Basal ganglia

…ventricles, hippocampus, fornix, basal ganglia and thalamus, with further exploration of the brainstem and cerebellum. Traditional blunt dissection reveals major pathways, while axial, sagittal and coronal MRI comparisons connect anatomy to imaging. Consolidation and self-assessment sessions help participants test their recognition of structures. Live online via Zoom

Investigate basal ganglia mechanisms of learning and adaptive behaviour in Jeff Wickens’s Neurobiology Research Unit, focusing on dopamine and acetylcholine dynamics in the rodent striatum. The work combines two-photon imaging, fibre photometry and behavioural tasks in virtual reality or operant boxes, with analysis and manuscript preparation. This full-time appointment initially lasts two years, starting as soon as possible after 1 January 2027. Expected annual salary is JPY 4.6–5.9 million. Applications remain open until all positions are filled. Follow the official page’s email instructions

Basal ganglia are essential for learning and adapting movements, yet their output is often unnecessary for executing learned actions. A biologically grounded model of the closed cortico-basal ganglia-thalamocortical loop explains this apparent discrepancy. Dopamine-dependent plasticity, recurrent cortical dynamics and basal ganglia feedback jointly support early motor acquisition and adaptation, shaping cortical activity even when basal ganglia output is no longer directly required. Parallel loops form functional channels for particular motor outputs. Neural recordings during zebra finch song

…are the contributions of the cortex, basal ganglia, and thalamus to behavior? In addressing these questions, we often ascribe function to each area as if it were an independent processing unit. However, we know from the anatomy that the cortex, basal ganglia, and thalamus, are ma

…One of these systems, the basal ganglia, instantiates a reinforcement learning (RL) algorithm in which dopamine (DA) neurons transmit reward prediction error (RPE) signals---the difference between actual and expected rewards---to enable value learning via cortico-striatal plasticity. Recent studies have highlighted two novel aspects: first, that RPE signals from midbrain DA neurons can encode entire reward distributions through a distributional RL algorithm that mirrors cutting-edge machine

…subcortical regions within basal ganglia (BG). In investigating the specific function of each region in this process, the role of BG remains a matter of vigorous debate. While many studies have shown decision-related activity in BG nuclei, this activity appears significantly later than in associated cortical regions, and may not be the primary driver of decisions. Also, while BG stimulation can bias choices, in

The ability to flexibly time movements is crucial for behavior. The motor cortex, basal ganglia, and thalamus form a multiregional neural network, known as the cortico-basal ganglia thalamocortical (CBGTC) loop, which controls various aspects of motor behaviors, including the timing of actions [1]. For example, in mice performing a delayed licking task, average activity in the striatum and cortex ramp up to a threshold for executing a lick [2]. However, the distinct contributions from different cell types and regions within the CBGTC loop remain largely unknown due to the similarity in their r

…distinguishes between the roles of the basal ganglia and cerebellum, addressing limitations of current models in complex motor control tasks. We introduce a decomposition of the value function where the RL component optimizes the mean expected value while the cerebellar module minimizes deviations from optimal latent trajectories. This decomposition approximates a normative information-theoretic objective where the

The simple decision to seek and consume food requires integrating slowly changing information about internal state with rapid sensory processes indicating food availability. Whether fast and slow components unite in a single integrating location [2] or whether they are also integrated in a more distributed fashion remains unknown. Can neural population dynamics simultaneously encode multiple timescales? Could modeling such temporal multiplexing help us understand how the brain integrates temporal information to guide appetitive behavior? To examine these questions, we recorded neural populati

The basal ganglia are a network of subcortical nuclei that play a central role in regulating motor and cognitive functions. A critical hub in these structures is the external globus pallidus (GPe) as it links all nuclei in this network. This nucleus was long considered a homogenous relay in the motor-suppressing indirect pathway. However, the GPe is anatomically and functionally diverse. How the GPe subpopulations contribute differentially to cognitive and motor function is currently unknown. Here, we find (1) that the GPe encodes motor and value signals in distinct subpopulations, (2) that th

A major organizing principle of the brain proposes that the cortex, basal ganglia, and thalamus are interconnected in parallel recurrent loops. According to this model, the two principal basal ganglia pathways – termed direct and indirect – are thought to excite and inhibit cortical activity via their outputs to thalamus. Here, we test this model by simultaneously recording activity across cortex and striatum, while inhibiting the direct or indirect basal ganglia pathway as mice perform an evidence-accumulation task in which each manipulation produces opposing decision biases. Inconsistent wit

…dopamine (DA) projections within the basal ganglia (BG) drive RBL via reinforcement learning, while the cerebellum (CB) supports EBL via supervised learning. In doing so, we introduce a novel learning framework that combines DA-driven RBL with CB-driven EBL. Specifically, we reformulate the traditional RBL and EBL synaptic weight updates in terms of a shared ‘action-gradient’ spac

…a neuro-computational model of the basal ganglia to investigate how DBS influences decision-making by enhancing cortico-thalamic shortcuts and altering basal ganglia plasticity, particularly in the context of a probabilistic reversal-learning task. We adjusted our basal ganglia model parameters to replicate patient behavior data from Marcelino et al. (2023). Simulations

