4D Hyperspherical Harmonic (HyperSPHARM) Representation of Multiple Disconnected Brain Subcortical Structures

Emotions arise from activations of specialized neuronal populations in several parts of the cerebral cortex, notably the anterior cingulate, insula, ventromedial prefrontal, and subcortical structures, such as the amygdala, ventral striatum, putamen, caudate nucleus, and ventral tegmental area. Feelings are conscious, emotional experiences of these activations that contribute to neuronal networks mediating thoughts, language, and behavior, thus enhancing the ability to predict, learn, and reappraise stimuli and situations in the environment based on previous experiences. Contemporary theories of emotion converge around the key role of the amygdala as the central subcortical emotional brain structure that constantly evaluates and integrates a variety of sensory information from the surroundings and assigns them appropriate values of emotional dimensions, such as valence, intensity, and approachability. The amygdala participates in the regulation of autonomic and endocrine functions, decision-making and adaptations of instinctive and motivational behaviors to changes in the environment through implicit associative learning, changes in short- and long-term synaptic plasticity, and activation of the fight-or-flight response via efferent projections from its central nucleus to cortical and subcortical structures.

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Sleep in Normal Aging, Homeostatic and Circadian Regulation and Vulnerability to Sleep Deprivation

Brain Sciences ◽

10.3390/brainsci11081003 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1003

Author(s):

Jacques Taillard ◽

Claude Gronfier ◽

Stéphanie Bioulac ◽

Pierre Philip ◽

Patricia Sagaspe

Keyword(s):

Older Adults ◽

Sleep Deprivation ◽

Health Management ◽

Nrem Sleep ◽

Early Morning ◽

Subcortical Structures ◽

Wake Time ◽

Adverse Health Outcomes ◽

Neurobehavioral Function ◽

Age Related

In the context of geriatric research, a growing body of evidence links normal age-related changes in sleep with many adverse health outcomes, especially a decline in cognition in older adults. The most important sleep alterations that continue to worsen after 60 years involve sleep timing, (especially early wake time, phase advance), sleep maintenance (continuity of sleep interrupted by numerous awakenings) and reduced amount of sigma activity (during non-rapid eye movement (NREM) sleep) associated with modifications of sleep spindle characteristics (density, amplitude, frequency) and spindle–Slow Wave coupling. After 60 years, there is a very clear gender-dependent deterioration in sleep. Even if there are degradations of sleep after 60 years, daytime wake level and especially daytime sleepiness is not modified with age. On the other hand, under sleep deprivation condition, older adults show smaller cognitive impairments than younger adults, suggesting an age-related lower vulnerability to extended wakefulness. These sleep and cognitive age-related modifications would be due to a reduced homeostatic drive and consequently a reduced sleep need, an attenuation of circadian drive (reduction of sleep forbidden zone in late afternoon and wake forbidden zone in early morning), a modification of the interaction of the circadian and homeostatic processes and/or an alteration of subcortical structures involved in generation of circadian and homeostatic drive, or connections to the cerebral cortex with age. The modifications and interactions of these two processes with age are still uncertain, and still require further investigation. The understanding of the respective contribution of circadian and homeostatic processes in the regulation of neurobehavioral function with aging present a challenge for improving health, management of cognitive decline and potential early chronobiological or sleep-wake interventions.

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A probabilistic atlas of the human ventral tegmental area (VTA) based on 7 Tesla MRI data

Brain Structure and Function ◽

10.1007/s00429-021-02231-w ◽

2021 ◽

Vol 226 (4) ◽

pp. 1155-1167 ◽

Cited By ~ 1

Author(s):

Anne C. Trutti ◽

Laura Fontanesi ◽

Martijn J. Mulder ◽

Pierre-Louis Bazin ◽

Bernhard Hommel ◽

...

Keyword(s):

Ventral Tegmental Area ◽

Region Of Interest ◽

Reward Processing ◽

7 Tesla ◽

Subcortical Structures ◽

7 Tesla Mri ◽

Subcortical Nuclei ◽

Ventral Tegmental ◽

The Brain

AbstractFunctional magnetic resonance imaging (fMRI) BOLD signal is commonly localized by using neuroanatomical atlases, which can also serve for region of interest analyses. Yet, the available MRI atlases have serious limitations when it comes to imaging subcortical structures: only 7% of the 455 subcortical nuclei are captured by current atlases. This highlights the general difficulty in mapping smaller nuclei deep in the brain, which can be addressed using ultra-high field 7 Tesla (T) MRI. The ventral tegmental area (VTA) is a subcortical structure that plays a pivotal role in reward processing, learning and memory. Despite the significant interest in this nucleus in cognitive neuroscience, there are currently no available, anatomically precise VTA atlases derived from 7 T MRI data that cover the full region of the VTA. Here, we first provide a protocol for multimodal VTA imaging and delineation. We then provide a data description of a probabilistic VTA atlas based on in vivo 7 T MRI data.

