scholarly journals The Dopamine System and Automatization of Movement Sequences: A Review With Relevance for Speech and Stuttering

2021 ◽  
Vol 15 ◽  
Author(s):  
Per A. Alm
Keyword(s):  
Basal Ganglia ◽  
Building Blocks ◽  
Speech Disorders ◽  
Theoretical Development ◽  
Neural Basis ◽  
Dopamine System ◽  
Movement Sequences ◽  
Vertebrate Brain ◽  
Human Disorders ◽  
Cerebral Dopamine

The last decades of research have gradually elucidated the complex functions of the dopamine system in the vertebrate brain. The multiple roles of dopamine in motor function, learning, attention, motivation, and the emotions have been difficult to reconcile. A broad and detailed understanding of the physiology of cerebral dopamine is of importance in understanding a range of human disorders. One of the core functions of dopamine involves the basal ganglia and the learning and execution of automatized sequences of movements. Speech is one of the most complex and highly automatized sequential motor behaviors, though the exact roles that the basal ganglia and dopamine play in speech have been difficult to determine. Stuttering is a speech disorder that has been hypothesized to be related to the functions of the basal ganglia and dopamine. The aim of this review was to provide an overview of the current understanding of the cerebral dopamine system, in particular the mechanisms related to motor learning and the execution of movement sequences. The primary aim was not to review research on speech and stuttering, but to provide a platform of neurophysiological mechanisms, which may be utilized for further research and theoretical development on speech, speech disorders, and other behavioral disorders. Stuttering and speech are discussed here only briefly. The review indicates that a primary mechanism for the automatization of movement sequences is the merging of isolated movements into chunks that can be executed as units. In turn, chunks can be utilized hierarchically, as building blocks of longer chunks. It is likely that these mechanisms apply also to speech, so that frequent syllables and words are produced as motor chunks. It is further indicated that the main learning principle for sequence learning is reinforcement learning, with the phasic release of dopamine as the primary teaching signal indicating successful sequences. It is proposed that the dynamics of the dopamine system constitute the main neural basis underlying the situational variability of stuttering.

scholarly journals The Lamprey Forebrain – Evolutionary Implications

2021 ◽  
pp. 1-16
Author(s):  
Shreyas M. Suryanarayana ◽  
Juan Pérez-Fernández ◽  
Brita Robertson ◽  
Sten Grillner
Keyword(s):  
Basal Ganglia ◽  
Sensory Integration ◽  
Critical Role ◽  
Detailed Comparison ◽  
Common Ancestry ◽  
Dopamine System ◽  
Cortical Areas ◽  
Neural Processes ◽  
Living Group ◽  
Selection Of

The forebrain plays a critical role in a broad range of neural processes encompassing sensory integration and initiation/selection of behaviour. The forebrain functions through an interaction between different cortical areas, the thalamus, the basal ganglia with the dopamine system, and the habenulae. The ambition here is to compare the mammalian forebrain with that of the lamprey representing the oldest now living group of vertebrates, by a review of earlier studies. We show that the lamprey dorsal pallium has a motor, a somatosensory, and a visual area with retinotopic representation. The lamprey pallium was previously thought to be largely olfactory. There is also a detailed similarity between the lamprey and mammals with regard to other forebrain structures like the basal ganglia in which the general organisation, connectivity, transmitters and their receptors, neuropeptides, and expression of ion channels are virtually identical. These initially unexpected results allow for the possibility that many aspects of the basic design of the vertebrate forebrain had evolved before the lamprey diverged from the evolutionary line leading to mammals. Based on a detailed comparison between the mammalian forebrain and that of the lamprey and with due consideration of data from other vertebrate groups, we propose a compelling account of a pan-vertebrate schema for basic forebrain structures, suggesting a common ancestry of over half a billion years of vertebrate evolution.

scholarly journals Expression of FoxP2 in the basal ganglia regulates vocal motor sequences in the adult songbird

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lei Xiao ◽  
Devin P. Merullo ◽  
Therese M. I. Koch ◽  
Mou Cao ◽  
Marissa Co ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Basal Ganglia ◽  
Dopamine Receptor ◽  
Speech Disorders ◽  
Receptor Expression ◽  
Vocal Development ◽  
Motor Actions

