scholarly journals Symptomatic Dystonias Associated with Structural Brain Lesions: Report of 16 Cases

1996 ◽  
Vol 23 (1) ◽  
pp. 53-56 ◽  
Author(s):  
Vladimir S. Kostià ◽  
Marina Stojanovié-Svetel ◽  
Aleksandra Kacar
Keyword(s):  
Basal Ganglia ◽  
Caudate Nucleus ◽  
Brain Lesions ◽  
Focal Dystonia ◽  
The Brain ◽  
Insight Into ◽  
Structural Brain

ABSTRACT:Background:Symptomatic (secondary) dystonias associated isolated lesions in the brain provide insight into etiopathogenesis of the idiopathic form of dystonia and are a basis for establishing the possible correlation between the anatomy of a lesion and the type of dystonia according to muscles affected.Methods:In 358 patients with differently distributed dystonias, a group of 16 patients (4.5%) was encountered in whom dystonia was associated with focal brain lesions.Results:Of the 16 patients, 3 patients had generalized, 3 segmental and 4 hemidystonia, while the remaining 6 patients had focal dystonia. The most frequent etiologies were infarction in 7, and tumor in 4 patients. These lesions were usually found in the lenticular and caudate nucleus, thalamus, and in the case of blepharospasm in the upper brainstem.Conclusions:Our results support the suggestion that dystonia is caused by a dysfunction of the basal ganglia.

scholarly journals The caudate nucleus controls coordinated patterns of adaptive, context-dependent adjustments to complex decisions

2019 ◽  
Author(s):  
Takahiro Doi ◽  
Yunshu Fan ◽  
Joshua I. Gold ◽  
Long Ding
Keyword(s):  
Basal Ganglia ◽  
Caudate Nucleus ◽  
Decision Process ◽  
Visual Motion ◽  
Electrical Microstimulation ◽  
Visual Evidence ◽  
Sensory Evidence ◽  
Reward Information ◽  
Adaptive Decision Making ◽  
The Brain

AbstractOur decisions often need to balance what we observe and what we desire. However, our understanding of how and where in the brain such decisions are made remains limited. A prime candidate for integrating sensory observations and desired rewards, and a focus of many modeling studies, is the basal ganglia pathway, which is known to make separate contributions to perceptual decisions that require the interpretation of uncertain sensory evidence and value-based decisions that select among outcome options 1-16. Here we report direct evidence for a causal role for a major input station of the basal ganglia, the caudate nucleus, in incorporating reward context and uncertain visual evidence to guide adaptive decision-making. In monkeys making saccadic decisions based on visual motion evidence and asymmetric reward-choice associations 17, single caudate neurons encoded information about both the visual evidence and the asymmetric rewards. Electrical microstimulation at caudate sites with task-modulated activity during motion viewing affected how the visual and reward information was used to form the decision. The microstimulation effects included coordinated changes in multiple computational components of the decision process, mimicking the monkeys’ voluntary adjustments in response to the asymmetric reward contexts. These results imply that the caudate nucleus plays key roles in coordinating the deliberative decision process that balances external evidence and internal preferences to guide adaptive behavior.

scholarly journals Neural Encoding of Objects Relevant for Navigation and Resting State Correlations with Navigational Ability

2011 ◽  
Vol 23 (12) ◽  
pp. 3841-3854 ◽  
Author(s):  
Joost Wegman ◽  
Gabriele Janzen
Keyword(s):  
Functional Connectivity ◽  
Caudate Nucleus ◽  
Resting State ◽  
Neural Correlates ◽  
Parahippocampal Gyrus ◽  
Neural Encoding ◽  
Decision Points ◽  
Brain Responses ◽  
The Brain ◽  
Insight Into

