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1.
Nat Commun ; 10(1): 4798, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641118

RESUMO

Inhibitory control is fundamental to children's self-regulation and cognitive development. Here we investigate cortical-basal ganglia pathways underlying inhibitory control in children and their adult-like maturity. We first conduct a comprehensive meta-analysis of extant neurodevelopmental studies of inhibitory control and highlight important gaps in the literature. Second, we examine cortical-basal ganglia activation during inhibitory control in children ages 9-12 and demonstrate the formation of an adult-like inhibitory control network by late childhood. Third, we develop a neural maturation index (NMI), which assesses the similarity of brain activation patterns between children and adults, and demonstrate that higher NMI in children predicts better inhibitory control. Fourth, we show that activity in the subthalamic nucleus and its effective connectivity with the right anterior insula predicts children's inhibitory control. Fifth, we replicate our findings across multiple cohorts. Our findings provide insights into cortical-basal ganglia circuits and global brain organization underlying the development of inhibitory control.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Adolescente , Adulto , Gânglios da Base/fisiologia , Córtex Cerebral/fisiologia , Criança , Bases de Dados Factuais , Humanos , Imagem por Ressonância Magnética , Tempo de Reação/fisiologia , Núcleo Subtalâmico/fisiologia , Adulto Jovem
2.
Elife ; 82019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31490123

RESUMO

Cortico-basal ganglia-thalamocortical loops are largely conceived as parallel circuits that process limbic, associative, and sensorimotor information separately. Whether and how these functionally distinct loops interact remains unclear. Combining genetic and viral approaches, we systemically mapped the limbic and motor cortico-basal ganglia-thalamocortical loops in rodents. Despite largely closed loops within each functional domain, we discovered a unidirectional influence of the limbic over the motor loop via ventral striatum-substantia nigra (SNr)-motor thalamus circuitry. Slice electrophysiology verifies that the projection from ventral striatum functionally inhibits nigro-thalamic SNr neurons. In vivo optogenetic stimulation of ventral or dorsolateral striatum to SNr pathway modulates activity in medial prefrontal cortex (mPFC) and motor cortex (M1), respectively. However, whereas the dorsolateral striatum-SNr pathway exerts little impact on mPFC, activation of the ventral striatum-SNr pathway effectively alters M1 activity. These results demonstrate an open cortico-basal ganglia loop whereby limbic information could modulate motor output through ventral striatum control of M1.


Assuntos
Gânglios da Base/fisiologia , Sistema Límbico/fisiologia , Córtex Motor/fisiologia , Vias Neurais/fisiologia , Substância Negra/fisiologia , Animais , Gânglios da Base/anatomia & histologia , Fenômenos Eletrofisiológicos , Sistema Límbico/anatomia & histologia , Camundongos , Córtex Motor/anatomia & histologia , Vias Neurais/anatomia & histologia , Ratos , Substância Negra/anatomia & histologia
3.
Brain Struct Funct ; 224(8): 2899-2905, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31446466

RESUMO

Hand preference is a striking example of functional lateralization, with 90% of the population preferentially using their right hand. However, the search for brain structural correlates of this lateralization has produced inconsistent results. While large-scale neuroimaging studies using automated methods have largely failed to find local anatomical asymmetries associated with hand preference, other studies identifying specific motor regions have been able to find local morphological and functional differences. The present study looked at brain asymmetries in the brain's motor system using established cortical landmarks to identify the somatomotor hand region and extracted regional volumes of subcortical and cerebellar regions. Our results showed a strong left-right asymmetry in the cortical hand region, with weaker asymmetries appearing in the striatum and cerebellar white matter. Such asymmetries were much more pronounced in right-handers, whereas much weaker or absent lateralizing effects were observed in left-handed subjects. This study demonstrates the importance of local landmarks in studying individual anatomical differences. More generally, establishing structural correlates of hand preference is important, as this could further establish the origins of cerebral lateralization.