AbstractDisruption of the transcription factor FoxP2, which is enriched in the basal ganglia, impairs vocal development in humans and songbirds. The basal ganglia are important for the selection and sequencing of motor actions, but the circuit mechanisms governing accurate sequencing of learned vocalizations are unknown. Here, we show that expression of FoxP2 in the basal ganglia is vital for the fluent initiation and termination of birdsong, as well as the maintenance of song syllable sequencing in adulthood. Knockdown of FoxP2 imbalances dopamine receptor expression across striatal direct-like and indirect-like pathways, suggesting a role of dopaminergic signaling in regulating vocal motor sequencing. Confirming this prediction, we show that phasic dopamine activation, and not inhibition, during singing drives repetition of song syllables, thus also impairing fluent initiation and termination of birdsong. These findings demonstrate discrete circuit origins for the dysfluent repetition of vocal elements in songbirds, with implications for speech disorders.

scholarly journals Large-area display textiles integrated with functional systems

2020 ◽  
Author(s):  
Huisheng Peng ◽  
Xiang Shi ◽  
Yong Zuo ◽  
Peng Zhai ◽  
Jiahao Shen ◽  
...  
Keyword(s):  
Building Blocks ◽  
Speech Disorders ◽  
Communication Tool ◽  
Electronic Textiles ◽  
Large Area ◽  
Practical Applications ◽  
Contact Points ◽  
Luminescent Coating ◽  
And Function ◽  
The Internet Of Things

Abstract Displays are basic building blocks of modern electronics1,2. Integrating displays into textiles offers exciting opportunities for smart electronic textiles – the ultimate form of wearables poised to change the way we interact with electronic devices3-6. Display textiles serve to bridge human-machine interactions7-9, offering for instance, a real-time communication tool for individuals with voice or speech disorders. Electronic textiles capable of communicating10, sensing11,12 and supplying electricity13,14 have been reported previously. However, textiles with functional, large-area displays have not been achieved so far because obtaining small illuminating units that are both durable and easy to assemble over a wide area is challenging. Here, we report a 6 m (L) * 25 cm (W) display textile containing 500000 electroluminescent (EL) units narrowly spaced to ~800 μm. Weaving conductive weft and luminescent warp fibres forms micron-scale EL units at the weft-warp contact points. Brightness between EL units deviates by < 6.3% and remains stable even when the textile is bent, stretched or pressed. We attribute this uniform and stable lighting to the smooth luminescent coating around the warp fibres and homogenous electric field distribution at the contact points. Our display textile is flexible and breathable and withstands repeatable machine-washing, making them suitable for practical applications. We show an integrated textile system consisting of display, keyboard and power supply can serve as a communication tool, which could potentially drive the Internet of Things in various areas including healthcare. Our approach unifies the fabrication and function of electronic devices with textiles, and we expect weaving fibre materials to shape the next-generation electronics.

The Neural Basis of Escape Behavior in Vertebrates

2020 ◽  
Vol 43 (1) ◽  
pp. 417-439 ◽  
Author(s):  
Tiago Branco ◽  
Peter Redgrave
Keyword(s):  
Neural Circuits ◽  
Escape Behavior ◽  
Building Blocks ◽  
Normative Theory ◽  
Neural Systems ◽  
Adaptive Behaviors ◽  
Neural Basis ◽  
Sensory Stimuli ◽  
Evolutionarily Conserved ◽  
Escape Behaviors

Escape is one of the most studied animal behaviors, and there is a rich normative theory that links threat properties to evasive actions and their timing. The behavioral principles of escape are evolutionarily conserved and rely on elementary computational steps such as classifying sensory stimuli and executing appropriate movements. These are common building blocks of general adaptive behaviors. Here we consider the computational challenges required for escape behaviors to be implemented, discuss possible algorithmic solutions, and review some of the underlying neural circuits and mechanisms. We outline shared neural principles that can be implemented by evolutionarily ancient neural systems to generate escape behavior, to which cortical encephalization has been added to allow for increased sophistication and flexibility in responding to threat.

scholarly journals Neural basis for hand muscle synergies in the primate spinal cord