Objects along a route can help us to successfully navigate through our surroundings. Previous neuroimaging research has shown that the parahippocampal gyrus (PHG) distinguishes between objects that were previously encountered at navigationally relevant locations (decision points) and irrelevant locations (nondecision points) during simple object recognition. This study aimed at unraveling how this neural marking of objects relevant for navigation is established during learning and postlearning rest. Twenty-four participants were scanned using fMRI while they were viewing a route through a virtual environment. Eye movements were measured, and brain responses were time-locked to viewing each object. The PHG showed increased responses to decision point objects compared with nondecision point objects during route learning. We compared functional connectivity between the PHG and the rest of the brain in a resting state scan postlearning with such a scan prelearning. Results show that functional connectivity between the PHG and the hippocampus is positively related to participants' self-reported navigational ability. On the other hand, connectivity with the caudate nucleus correlated negatively with navigational ability. These results are in line with a distinction between egocentric and allocentric spatial representations in the caudate nucleus and the hippocampus, respectively. Our results thus suggest a relation between navigational ability and a neural preference for a specific type of spatial representation. Together, these results show that the PHG is immediately involved in the encoding of navigationally relevant object information. Furthermore, they provide insight into the neural correlates of individual differences in spatial ability.

Focal brain syndromes in neuropsychiatry

2020 ◽  
pp. 453-462
Author(s):  
Paul Shotbolt
Keyword(s):  
Eighteenth Century ◽  
Prefrontal Cortex ◽  
Basal Ganglia ◽  
Case Studies ◽  
Medial Prefrontal Cortex ◽  
Brain Lesions ◽  
Anatomical Localization ◽  
Psychiatric Conditions ◽  
Neurological Conditions ◽  
The Brain

The idea that the brain’s different regions are responsible for specific functions was first described by François Chaussier in the eighteenth century, leading to the neuroscientific delineation of the lobes. This chapter goes on to describe the functions of different regions of the brain, before listing the neurological conditions which can result from damage to each region, such as spasticity and hyperreflexia from lesions on the medial prefrontal cortex, or Parkinson’s disease and Wilson’s disease from damage to the basal ganglia. Case studies are used to show the behavioural changes which can arise from such lesions and to demonstrate that similar groupings of psychiatric responses to lesions in different areas, paired with the rarity of truly focal brain lesions, make the process of anatomical localization more complicated with psychiatric conditions than neurological ones.

Voluntary Motor Control

2017 ◽  
Author(s):  
Peggy Mason
Keyword(s):  
Motor Control ◽  
Basal Ganglia ◽  
Building Blocks ◽  
Muscle Contractions ◽  
Brain Lesions ◽  
Upright Posture ◽  
Voluntary Motor ◽  
Motor Commands ◽  
Cortical Regions ◽  
The Brain

The motor hierarchy uses muscle twitches as building blocks for complex and consciously driven actions requiring neocortical involvement. Cortical regions operate in concert with the cerebellum and basal ganglia to generate well-timed and organized muscle contractions that produce movements, ranging from simple to complex. Once imbued with meaning, these movements are considered actions. Adjustments in motor commands are made to accommodate changes in muscle load, maintain an upright posture, and anticipate and avoid errors. Brainstem motor control centers employ circuits in lower parts of the motor hierarchy to produce fairly complex movements, such as ingestion or locomotion. Since the brain adds meaning to movements, two different actions can share the same component movements and serve different end goals. Brain lesions may independently impair movements made under different contexts. For example, patients may be unable to smile volitionally while retaining the ability to smile in response to a joke.

scholarly journals Value of neuroimaging in epilepsy: An experience from Pakistan

2013 ◽  
Vol 04 (S 01) ◽  
pp. S35-S39 ◽  
Author(s):  
Ahmed Bakhsh
Keyword(s):  
Prospective Study ◽  
Neurological Deficit ◽  
Outpatient Setting ◽  
Brain Lesions ◽  
Idiopathic Epilepsy ◽  
Mri Scan ◽  
Epileptic Patients ◽  
The Brain ◽  
Underlying Pathology ◽  
Structural Brain