Assuntos
Gânglios da Base/anatomia & histologia , Cerebelo/anatomia & histologia , Córtex Cerebral/anatomia & histologia , Lateralidade Funcional , Substância Branca/anatomia & histologia , Adulto , Gânglios da Base/fisiologia , Mapeamento Encefálico , Cerebelo/fisiologia , Córtex Cerebral/fisiologia , Feminino , Mãos , Humanos , Imagem por Ressonância Magnética , Masculino , Substância Branca/fisiologia , Adulto Jovem
4.
Brain Lang ; 197: 104665, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31470347

RESUMO

Bilingual language control is characterized by the ability to select from amongst competing representations based on the current language in use. According to the Conditional Routing Model (CRM), this feat is underpinned by basal-ganglia signal-routing mechanisms, and may have implications for cognitive flexibility. The current experiment used dynamic causal modeling of fMRI data to compare network-level brain functioning in monolinguals and bilinguals during a task that required productive (semantic decision) and receptive (language) switches. Consistent with the CRM, results showed that: (1) both switch types drove activation in the basal ganglia, (2) bilinguals and monolinguals differed in the strength of influence of dorsolateral prefrontal cortex (DLPFC) on basal ganglia, and (3) differences in bilingual language experience were marginally related to the strength of influence of the switching drives onto basal ganglia. Additionally, a task-by-group interaction was found, suggesting that when bilinguals engaged in language-switching, their task-switching costs were reduced.


Assuntos
Gânglios da Base/fisiologia , Modelos Neurológicos , Multilinguismo , Mapeamento Encefálico , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/fisiologia , Adulto Jovem
5.
Physiol Int ; 106(2): 95-113, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271309

RESUMO

The purpose of this paper is to give an overview of our present knowledge about the feline tecto-thalamo-basal ganglia cortical sensory pathway. We reviewed morphological and electrophysiological studies of the cortical areas, located in ventral bank of the anterior ectosylvian sulcus as well as the region of the insular cortex, the suprageniculate nucleus of the thalamus, caudate nucleus, and the substantia nigra. Microelectrode studies revealed common receptive field properties in all these structures. The receptive fields were extremely large and multisensory, with pronounced sensitivity to motion of visual stimuli. They often demonstrated directional and velocity selectivity. Preference for small visual stimuli was also a frequent finding. However, orientation sensitivity was absent. It became obvious that the structures of the investigated sensory loop exhibit a unique kind of information processing, not found anywhere else in the feline visual system.


Assuntos
Gânglios da Base/fisiologia , Encéfalo/fisiologia , Vias Visuais/fisiologia , Vias Aferentes/fisiologia , Animais , Gatos , Neurônios/fisiologia , Estimulação Luminosa/métodos
6.
Int Rev Neurobiol ; 146: 229-257, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31349929

RESUMO

The basal ganglia (BG), an organized network of nuclei that integrates cortical information, play a crucial role in controlling motor function. In fact, movement disorders such as Parkinson's disease (PD) and Huntington's disease (HD) are caused by the degeneration of specific structures within the BG. There is substantial evidence supporting the idea that cannabinoids may constitute novel promising compounds for the treatment of movement disorders as neuroprotective and anti-inflammatory agents. This potential therapeutic role of cannabinoids is based, among other qualities, on their capacity to reduce oxidative injury and excitotoxicity, control calcium influx and limit the toxicity of reactive microglia. The mechanisms involved in these effects are related to CB1 and CB2 receptor activation, although some of the effects are CB receptor independent. Thus, taking into account the aforementioned properties, compounds that act on the endocannabinoid system could be useful as a basis for developing disease-modifying therapies for PD and HD.


