis in PD patients. Methods: A s...

Background There is rare reports about opinions and clinical practice of functional movement disorders (FMD) in China. The present survey aimed to investigate the views of FMD in Chinese clinicians. Methods The Chinese version survey of FMD were conducted in nationwide practitioners by means of an online questionnaire. Results Four hundred and th...

Background Psychosis is a frequent non-motor symptom in Parkinson’s disease (PD). Estimates of the frequency of Parkinsońs disease psychosis (PDP) vary widely. Knowledge about the frequency and phenomenology of psychosis in late-stage (LS) PD patients is limited. This study aimed to determine the frequency of psychosis in LSPD patients through clin...

A third of patients receiving Interferon-α (IFN-α) treatment for Hepatitis-C develop major depressive disorder (MDD). Conversely, anti-Tumor Necrosis Factor (TNF) therapies improve depression providing key empirical support for the “inflammatory theory” of depression. Heightened amygdala reactivity (particularly to negatively valanced stimuli) is a...

Cannabis use has historically been thought to cause amotivation, but the relationship between cannabis and apathy, anhedonia, and reward processing remains poorly characterised. In this systematic review, we evaluated whether cannabis exposure acutely and/or non-acutely was associated with altered reward processing using questionnaire, behavioural,...

Objectives Impulsivity is a multifaceted construct that involves a tendency to act prematurely with little foresight, reflection or control. Waiting impulsivity is one aspect of action impulsivity and is commonly studied in animals using tasks such as the 5-choice serial reaction time task (5CSRTT). ¹ It is neurochemically distinct from motor respo...

Introduction Evaluation of the available choices, an integral step in decision-making, leads to the selection of the optimal and most rewarding one. This process of choice selection depends on its features such as value and reward-likelihood, which form the basis for constructs such as Conflict - easy or difficult (difference between reward probabi...

Objectives/Aims To examine the temporal and spectral characteristics of local field potentials recorded from the amygdala in epilepsy in the context of the anticipation and receipt of rewards and losses using an incentive learning task and a risky decision-making task. Methods 16 Epilepsy patients completed two tasks. In the monetary incentive del...

Objectives and Aims The Coronavirus (COVID-19) pandemic has required drastic safety measures to contain virus spread, including an extended self-isolation period. Those with greater perceived or actual life stress are vulnerable to develop or reinstate problematic behaviours characterised by addiction and compulsive mechanisms. Thus, we assessed ho...

Obsessive-compulsive disorder is among the most disabling psychiatric disorders. Although deep brain stimulation is considered an effective treatment, its use in clinical practice is not fully established. This is, at least in part, due to ambiguity about the best suited target and insufficient knowledge about underlying mechanisms. Recent advances...

Background and aim The Coronavirus (COVID-19) pandemic has required drastic safety precautions to contain virus spread, involving a protracted self-isolation period. Those with greater perceived or actual life stress are vulnerable to develop problematic internet behaviors. Thus, we assessed how COVID-19 social isolation affected online gaming (OG)...

Conversion disorder, also called Functional Neurological Symptom Disorder is poorly understood by many in the medical profession and is associated with considerable health care costs. Sigmund Freud, in an early, pre-psychoanalytic period paper, suggested that hysterical motor paralyses arose from a “functional or dynamic lesion” which was no differ...

A number of convergent human neuroimaging and animal studies suggest that habenula neurons fire in anticipation of non-rewarding outcomes, and suppress their firing in anticipation of rewarding outcomes. This normative function of the habenula appears disrupted in depression, and may be critical to the anti-depressant effects of ketamine. However,...

Background Disorders of substance and behavioral addiction are believed to be associated with a myopic bias towards the incentive salience of addiction-related cues away from general rewards in the environment. In non-treatment seeking gambling disorder patients, neural activity to anticipation of monetary rewards is enhanced relative to erotic rew...

Background Risk is an essential trait of most daily decisions. Our behaviour when faced with risks involves evaluation of many factors including the outcome probabilities, the valence (gains or losses) and past experiences. Several psychiatric disorders belonging to distinct diagnostic categories, including pathological gambling and addiction, show...

Background Methadone maintenance treatment (MMT) is effective in decreasing opioid use or facilitating abstinence. Previous studies using small opioid use disorder samples suggest that cognitive impairments including impulsivity and executive functions may partially improve on MMT, but a range of deficits may persist. However, systematic assessment...