ABSTRACT Purpose: To detect the possible structural brain lesions in the patients suffering from various kinds of epilepsy during the routine neuroimaging. Materials and Methods: Prospective study of 366 epileptic patients conducted at epilepsy clinic, Rawalpindi-Islamabad Pakistan in an outpatient setting. MRI or CT scan of the brain without contrast was advised in all patients to detect any underlying pathology. Results: A total 21.31% scans were found to be abnormal. Many cases of familial, idiopathic epilepsy and patients without any neurological deficit were found to have structural brain lesions, which might be responsible for their seizures. Conclusion: CT/MRI scan of the brain should be advised in all patients of epilepsy regardless of cause and type of epilepsy. The presence of neurological deficit should not be the sole indication for neuroimaging.

scholarly journals Acute Psychosis Associated with Subcortical Stroke: Comparison between Basal Ganglia and Mid-Brain Lesions

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Aaron McMurtray ◽  
Ben Tseng ◽  
Natalie Diaz ◽  
Julia Chung ◽  
Bijal Mehta ◽  
...  
Keyword(s):  
Basal Ganglia ◽  
Psychiatric Symptoms ◽  
Symptomatic Relief ◽  
Acute Onset ◽  
Brain Lesions ◽  
Psychotic Symptoms ◽  
History Of ◽  
The Brain ◽  
Brain Ischemic Stroke ◽  
New Onset

Acute onset of psychosis in an older or elderly individual without history of previous psychiatric disorders should prompt a thorough workup for neurologic causes of psychiatric symptoms. This report compares and contrasts clinical features of new onset of psychotic symptoms between two patients, one with an acute basal ganglia hemorrhagic stroke and another with an acute mid-brain ischemic stroke. Delusions and hallucinations due to basal ganglia lesions are theorized to develop as a result of frontal lobe dysfunction causing impairment of reality checking pathways in the brain, while visual hallucinations due to mid-brain lesions are theorized to develop due to dysregulation of inhibitory control of the ponto-geniculate-occipital system. Psychotic symptoms occurring due to stroke demonstrate varied clinical characteristics that depend on the location of the stroke within the brain. Treatment with antipsychotic medications may provide symptomatic relief.

“Miliary” metastatic tumors in the brain

1997 ◽  
Vol 86 (3) ◽  
pp. 564-566 ◽  
Author(s):  
Chhabi Bhushan
Keyword(s):  
Basal Ganglia ◽  
Primary Tumor ◽  
Metastatic Tumor ◽  
Mass Effect ◽  
Brain Lesions ◽  
Metastatic Tumors ◽  
Content Type ◽  
Brain Parenchymal ◽  
The Brain ◽  
Fine Print

✓ An extremely unusual “miliary” metastatic tumor of the brain in a 69-year-old man is reported. Although there was no known primary tumor, the patient had innumerable brain lesions involving both cerebral and both cerebellar hemispheres, the basal ganglia, and the brainstem. There was no associated edema, mass effect, or brain parenchymal reaction. None of the lesions showed any calcification.

scholarly journals Severe acute respiratory syndrome coronavirus 2 and seizure: An insight into the pathophysiologic mechanisms

2021 ◽  
Author(s):  
Shima Zareh-Shahamati ◽  
Mahyar Noorbakhsh ◽  
Hadi Digaleh ◽  
Behnam Safarpour-Lima ◽  
Behnam Safarpour-Lima
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Brain Lesions ◽  
The Other ◽  
Cytokine Storm ◽  
Hematogenous Spread ◽  
Metabolic Derangement ◽  
Underlying Mechanisms ◽  
Insight Into ◽  
Structural Brain ◽  
Pathophysiologic Mechanisms

Based on previous studies, seizure has been reported to accompany coronavirus disease 2019 (COVID-19). Underlying mechanisms are those leading to the direct central nervous system (CNS) invasion through hematogenous spread or trans-synaptic retrograde invasion, causing meningoencephalitis. On the other hand, there are pathophysiologic mechanisms that seizure would be one of their early consequences, such as cytokine storm, hypoxemia, metabolic derangement, and structural brain lesions. Herein, we focused on available evidence to provide an insight into the pathophysiologic mechanisms that link seizure and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, as a better understanding of pathophysiology would lead to better diagnosis and treatment.