Assuntos
Canabinoides/uso terapêutico , Endocanabinoides/fisiologia , Doença de Huntington/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Animais , Gânglios da Base/patologia , Gânglios da Base/fisiologia , Canabinoides/farmacologia , Endocanabinoides/uso terapêutico , Humanos , Doença de Huntington/patologia , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/patologia
7.
Neuron ; 103(3): 445-458.e10, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31202541

RESUMO

To make adaptive decisions, organisms must appropriately filter sensory inputs, augmenting relevant signals and suppressing noise. The prefrontal cortex (PFC) partly implements this process by regulating thalamic activity through modality-specific thalamic reticular nucleus (TRN) subnetworks. However, because the PFC does not directly project to sensory TRN subnetworks, the circuitry underlying this process had been unknown. Here, using anatomical tracing, functional manipulations, and optical identification of PFC projection neurons, we find that the PFC regulates sensory thalamic activity through a basal ganglia (BG) pathway. Engagement of this PFC-BG-thalamus pathway enables selection between vision and audition by primarily suppressing the distracting modality. This pathway also enhances sensory discrimination and is used for goal-directed background noise suppression. Overall, our results identify a new pathway for attentional filtering and reveal its multiple roles in sensory processing on the basis of internal goals.


Assuntos
Gânglios da Base/fisiologia , Vias Neurais/fisiologia , Córtex Pré-Frontal/fisiologia , Filtro Sensorial/fisiologia , Tálamo/fisiologia , Estimulação Acústica , Animais , Condicionamento Operante , Sinais (Psicologia) , Dependovirus/genética , Aprendizagem por Discriminação/fisiologia , Eletrodos Implantados , Vetores Genéticos , Camundongos , Ruído , Optogenética , Estimulação Luminosa , Recompensa , Detecção de Sinal Psicológico/fisiologia
8.
Elife ; 82019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31099755

RESUMO

Complex motor skills take considerable time and practice to learn. Without continued practice the level of skill performance quickly degrades, posing a problem for the timely utilization of skilled motor behaviors. Here we quantified the recurring development of vocal motor skills and the accompanying changes in synaptic connectivity in the brain of a songbird, while manipulating skill performance by consecutively administrating and withdrawing testosterone. We demonstrate that a songbird with prior singing experience can significantly accelerate the re-acquisition of vocal performance. We further demonstrate that an increase in vocal performance is accompanied by a pronounced synaptic pruning in the forebrain vocal motor area HVC, a reduction that is not reversed when birds stop singing. These results provide evidence that lasting synaptic changes in the motor circuitry are associated with the savings of motor skills, enabling a rapid recovery of motor performance under environmental time constraints.


Assuntos
Músculos Laríngeos/fisiologia , Destreza Motora/fisiologia , Aves Canoras/fisiologia , Vocalização Animal/fisiologia , Animais , Gânglios da Base/fisiologia , Aprendizagem/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia , Prosencéfalo/fisiologia , Testosterona/metabolismo
9.
Can J Exp Psychol ; 73(2): 118-134, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31021110

RESUMO

The prevalence of bilingualism has prompted considerable interest in the effects of speaking 2 languages on the mind and brain, and although it is now well-established that both languages are simultaneously active in the bilingual mind, whether this has any effect on general cognition remains a matter of intense debate. In this review, we examine some of the theoretical underpinnings and hypotheses of bilingual benefits, as well as experimental evidence in favor of and against the bilingual advantage claim. Given the complicated results of behavioral studies, we support a more holistic, brain-based approach to exploring the effects of bilingualism on cognitive control, and review 2 recent theories that outline neurobiological mechanisms by which the ability to control 2 languages affects general cognitive processes. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Gânglios da Base/fisiologia , Multilinguismo , Rede Nervosa/fisiologia , Córtex Pré-Frontal/fisiologia , Função Executiva , Humanos
10.
PLoS One ; 14(4): e0214926, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30978216