The GABAB receptor (GABABR) agonist baclofen has been used to treat alcohol and several other substance use disorders (AUD/SUD), yet its underlying neural mechanism remains unclear. The present study aimed to investigate cortical GABABR dynamics following chronic alcohol exposure. Ex vivo brain slice recordings from mice chronically exposed to alco...

Objectives Surgical procedures targeting the anterior limb of the internal capsule (aLIC) can be effective in patients with selected treatment-refractory obsessive-compulsive disorder (OCD). The aLIC consists of white-matter tracts connecting cortical and subcortical structures and show a topographical organisation. Here we assess how aLIC streamli...

Risk evaluation is a critical component of decision making. Risk tolerance is relevant in both daily decisions and pathological disorders such as attention-deficit hyperactivity disorder (ADHD), where impulsivity is a cardinal symptom. Methylphenidate, a commonly prescribed drug in ADHD, improves attention but has mixed reports on risk-based decisi...

Doubt can modulate our decision-making process. Although conceptually different, conflict (choice similarity: difficult or easy) and uncertainty (individual reward-likelihoods: uncertain or certain) are commonly related and often conflated. By posing as an evidence-accumulation problem, we assessed doubt, dissociating contextual conflict, and uncer...

Abstract Tourette syndrome (TS) is a childhood-onset neuropsychiatric disorder characterized by the presence of multiple motor and vocal tics. TS usually co-occurs with one or multiple psychiatric disorders. Although behavioral and pharmacological treatments for TS are available, some patients do not respond to the available treatments. For these p...

OBJECTIVE The ongoing coronavirus disease 2019 (COVID-19) pandemic has considerably affected the delivery of postoperative care to patients who have undergone deep brain stimulation (DBS) surgery. DBS teleprogramming technology was developed and deployed in China before the COVID-19 outbreak. In this report, the authors share their experiences with...

Background Emotional processing is a core cognitive process cutting across neuropsychiatric disorders. Understanding the neurophysiological features underlying depressive symptoms and their sensitivity to modulation is critical to modifying emotional bias. The subthalamic nucleus (STN), targeted in Parkinson’s disease (PD) shows a late alpha-desync...

Intentional inhibition, the endogenous decision to stop or cancel an action, is arguably a more ecologically valid process than automatized, reactive, inhibition which occurs in response to an external stop signal without active decision making at the moment of inhibition. Choosing to stop an act of opening the fridge door, or of reaching for a bot...

Background: The prediction of alcohol consumption in youths and particularly biomarkers of resilience, is critical for early intervention to reduce the risk of subsequent harmful alcohol use. Methods: At baseline, the longitudinal relaxation rate (R1), indexing grey matter myelination (i.e. myeloarchitecture), was assessed in 86 adolescents/young a...

Schizophrenic patients often do not have the sense that they direct their own movements or author their own thoughts (passivity phenomena). As willing must precede movement to be causal and thus generate the sense of agency, it is possible that the timing between the senses of willing and movement is shortened in schizophrenia. We tested the subjec...

Background: The Obsessive Compulsive Drug Use Scale (OCDUS) measures the overall craving level within a period from a multidimensional perspective. However, no studies have addressed the validity of the new OCDUS factor structure, presented in 2016, in China. Additionally, there is lack of evidence on the interaction among risk factors for relapse...

The American Neuropsychiatric Association's Committee on Research assigned the task of defining the most helpful clinical factors and tests in establishing the diagnosis of psychogenic nonepileptic seizures (PNES) during a neuropsychiatric assessment. A systematic review of the literature was conducted using three search engines and specified searc...

Functional neurological (conversion) disorder (FND) is a prevalent and disabling condition at the intersection of neurology and psychiatry. Advances have been made in elucidating an emerging pathophysiology for motor FND, as well as in identifying evidenced-based physiotherapy and psychotherapy treatments. Despite these gains, important elements of...

Objectives/Aims The habenular nucleus is a set of well-conserved structures involved in aversive reward and is inhibitory to major monoaminergic nuclei. Several cases indicated that it is a promising deep brain stimulation (DBS) target for treatment of major depressive disorder (MDD). In this study, we assess the effectiveness and safeness of bilat...

Objectives/Aims To examine the causal role of the subthalamic nucleus (STN) in externally cued or internally generated decisions to execute or withhold an action by recording and stimulating neural activity in this region using deep brain stimulation (DBS) electrodes implanted for the treatment of Parkinson’s disease (PD). Methods 20 PD patients c...