scholarly journals Stereotactic Radiosurgery in the Complex Treatment of Patients With Epilepsy Associated With Various Structural Brain Lesions

2021 ◽  
Vol 10 (1) ◽  
pp. 73-82
Author(s):  
V. V. Krylov ◽  
V. A. Rak ◽  
A. S. Tokarev ◽  
M. V. Sinkin ◽  
I. S. Trifonov ◽  
...  
Keyword(s):  
Stereotactic Radiosurgery ◽  
Hippocampal Sclerosis ◽  
Brain Lesions ◽  
Class I ◽  
Complex Treatment ◽  
Symptomatic Epilepsy ◽  
Patients With Epilepsy ◽  
The Brain ◽  
Structural Brain ◽  
Observation Period

BACKGROUND Structural damage to the brain substance in adults is one of the most common causes of epilepsy. Currently, such patients are prescribed drug therapy and/or surgery. With this approach, epileptic symptoms can persist in a significant proportion of patients (up to 30%, depending on the disease).AIM OF STUDY To clarify the efficacy of stereotactic radiosurgery (STS) as part of the complex treatment of patients suffering from pharmacoresistant symptomatic epilepsy with hippocampal sclerosis, vascular malformations, and some benign tumors of the brain and its membranes.MATERIAl AND METHODS Examination and radiosurgical treatment were carried out in 45 patients with various brain diseases accompanied by symptomatic epilepsy, provided that the previous conservative or surgical treatment was insufficiently effective. During the observation period, the frequency of seizures was assessed and the presence and nature of postoperative complications were recorded.RESUlTS With a median follow-up of 30 months, good outcomes (class I–II according to J. Engel’s scale) were observed in 5 out of 8 patients with hippocampal sclerosis who underwent STS after  amygdaloghippocamplobectomy; seizure frequency decreased in all patients. Complications of STS were noted in 2 patients and had a transient nature. In the group of patients with meningiomas, in 4 out of 8 patients, seizures completely stopped, in 3 patients the frequency of seizures decreased by more than 90%, in another 1 the frequency of seizures decreased by 60%. There were no complications of STS during the observation period. Inintracerebral tumors (diffuse astrocytoma), Engel Ia outcome was observed in both patients. In the group of patients with cavernous angiomas, there were good outcomes (class I–II according to J. Engel’s scale) in 17 patients (85%). Deterioration (Engel IVc outcome) was observed in 1 patient (5%), 2 patients (10%) had complications of STS. In the group of patients with arteriovenous malformations, good outcomes (classes I–II according to J. Engel’s scale) were found in all 7 patients. The complication after STS was revealed in 1 patient.CONClUSION The presented results confirm the high efficiency and low risk of side effects when using stereotactic radiosurgery in the complex treatment of patients with epilepsy associated with common structural brain lesions.

scholarly journals Basal Ganglia Herniation into the Fourth Ventricle

1997 ◽  
Vol 24 (1) ◽  
pp. 62-63 ◽  
Author(s):  
Mensura Altumbabic ◽  
Marc R. Del Bigio ◽  
Scott Sutherland
Keyword(s):  
Basal Ganglia ◽  
Intracerebral Hemorrhage ◽  
Fourth Ventricle ◽  
Transtentorial Herniation ◽  
Intracerebral Bleeding ◽  
Rare Phenomenon ◽  
The Brain

ABSTRACT:Background:Transtentorial herniation of large cerebral fragments is a rare phenomenon.Method:Case StudyResults:Examination of the brain of a 35-year-old male showed massive intracerebral hemorrhage resulting in displacement of basal ganglia components into the fourth ventricle.Conclusions:Sufficiently rapid intracerebral bleeding can dissect fragments of cerebrum and displace them long distances across the tentorial opening.

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