…The basal ganglia have been implicated, and a transition from dorsomedial striatum (DMS), mediating variable behavior, to dorsolateral st

The external Globus Pallidus (GPe) is a central hub in the basal ganglia. This structure is composed mainly of GABAergic neurons, which are divided into two distinct subtypes called: prototypic (70%) and arkypallidal (ARKY: 20%) neurons differentiated by their molecular and electrophysiological signatures. ARKY neurons project exclusively to the striatum and send a stop signal that interrupt ongoing action, suggesting their key role in movement control. However, little is known about the contribution of ARKY neurons to the pathophysiology of Parkinson’s Disease (PD). Moreover, it has been rece

The neuronal population of the striatum is primarily composed of medium spiny projecting neurons (MSNs), with only a small percentage (around 5% in mice) being locally projecting neurons or interneurons. Despite their low numbers, interneurons play a crucial role in regulating the flow of information within the striatum and to other brain nuclei, thereby having significant implications for motor control and cognition.We recently identified one of the most abundant populations of GABAergic interneurons in the striatum that express Pthlh and varying levels of Pvalb, which correlates with intrins

Basal ganglia (BG) circuits are crucial for motor initiation and suppression. Dopamine loss in these circuits triggers Parkinson's disease (PD) and debilitating motor impairments such as akinesia and bradykinesia. Levodopa treatments alleviates PD symptoms, but often leads to abnormal involuntary movements known as levodopa-induced dyskinesias (LIDs). Understanding the neuronal mechanism of LIDs is essential for developing novel therapeutic strategies. Recent studies suggest that LIDs result from abnormal striatal activity, yet how this activity affects downstream BG circuits to generate LIDs

…control is governed by the cortico-basal ganglia- thalamocortical loops, with recent investigations highlighting the pivotal role of basal ganglia downstream projections to pedunculopontine nucleus (PPN) in regulating specific motor programs. Despite these advancements, the precise mechanisms through which the basal ganglia networks selectively control these functional motor modules remain incompletely elucidated. Our findings in mouse reveal that th

…in the primary motor cortex (M1) and basal ganglia (BG). Dopamine (DA) mediates these changes, with Darpp-32 playing a key role in DA transmission. Although extensively studied in the BG's striatum, Darpp-32's function in the motor cortex remains largely unexplored. This study aims to characterize Darpp-32 in motor cortices, examining cellular expression and its impact on motor behavior, synaptic and structural plasticity.Methods: Anatomical study: Using C57BL/6 mice, we examined Darpp-32 distribution across corti

Understanding the basal ganglia's role in initiating and executing action sequences is crucial for treating Parkinson's disease (PD). Recent experimental data challenge the classical model attributing pro- and anti-kinetic functions to direct and indirect pathways of the basal ganglia. To better understand movement-related neuronal activity in the basal ganglia, we performed large-scale electrophysiological recordings with Neuropixels probes in awake, behaving mice in the dorsomedial and dorsolateral striatum (DMS and DLS, respectively). We used the MitoPark mouse, a genetic model of PD, to in

Basal ganglia (BG) are believed to involve in motor planning and control. Its striatum receives cortical, thalamic, and substantia nigra inputs and shows uneven distribution of μ-opioid receptor (MOR)-rich striosome and poor matrix. Medium spiny striatal neurons (MSN), distinguished into direct and indirect pathway, are present in both the striosome and matrix. Striatum also contains cholinergic and parvalbumin (PV) interneurons. Despite the complexity, BG are usually discussed with its direct and indirect pathways and overlooking the striosome and matrix compartmentation. Here we studied the

…the cognitive circuitry of the basal ganglia, which receives inputs from frontal cortical areas. Here, we investigated the role of the orbitofrontal cortex (OFC) and its thalamic inputs in behavioral flexibility. This study combined behavioral approaches and in vivo electrophysiology in anesthetized rats. First, we assessed flexibility with a set-shifting task. This procedure alternates between visual discrimination rules and response discrimination rules. An individu

The entopeduncular nucleus EP, one of the basal ganglia(BGs), is considered one of the essential output nuclei, sending synapses belonging to the pathways essential for normal motor activity to two specific regions in the ventral lateral thalamic nuclei(VL) and ventral anterior thalamic nuclei(VA).The basal ganglia innervate the thalamus through 3 pathways:direct, indirect, and hyper-direct.By these three pathways, we get an innervation that causes disinhibition or inhibition of the thalamus.The research aimed to study the thalamus, the relay center for transmitting information received from m

The subthalamic nucleus (STN) holds a strategic position in the basal ganglia circuit, controlling both motor and non-motor functions. Alterations in its neuronal activity have been shown to be involved in the pathophysiology of Parkinson’s disease (PD). In addition to its classical intra-basal ganglia connections, STN neurons also project to several cortical areas. However, the degree of involvement of these subthalamo-cortical projections in motor and non-motor functions, and in the pathophysiology of PD has never been characterized.The aim of this study was to investigate the effects of inh