RESUMO

Motor adaptation to perturbations is provided by learning mechanisms operating in the cerebellum and basal ganglia. The cerebellum normally performs motor adaptation through supervised learning using information about movement error provided by visual feedback. However, if visual feedback is critically distorted, the system may disengage cerebellar error-based learning and switch to reinforcement learning mechanisms mediated by basal ganglia. Yet, the exact conditions and mechanisms of cerebellum and basal ganglia involvement in motor adaptation remain unknown. We use mathematical modeling to simulate control of planar reaching movements that relies on both error-based and non-error-based learning mechanisms. We show that for learning to be efficient only one of these mechanisms should be active at a time. We suggest that switching between the mechanisms is provided by a special circuit that effectively suppresses the learning process in one structure and enables it in the other. To do so, this circuit modulates learning rate in the cerebellum and dopamine release in basal ganglia depending on error-based learning efficiency. We use the model to explain and interpret experimental data on error- and non-error-based motor adaptation under different conditions.


Assuntos
Adaptação Fisiológica/fisiologia , Gânglios da Base/fisiologia , Cerebelo/fisiologia , Modelos Neurológicos , Movimento/fisiologia , Humanos
11.
J Clin Neurosci ; 63: 1-7, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30827880

RESUMO

Of all the truncothalamic nuclei, the centromedian-parafascicular nuclei complex (CM-Pf) is the largest and is considered the prototypic thalamic projection system. Located among the caudal intralaminar thalamic nuclei, the CM-Pf been described by Jones as "the forgotten components of the great loop of connections joining the cerebral cortex via the basal ganglia". The CM, located lateral relative to the Pf, is a major source of direct input to the striatum and also has connections to other, distinct region of the basal ganglia as well as the brainstem and cortex. Functionally, the CM participates in sensorimotor coordination, cognition (e.g. attention, arousal), and pain processing. The role of CM as 'gate control' function by propagating only salient stimuli during attention-demanding tasks has been proposed. Given its rich connectivity and diverse physiologic role, recent studies have explored the CM as potential target for neuromodulation therapy for Tourette syndrome, Parkinson's disease, generalized epilepsy, intractable neuropathic pain, and in restoring consciousness. This comprehensive review summarizes the structural and functional anatomy of the CM and its physiologic role with a focus on clinical implications.


Assuntos
Núcleos Intralaminares do Tálamo/fisiologia , Transtornos dos Movimentos/fisiopatologia , Gânglios da Base/fisiologia , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Córtex Cerebral/fisiopatologia , Humanos , Núcleos Intralaminares do Tálamo/anatomia & histologia , Núcleos Intralaminares do Tálamo/fisiopatologia , Doença de Parkinson/fisiopatologia
12.
PLoS Comput Biol ; 15(2): e1006285, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30818357

RESUMO

A set of sub-cortical nuclei called basal ganglia is critical for learning the values of actions. The basal ganglia include two pathways, which have been associated with approach and avoid behavior respectively and are differentially modulated by dopamine projections from the midbrain. Inspired by the influential opponent actor learning model, we demonstrate that, under certain circumstances, these pathways may represent learned estimates of the positive and negative consequences (payoffs and costs) of individual actions. In the model, the level of dopamine activity encodes the motivational state and controls to what extent payoffs and costs enter the overall evaluation of actions. We show that a set of previously proposed plasticity rules is suitable to extract payoffs and costs from a prediction error signal if they occur at different moments in time. For those plasticity rules, successful learning requires differential effects of positive and negative outcome prediction errors on the two pathways and a weak decay of synaptic weights over trials. We also confirm through simulations that the model reproduces drug-induced changes of willingness to work, as observed in classical experiments with the D2-antagonist haloperidol.


Assuntos
Aprendizagem da Esquiva/fisiologia , Comportamento de Escolha/fisiologia , Biologia Computacional/métodos , Animais , Gânglios da Base/fisiologia , Simulação por Computador , Dopamina/metabolismo , Humanos , Aprendizagem , Modelos Neurológicos , Motivação , Vias Neurais , Recompensa
13.
PLoS One ; 14(3): e0213094, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30861023

