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Neuroscience and Biobehavioral Reviews May 2020Akinetic mutism (AM) is a rare neurological disorder characterized by the presence of an intact level of consciousness and sensorimotor capacity, but with a simultaneous... (Review)
Review
Akinetic mutism (AM) is a rare neurological disorder characterized by the presence of an intact level of consciousness and sensorimotor capacity, but with a simultaneous decrease in goal-directed behavior and emotions. Patients are in a wakeful state of profound apathy, seemingly indifferent to pain, thirst, or hunger. It represents the far end within the spectrum of disorders of diminished motivation. In recent years, more has become known about the functional roles of neurocircuits and neurotransmitters associated with human motivational behavior. More specific, there is an increasing body of behavioral evidence that links specific damage of functional frontal-subcortical organization to the occurrence of distinct neurological deficits. In this review, we combine evidence from lesion studies and neurophysiological evidence in animals, imaging studies in humans, and clinical investigations in patients with AM to form an integrative theory of its pathophysiology. Moreover, the specific pharmacological interventions that have been used to treat AM and their rationales are reviewed, providing a comprehensive overview for use in clinical practice.
Topics: Adrenergic Uptake Inhibitors; Akinetic Mutism; Animals; Dopamine Agonists; Dopamine Uptake Inhibitors; Dopaminergic Neurons; GABA-A Receptor Agonists; Gray Matter; Humans; Motivation; Zolpidem
PubMed: 32044373
DOI: 10.1016/j.neubiorev.2020.02.006 -
Cureus Jan 2021Pediatric akinetic mutism syndrome is a clinical disease resulting from cerebellar injury and characterized by the absence of speech or reduced speech, emotional... (Review)
Review
Pediatric akinetic mutism syndrome is a clinical disease resulting from cerebellar injury and characterized by the absence of speech or reduced speech, emotional lability, there may also be hypotonia, oropharyngeal dysfunction/dysphagia, bladder and intestinal incontinence, or other behavioral disorders and neurological signals. It is described as the most recurrent complication in children, after posterior fossa tumor surgery, mainly related to cerebellar midline injuries. An increasing number of research and prospective reviews have provided valuable information on cerebellar mutism syndrome in recent years. The purpose of this review was to elucidate the pathophysiological basis and the predictive factors for this syndrome. Most cases of mutism are due to injury cerebellar tracts and cerebellar-cerebral circuits, involving particularly distinct points of the dentate-thalamus-cortical and dentato-rubro-thalamus-cortical. Advanced neuroimaging techniques, such as tractography and perfusion studies, have contributed to demonstrating changes in these pathways in patients with pediatric cerebellar mutism.
PubMed: 33542880
DOI: 10.7759/cureus.12593 -
Journal of the Academy of... 2021Coronavirus disease 2019 (COVID-19) has been associated with neuropsychiatric complications ranging from new-onset psychosis to delirium, dysexecutive syndromes,... (Review)
Review
BACKGROUND
Coronavirus disease 2019 (COVID-19) has been associated with neuropsychiatric complications ranging from new-onset psychosis to delirium, dysexecutive syndromes, catatonia, and akinetic mutism (AM). AM can be conceptualized as a disorder of motivation wherein patients exhibit a loss of speech and spontaneous movement, owing to disruption of underlying frontal-subcortical circuits.
OBJECTIVES
The objectives of this study were to review the concept and differential diagnosis of AM, as well as the clinical literature on AM in COVID-19 and discuss potential implications for underlying functional neuroanatomy and mechanistic pathways, as well as clinical management.
METHODS
A narrative literature review was performed using PubMed querying published articles for topics associated with AM and its occurrence in COVID-19.
RESULTS
AM has been described in case reports and a prospective cohort study of patients with COVID with neurological complaints. Three COVID-19 AM subgroups can be distinguished, including individuals with severe respiratory illness, those with meningoencephalitis, and those with delirium and pre-existing neuropsychiatric illness. Electrophysiology and functional imaging suggest COVID-19 AM may result from underlying frontal lobe dysfunction and disruption of associated distributed circuits subserving goal-directed behavior. Distinctive combinations of pathophysiological mechanisms may be at play in the different subgroups of COVID-19 AM cases.