2017 ◽  
Vol 114 (32) ◽  
pp. 8643-8648 ◽  
Author(s):  
Tomohiko Takei ◽  
Joachim Confais ◽  
Saeka Tomatsu ◽  
Tomomichi Oya ◽  
Kazuhiko Seki
Keyword(s):  
Spinal Cord ◽  
Neural Control ◽  
Cervical Spinal Cord ◽  
Building Blocks ◽  
Muscle Synergies ◽  
Muscle Coordination ◽  
Neural Basis ◽  
Population Activity ◽  
Hand Functions ◽  
Hand Muscle

Grasping is a highly complex movement that requires the coordination of multiple hand joints and muscles. Muscle synergies have been proposed to be the functional building blocks that coordinate such complex motor behaviors, but little is known about how they are implemented in the central nervous system. Here we demonstrate that premotor interneurons (PreM-INs) in the primate cervical spinal cord underlie the spatiotemporal patterns of hand muscle synergies during a voluntary grasping task. Using spike-triggered averaging of hand muscle activity, we found that the muscle fields of PreM-INs were not uniformly distributed across hand muscles but rather distributed as clusters corresponding to muscle synergies. Moreover, although individual PreM-INs have divergent activation patterns, the population activity of PreM-INs reflects the temporal activation of muscle synergies. These findings demonstrate that spinal PreM-INs underlie the muscle coordination required for voluntary hand movements in primates. Given the evolution of neural control of primate hand functions, we suggest that spinal premotor circuits provide the fundamental coordination of multiple joints and muscles upon which more fractionated control is achieved by superimposed, phylogenetically newer, pathways.

scholarly journals Redistribution of neural phase coherence reflects establishment of feedforward map in speech motor adaptation

2015 ◽  
Vol 113 (7) ◽  
pp. 2471-2479 ◽  
Author(s):  
Ranit Sengupta ◽  
Sazzad M. Nasir
Keyword(s):  
Motor Learning ◽  
Motor Adaptation ◽  
Brain Regions ◽  
Speech Disorders ◽  
Phase Coherence ◽  
Vowel Sound ◽  
Neural Basis ◽  
Neuronal Communication ◽  
Speech Learning ◽  
Speech Motor

Despite recent progress in our understanding of sensorimotor integration in speech learning, a comprehensive framework to investigate its neural basis is lacking at behaviorally relevant timescales. Structural and functional imaging studies in humans have helped us identify brain networks that support speech but fail to capture the precise spatiotemporal coordination within the networks that takes place during speech learning. Here we use neuronal oscillations to investigate interactions within speech motor networks in a paradigm of speech motor adaptation under altered feedback with continuous recording of EEG in which subjects adapted to the real-time auditory perturbation of a target vowel sound. As subjects adapted to the task, concurrent changes were observed in the theta-gamma phase coherence during speech planning at several distinct scalp regions that is consistent with the establishment of a feedforward map. In particular, there was an increase in coherence over the central region and a decrease over the fronto-temporal regions, revealing a redistribution of coherence over an interacting network of brain regions that could be a general feature of error-based motor learning in general. Our findings have implications for understanding the neural basis of speech motor learning and could elucidate how transient breakdown of neuronal communication within speech networks relates to speech disorders.

Basal ganglia neural mechanisms of natural movement sequences

2004 ◽  
Vol 82 (8-9) ◽  
pp. 732-739 ◽  
Author(s):  
J Wayne Aldridge ◽  
Kent C Berridge ◽  
Alyssa R Rosen
Keyword(s):  
Basal Ganglia ◽  
Neural Mechanisms ◽  
Sequential Patterns ◽  
Striatal Neurons ◽  
Warm Up ◽  
Movement Sequences ◽  
Natural Movement ◽  
Baseline Levels ◽  
Instinctive Behavior ◽  
Complex Movement