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Anatomy of Motor Learning. II. Subcortical Structures and Learning by Trial and Error

Journal of Neurophysiology ◽

10.1152/jn.1997.77.3.1325 ◽

1997 ◽

Vol 77 (3) ◽

pp. 1325-1337 ◽

Cited By ~ 294

Author(s):

M. Jueptner ◽

C. D. Frith ◽

D. J. Brooks ◽

R.S.J. Frackowiak ◽

R. E. Passingham

Keyword(s):

Motor Learning ◽

Response Times ◽

Cerebellar Nuclei ◽

Selection Task ◽

Systematic Change ◽

Trial And Error ◽

Subcortical Structures ◽

Learning Condition ◽

Positron Emission ◽

New Learning

Jueptner, M., C. D. Frith, D. J. Brooks, R.S.J. Frackowiak, and R. E. Passingham. Anatomy of motor learning. II. Subcortical structures and learning by trial and error. J. Neurophysiol. 77: 1325–1337, 1997. We used positron emission tomography to study motor learning by trial and error. Subjects learned sequences of eight finger movements. Tones generated by a computer told the subjects whether any particular move was correct or incorrect. A control condition was used in which the subjects generated moves, but there was no feeback to indicate success or failure, and so no learning occured. In this condition (free selection) the subjects were required to make a finger movement on each trial and to vary the movements randomly over trials. The subjects had a free choice of which finger to move on any one trial. On this task there was no systematic change in responses over trials and no change in the response times. Two other conditions were included. In one the subjects repetitively moved the same finger on all trials and in a baseline condition the subjects heard the pacing tones and auditory feedback but made no movements. Comparing new learning with the free selection task, there was a small activation in the right prefrontal cortex. This may reflect the fact that in new learning, but not free selection, the subjects rehearse past moves and adapt their responses accordingly. The caudate nucleus was strongly activated during new learning. It is suggested that this activity may be related either to mental rehearsal or to reinforcement of the movements as a consequence of the outcomes. The putamen was activated anteriorly on the free selection task and more posteriorly when the subjects repetitively made the same movement. It is suggested that the differences in the location of the peak activation in the striatum may represent the operation of different corticostriatal loops. The cerebellar nuclei (bilaterally) and vermis were more active in the new learning condition than during the performance of the free selection task. There was no difference in the activation of the cerebellum when the free selection task was compared with repetitive performance of the same movement. We tentatively suggest that the basal ganglia may be involved in the specification of movement on the basis of memory of either the movements or the outcomes, but that the cerebellum may be more directly involved in changes in the parameters of movement execution.

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Contribution to the evaluation of language disturbances in subcortical lesions: a piloty study

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x2004000100009 ◽

2004 ◽

Vol 62 (1) ◽

pp. 51-57 ◽

Cited By ~ 17

Author(s):

Márcia Radanovic ◽

Letícia Lessa Mansur ◽

Mariana Jardim Azambuja ◽

Cláudia Sellitto Porto ◽

Milberto Scaff

Keyword(s):

Executive Functions ◽

Cognitive Abilities ◽

Wisconsin Card Sorting Test ◽

Cognitive Networks ◽

Vascular Lesions ◽

Card Sorting ◽

Subcortical Structures ◽

Boston Naming Test ◽

Language Abilities ◽

Trail Making

Subcortical structures are in a strategic functional position within the cognitive networks and their lesion can interfere with a great number of functions. In this study, we describe fourteen subjects with exclusively subcortical vascular lesions (eight in the basal ganglia and six in the thalamus) and the interrelation between their language alterations and other cognitive abilities, as attention, memory and frontal executive functions. All patients were evaluated through the following batteries: Boston Diagnostic Aphasia Examination, Boston Naming Test, Token Test, Benton Visual Retention Test, Trail Making, Wisconsin Card Sorting Test and a frontal scripts task. All patients underwent MRI and twelve underwent SPECT. Results show that these patients present impairment in several cognitive domains, especially attention and executive functions. These alterations affect language abilities, and this fact must be considered in the rehabilitation efforts.

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Strengthened Corticosubcortical Functional Connectivity during Muscle Fatigue

Neural Plasticity ◽

10.1155/2016/1726848 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Zhiguo Jiang ◽

Xiao-Feng Wang ◽

Guang H. Yue

Keyword(s):

Motor Control ◽

Functional Connectivity ◽

Quantile Regression ◽

Muscle Fatigue ◽

Motor Performance ◽

Primary Motor Cortex ◽

Motor Task ◽

Voluntary Contraction ◽

Control Network ◽

Subcortical Structures

The present study examined functional connectivity (FC) between functional MRI (fMRI) signals of the primary motor cortex (M1) and each of the three subcortical neural structures, cerebellum (CB), basal ganglia (BG), and thalamus (TL), during muscle fatigue using the quantile regression technique. Understanding activation relation between the subcortical structures and the M1 during prolonged motor performance should help delineate how central motor control network modulates acute perturbations at peripheral sensorimotor system such as muscle fatigue. Ten healthy subjects participated in the study and completed a 20-minute intermittent handgrip motor task at 50% of their maximal voluntary contraction (MVC) level. Quantile regression analyses were carried out to compare the FC between the contralateral (left) M1 and CB, BG, and TL in the minimal (beginning 100 s) versus significant (ending 100 s) fatigue stages. Widespread, statistically significant increases in FC were found in bilateral BG, CB, and TL with the left M1 during significant versus minimal fatigue stages. Our results imply that these subcortical nuclei are critical components in the motor control network and actively involved in modulating voluntary muscle fatigue, possibly, by working together with the M1 to strengthen the descending central command to prolong the motor performance.

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