RESUMO

Associative learning is a basic cognitive function by which discrete and often different percepts are linked together. The Rutgers Acquired Equivalence Test investigates a specific kind of associative learning, visually guided equivalence learning. The test consists of an acquisition (pair learning) and a test (rule transfer) phase, which are associated primarily with the function of the basal ganglia and the hippocampi, respectively. Earlier studies described that both fundamentally-involved brain structures in the visual associative learning, the basal ganglia and the hippocampi, receive not only visual but also multisensory information. However, no study has investigated whether there is a priority for multisensory guided equivalence learning compared to unimodal ones. Thus we had no data about the modality-dependence or independence of the equivalence learning. In the present study, we have therefore introduced the auditory- and multisensory (audiovisual)-guided equivalence learning paradigms and investigated the performance of 151 healthy volunteers in the visual as well as in the auditory and multisensory paradigms. Our results indicated that visual, auditory and multisensory guided associative learning is similarly effective in healthy humans, which suggest that the acquisition phase is fairly independent from the modality of the stimuli. On the other hand, in the test phase, where participants were presented with acquisitions that were learned earlier and associations that were until then not seen or heard but predictable, the multisensory stimuli elicited the best performance. The test phase, especially its generalization part, seems to be a harder cognitive task, where the multisensory information processing could improve the performance of the participants.


Assuntos
Aprendizagem por Associação/fisiologia , Gânglios da Base/fisiologia , Hipocampo/fisiologia , Estimulação Acústica , Adulto , Idoso , Percepção Auditiva , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estimulação Luminosa , Percepção Visual , Adulto Jovem
14.
PLoS Comput Biol ; 15(2): e1006782, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30730886

RESUMO

The theory of phase oscillators is an essential tool for understanding population dynamics of pacemaking neurons. GABAergic pacemakers in the substantia nigra pars reticulata (SNr), a main basal ganglia (BG) output nucleus, receive inputs from the direct and indirect pathways at distal and proximal regions of their dendritic arbors, respectively. We combine theory, optogenetic stimulation and electrophysiological experiments in acute brain slices to ask how dendritic properties impact the propensity of the various inputs, arriving at different locations along the dendrite, to recruit or entrain SNr pacemakers. By combining cable theory with sinusoidally-modulated optogenetic activation of either proximal somatodendritic regions or the entire somatodendritic arbor of SNr neurons, we construct an analytical model that accurately fits the empirically measured somatic current response to inputs arising from illuminating the soma and various portions of the dendritic field. We show that the extent of the dendritic tree that is illuminated generates measurable and systematic differences in the pacemaker's phase response curve (PRC), causing a shift in its peak. Finally, we show that the divergent PRCs correctly predict differences in two major features of the collective dynamics of SNr neurons: the fidelity of population responses to sudden step-like changes in inputs; and the phase latency at which SNr neurons are entrained by rhythmic stimulation, which can occur in the BG under both physiological and pathophysiological conditions. Our novel method generates measurable and physiologically meaningful spatial effects, and provides the first empirical demonstration of how the collective responses of SNr pacemakers are determined by the transmission properties of their dendrites. SNr dendrites may serve to delay distal striatal inputs so that they impinge on the spike initiation zone simultaneously with pallidal and subthalamic inputs in order to guarantee a fair competition between the influence of the monosynaptic direct- and polysynaptic indirect pathways.


Assuntos
Gânglios da Base/fisiologia , Plasticidade Neuronal/fisiologia , Potenciais de Ação/fisiologia , Animais , Corpo Estriado , Dendritos , Estimulação Elétrica/métodos , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Inibição Neural/fisiologia , Vias Neurais/fisiologia , Neurônios/fisiologia , Marca-Passo Artificial
15.
Neurochem Int ; 125: 67-73, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30710558

RESUMO

The neostriatum has a mosaic organization consisting of striosome and matrix compartments. It receives glutamatergic excitatory afferents from the cerebral cortex and thalamus. Recent behavioral studies in rats revealed a selectively active medial prefronto-striosomal circuit during cost-benefit decision-making. However, clarifying the input/output organization of striatal compartments has been difficult because of its complex structure. We recently demonstrated that the source of thalamostriatal projections are highly organized in striatal compartments. This finding indicated that the functional properties of striatal compartments are influenced by their cortical and thalamic afferents, presumably with different time latencies. In addition, these afferents likely support the unique dynamics of striosome and matrix compartments. In this manuscript, we review the anatomy of basal ganglia networks with regard to striosome/matrix structure. We place specific focus on thalamostriatal projections at the population and single neuron level.