Natural rodent grooming and other instinctive behavior serves as a natural model of complex movement sequences. Rodent grooming has syntactic (rule-driven) sequences and more random movement patterns. Both incorporate the same movements—only the serial structure differs. Recordings of neural activity in the dorsolateral striatum and the substantia nigra pars reticulata indicate preferential activation during syntactic sequences over more random sequences. Neurons that are responsive during syntactic grooming sequences are often unresponsive or have reverse activation profiles during kinematically similar movements that occur in flexible or random grooming sequences. Few neurons could be categorized as strictly movement related—instead they were activated only in the context of particular sequential patterns of movements. Particular sequential patterns included "syntactic chain" grooming sequences of paw, head, and body movements and also "warm-up" sequences, which consist of head and body/limb movements that precede locomotion after a period of quiet resting (Golani 1992). Activation during warm-up was less intense and less frequent than during grooming sequences, but both sequences activated neurons above baseline levels, and the same neurons sometimes responded to both sequences. The fact that striatal neurons code 2 natural sequences which are made up of different constituent movements suggests that the basal ganglia may have a generalized role in sequence control. The basal ganglia are modulated by the context of the sequence and may play an executive function in the complex natural patterns of sequenced behaviour.Key words: movement, basal ganglia, striatum, movement sequences, sensorimotor behaviour.

scholarly journals Tardive Dyskinesia and Akathasia: A Dopamine System Theory Clinical Review

2019 ◽  
Vol 4 (1) ◽  
Keyword(s):  
System Theory ◽  
Basal Ganglia ◽  
Tardive Dyskinesia ◽  
Dopamine Receptors ◽  
Clinical Review ◽  
Dopamine Agonists ◽  
First Generation ◽  
Second Generation ◽  
Dopamine System

Long term use of first generation anti-psychotics (FGAs) have been theorized in the formation of motion disorders Tardive Dyskinesia and Akathasia and due to the breakdown in the extra pyramidal system (EPS) located in the Basal Ganglia [1]. The second generation anti-psychotics (SGAs) were sourced to be the “treatment” of TD by blocking dopamine receptors with dopamine agonists of the D2-D5 receptors while also being seen as the genesis of AK. However, the blocking of the receptors in both motion disorders is a theory known as the dopamine blockage theory, despite the intermingle of other neurotransmitters such as Serotonin and Norepinephrine [2]

scholarly journals The neural bases of vertebrate motor behaviour through the lens of evolution

2021 ◽  
Vol 377 (1844) ◽  
Author(s):  
Shreyas M. Suryanarayana ◽  
Brita Robertson ◽  
Sten Grillner
Keyword(s):  
Central Pattern Generators ◽  
Phylogenetic Position ◽  
Neural Basis ◽  
Theme Issue ◽  
Systems Neuroscience ◽  
Vertebrate Brain ◽  
Primary Driver ◽  
Neural Bases ◽  
Pattern Generators ◽  
Ancestral Vertebrate

The primary driver of the evolution of the vertebrate nervous system has been the necessity to move, along with the requirement of controlling the plethora of motor behavioural repertoires seen among the vast and diverse vertebrate species. Understanding the neural basis of motor control through the perspective of evolution, mandates thorough examinations of the nervous systems of species in critical phylogenetic positions. We present here, a broad review of studies on the neural motor infrastructure of the lamprey, a basal and ancient vertebrate, which enjoys a unique phylogenetic position as being an extant representative of the earliest group of vertebrates. From the central pattern generators in the spinal cord to the microcircuits of the pallial cortex, work on the lamprey brain over the years, has provided detailed insights into the basic organization (a bauplan ) of the ancestral vertebrate brain, and narrates a compelling account of common ancestry of fundamental aspects of the neural bases for motion control, maintained through half a billion years of vertebrate evolution. This article is part of the theme issue ‘Systems neuroscience through the lens of evolutionary theory’.

Biomimetic systems

2018 ◽  
Author(s):  
Tony J. Prescott
Keyword(s):  
Phylogenetic Tree ◽  
Building Blocks ◽  
Bilateral Symmetry ◽  
Biomimetic Systems ◽  
Vertebrate Brain ◽  
Living Things ◽  
Branching Points ◽  
History Of

So far in this volume we have considered the nature of living things and some of their key building blocks and capabilities. This has set the stage for the current section and the next where we will describe some exemplar integrated biomimetic and biohybrid systems—living machines. To place these contributions in some additional context this introduction briefly reviews the history of life and of its variety, noting some of the critical branching points in the phylogenetic tree, identifying some of the organisms that have been the focus of research on biomimetic systems, and exploring why they might be seen to be important or pivotal. We begin with the first replicators, then consider bacterial colonies, the emergence of multicellularity and of bilateral symmetry, and conclude with a brief discussion of biomimetics applied to vertebrate brain and body plans including those of humans.

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