Objectives/Aims Surgical procedures targeting the anterior limb of the internal capsule (aLIC) can be effective in medically refractory obsessive-compulsive disorder (OCD). The aLIC consists of white-matter tracts connecting cortical and subcortical structures. Here we assess how specific aLIC tracts are affected in OCD and which tracts predicts im...

Introduction Social anxiety disorder or phobia (SAD) is a debilitating condition, where an individual experiences overwhelming fear to situations involving social interactions. Prototypically, SAD presents as shy, submissive, inhibited, and risk- aversive behaviours. Contrastingly, an atypical sub-group show impulsive, aggressive, novelty-seeking b...

Introduction: To evaluate the current utilization and challenges in fully implementing the use of deep brain stimulation (DBS) treatment in Asia and Oceania. Methods: We conducted a medical literature search to identify DBS research performed by investigators with a primary affiliation in Asian and Oceania countries between March 1, 2013, and March...

Background: Several neuroablative procedures are available for severe and treatment-resistant obsessive-compulsive disorder (OCD), but limited knowledge about their relative clinical advantages and disadvantages poses obstacles for treatment decision-making. Methods: We searched PubMed, Embase, Scopus, Web of Knowledge and the Cochrane Library f...

Insight into motivational processes may be gained by examining measures of willingness to exert effort for rewards, which have been linked to neuropsychiatric symptoms of anhedonia and apathy. However, while much work has focused on the development of models of motivation based on classic tasks of externally-generated levels of effort for reward, t...

Natural rewards such as erotic stimuli activate common neural pathways with monetary rewards. In human studies, the manipulation of dopamine and serotonin play an important role in the processing of monetary rewards with less understood on its role on erotic stimuli. In this study, we investigate the neuromodulatory effects of dopaminergic and sero...

Background Anterior capsulotomy that surgically targets fiber tracts connecting prefrontal cortex and subcortical nuclei is a therapeutic option for a subgroup of treatment refractory obsessive-compulsive disorder (OCD) patients. To investigate neural correlates and predictors of clinical improvement to anterior capsulotomy. Methods Structural and...

Alcohol misuse and addiction are major international public health issues. Addiction can be characterized as a disorder of aberrant neurocircuitry interacting with environmental, genetic and social factors. Neuroimaging in alcohol misuse can thus provide a critical window into underlying neural mechanisms, highlighting possible treatment targets an...

Objective The present study aimed to assess the psychometric properties of a Chinese version of the UPPS-P Impulsive Behavior Scale. The associations between the UPPS-P scale and impulsivity choice, gender, smoking, and drinking status were also assessed. Methods A total of 127 adults ranging from 21 to 65 years old participated in the study. Part...

Objectives Transcranial magnetic stimulation (TMS) holds potential promise as a therapeutic modality for disorders of addiction. Our previous findings indicate that high-frequency repetitive transcranial magnetic stimulation (rTMS) over the left dorsal–lateral prefrontal cortex (DLPFC) and low-frequency rTMS over the right DLPFC can reduce drug cra...

Our daily decisions are governed by the arbitration between goal-directed and habitual strategies. However, the neurochemical basis of this arbitration is unclear. We assessed the contribution of dopaminergic, serotonergic, and opioidergic systems to this balance across reward and loss domains. Thirty-nine participants (17 healthy controls, 15 pati...

Background Some patients suffer from persistent and severely disabling Obsessive-Compulsive Disorder (OCD) symptoms that cannot be alleviated by conventional treatments or neuroablative interventions targeting cortico-striatal loop circuits. Currently, it is unclear how to manage the clinical symptoms of these unique patients. We reasoned that deep...

Objectives Late-life depression (LLD) has negative impacts on somatic, emotional and cognitive domains of the lives of patients. Elucidating the abnormality in the brain networks of LLD patients could help to strengthen the understanding of LLD pathophysiology, however, the studies exploring the spontaneous brain activity in LLD during the resting...

In an attempt to improve attention bias modification (ABM), we tested whether an attentional training protocol which featured monetary operant conditioning of eye-gaze to avoid alcohol stimuli in alcohol-dependent patients could reduce attention, craving and relapse to alcohol. We employed a pilot randomized control trial (RCT) with 21 detoxified a...

Background: The mesial prefrontal cortex, cingulate cortex, and the ventral striatum are key nodes of the human mesial fronto-striatal circuit involved in decision-making and executive function and pathological disorders. Here we ask whether deep wide-field repetitive transcranial magnetic stimulation (rTMS) targeting the mesial prefrontal cortex (...