Assuntos
Gânglios da Base/fisiologia , Córtex Cerebral/fisiologia , Rede Nervosa/fisiologia , Neurônios/fisiologia , Tálamo/fisiologia , Animais , Gânglios da Base/citologia , Córtex Cerebral/citologia , Corpo Estriado/citologia , Corpo Estriado/fisiologia , Humanos , Rede Nervosa/citologia , Neurônios/citologia , Tálamo/citologia
16.
NeuroRehabilitation ; 44(1): 25-35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30741701

RESUMO

BACKGROUND: Intermanual transfer of learning is an important movement basis for a keyboard and instrument playing movement. However, the issue of where neural plastic mechanism occurs in the brain after intermanual transfer training remains both controversial and unresolved. OBJECTIVE: The aim of present study is to investigate the neuroplastic mechanism associated with the interlimb transfer learning from non-dominant hand to dominant hand. METHODS: Twenty healthy right-handed adults were classified into either the control group (no-training) or the experimental group (training serial button-press motor task, SPMT), 5 days a week for two consecutive weeks. SPMT involved pressing the numbers 1, 2, 3, and 4 in a random sequence, which was presented in the monitor screen. Outcome measures included movement accuracy (MA), movement time (MT), and the fMRI data using a 3T MRI scanner. Repeated measures of analysis of variance (ANOVA) and non-parametric tests were used at p <0.05. RESULTS: Motor performances in the MA and MT were significantly more improved in the experimental group than in the control group (p <0.05). Neuroimaging data revealed a distributed subcortical and cortical motor network including the SMA-thalamus (VL/VL)-basal ganglia-cerebellum loop, suggesting a differential and time-dependent neural network utilized during intermanual transfer learning. CONCLUSION: Pre-training intermanual transfer learning involved a form of declarative (or explicit) motor learning, which was primarily mediated by the cortical motor network, whereas post-training involved a form of procedural knowledge, which activated subcortical and cortical motor network regions, including the SMA-thalamus (VL/VL)-basal ganglia-cerebellum loop.


Assuntos
Lateralidade Funcional/fisiologia , Imagem por Ressonância Magnética/métodos , Destreza Motora/fisiologia , Plasticidade Neuronal/fisiologia , Desempenho Psicomotor/fisiologia , /fisiologia , Adulto , Gânglios da Base/fisiologia , Cerebelo/fisiologia , Feminino , Mãos/fisiologia , Humanos , Masculino , Estudos Prospectivos , Tálamo/fisiologia , Adulto Jovem
17.
Neurosci Biobehav Rev ; 100: 19-34, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30790636

RESUMO

Despite wide evidence suggesting anatomical and functional interactions between cortex, cerebellum and basal ganglia, the learning processes operating within them --often viewed as respectively unsupervised, supervised and reinforcement learning-- are studied in isolation, neglecting their strong interdependence. We discuss how those brain areas form a highly integrated system combining different learning mechanisms into an effective super-learning process supporting the acquisition of flexible motor behaviour. The term "super-learning" does not indicate a new learning paradigm. Rather, it refers to the fact that different learning mechanisms act in synergy as they: (a) affect neural structures often relying on the widespread action of neuromodulators; (b) act within various stages of cortical/subcortical pathways that are organised in pipeline to support multiple sensation-to-action mappings operating at different levels of abstraction; (c) interact through the reciprocal influence of the output compartments of different brain structures, most notably in the cerebello-cortical and basal ganglia-cortical loops. Here we articulate this new hypothesis and discuss empirical evidence supporting it by specifically referring to motor adaptation and sequence learning.


Assuntos
Gânglios da Base/fisiologia , Cerebelo/fisiologia , Córtex Cerebral/fisiologia , Aprendizagem/fisiologia , Animais , Humanos , Motivação/fisiologia , Vias Neurais/fisiologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-30804759

RESUMO

It has been suggested that the function of the claustrum (CL) may be to orchestrate and integrate the activity of the different cortical areas that are involved in a particular function by boosting the synchronized oscillations that occur between these areas. We propose here a model of how this may be done, thanks to the unique synaptic morphology of the CL and its excitatory and inhibitory connections with most cortical areas. Using serial visual search as an example, we describe how the functional anatomy of the claustral connections can potentially execute the sequential activation of the representations of objects that are being processed serially. We also propose that cross-frequency coupling (CFC) between low frequency signals from CL and higher frequency oscillations in the cortical areas will be an efficient means of CL modulating neural activity across multiple brain regions in synchrony. This model is applicable to the wide range of functions one performs, from simple object recognition to reading and writing, listening to or performing music, etc.


Assuntos
Gânglios da Base/fisiologia , Córtex Cerebral/citologia , Modelos Neurológicos , Vias Neurais/fisiologia , Neurônios/fisiologia , Humanos , Estimulação Luminosa , Percepção Visual
19.
Neurobiol Dis ; 128: 19-30, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-29524600

RESUMO

The interest in the pedunculopontine tegmental nucleus (PPTg), a structure located in the brainstem at the level of the pontomesencephalic junction, has greatly increased in recent years because it is involved in the regulation of physiological functions that fail in Parkinson's disease and because it is a promising target for deep brain stimulation in movement disorders. The PPTg is highly interconnected with the main basal ganglia nuclei and relays basal ganglia activity to thalamic and brainstem nuclei and to spinal effectors. In this review, we address the functional role of the main PPTg outputs directed to the basal ganglia, thalamus, cerebellum and spinal cord. Together, the data that we discuss show that the PPTg may influence thalamocortical activity and spinal motoneuron excitability through its ascending and descending output fibers, respectively. Cerebellar nuclei may also relay signals from the PPTg to thalamic and brainstem nuclei. In addition to participating in motor functions, the PPTg participates in arousal, attention, action selection and reward mechanisms. Finally, we discuss the possibility that the PPTg may be involved in excitotoxic degeneration of the dopaminergic neurons of the substantia nigra through the glutamatergic monosynaptic input that it provides to these neurons.


Assuntos
Gânglios da Base/fisiologia , Neurônios/fisiologia , Núcleo Tegmental Pedunculopontino/fisiologia , Animais , Atenção/fisiologia , Humanos , Vias Neurais/fisiologia , Recompensa
20.
Neurobiol Learn Mem ; 160: 21-31, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29660400

RESUMO

Memory consolidation is a gradual process through which episodic memories become incorporated into long-term 'semantic' representations. It likely involves reactivation of neural activity encoding the recent experience during non-REM sleep. A critical prerequisite for memory consolidation is precise coordination of reactivation events between the hippocampus and cortical/subcortical structures, facilitated by the coupling of local field potential (LFP) oscillations (slow oscillations, sleep spindles and sharp wave/ripples) between these structures. We review the rapidly expanding literature on the qualitative and quantitative aspects of hippocampal oscillatory and neuronal coupling with cortical/subcortical structures in the context of memory reactivation. Reactivation in the hippocampus and cortical/subcortical structures is tightly coupled with sharp wave/ripples. Hippocampal-cortical/subcortical coupling is rich in dimensionality and this dimensionality is likely underestimated due to the limitations of the current methodology.


Assuntos
Gânglios da Base/fisiologia , Ondas Encefálicas/fisiologia , Córtex Cerebral/fisiologia , Hipocampo/fisiologia , Consolidação da Memória/fisiologia , Fases do Sono/fisiologia , Animais , Humanos
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