CONCLUSION
AM has been described in association with COVID-19 and may manifest in clinically heterogenous subgroups with distinct underlying mechanisms. The diagnosis of AM and evaluation of potential etiologies can be complex. The occurrence of AM contributes evidence to the hypothesis of frontal lobe dysfunction in COVID-19.
Topics: Akinetic Mutism; COVID-19; Humans; Motivation; Prospective Studies; SARS-CoV-2
PubMed: 34461295
DOI: 10.1016/j.jaclp.2021.08.009 -
Neurology Mar 1958
Topics: Akinetic Mutism; Humans; Medical Records; Movement Disorders; Speech Disorders
PubMed: 13517492
DOI: 10.1212/wnl.8.3.238 -
Fortschritte Der Neurologie-Psychiatrie Feb 1995Cairns and coworkers (1941) introduced the term "akinetic mutism" to denote a syndrome characterised by lack of responsiveness in the presence of apparently preserved... (Review)
Review
Cairns and coworkers (1941) introduced the term "akinetic mutism" to denote a syndrome characterised by lack of responsiveness in the presence of apparently preserved vigilance. The present paper reviews clinical data as well as results of animal experimentation to outline the functional-neuroanatomic basis of this constellation. The clinical literature following the original publication of Cairns et al. (1941) reported syndromes of "akinetic mutism" in bilateral mesodiencephalic or frontal lesions of various aetiology. At least two pathomechanisms of akinetic mutism can be differentiated: (a) reduced "arousal" of cortical functions due to lesions at or rostral to the mesodiencephalic junction; (b) impaired activation of the motor system following bilateral damage to the frontal lobes. Since perceptual and cognitive functions are disturbed as well in mesodiencephalic akinetic mutism, the latter notion does not seem to be adequate. The terms "apallic syndrome" or "vegetative state" are rather more appropriate in these instances. The label "akinetic mutism" can then be restricted to a pathophysiologically distinct syndrome, i.e. reduced motor activation following bilateral frontal damage.
Topics: Akinetic Mutism; Animals; Arousal; Attention; Brain Damage, Chronic; Brain Mapping; Diencephalon; Frontal Lobe; Humans; Mesencephalon; Motivation
PubMed: 7705740
DOI: 10.1055/s-2007-996603 -
Age and Ageing May 2009We describe a case of akinetic mutism mistaken as coma. A 77-year old lady presented with apparent unresponsiveness. In fact she responded when stimulated. She...
We describe a case of akinetic mutism mistaken as coma. A 77-year old lady presented with apparent unresponsiveness. In fact she responded when stimulated. She subsequently developed movements typical of clonic perseveration, erroneously treated as seizures. She also had features of a frontal lobe syndrome. Initial CT scan showed no abnormality; it was only after an MRI scan that a diagnosis of bilateral paramedian thalamic infarction was made. MRI scanning should be considered early in the investigation of patients with atypical neurological presentation.
Topics: Aged; Akinetic Mutism; Anticonvulsants; Cerebral Infarction; Coma; Diagnostic Errors; Humans; Magnetic Resonance Imaging; Male; Movement; Neurologic Examination; Seizures; Sensation; Thalamus
PubMed: 19297375
DOI: 10.1093/ageing/afp005 -
Neuropsychiatry, Neuropsychology, and... Oct 1997Akinetic mutism may result from anterior cingulate lesions or a disconnection of the limbic connections projecting from the cingulate through subcortical circuits. Based... (Review)
Review
Akinetic mutism may result from anterior cingulate lesions or a disconnection of the limbic connections projecting from the cingulate through subcortical circuits. Based on nonhuman primate primate tracer studies, ventral pallidal lesions should disrupt the anterior cingulate frontal-subcortical circuit. A patient developed a rigid akinetic mute state caused by bilateral lesions of the globus pallidus interna with ventral extension. The anatomic basis of the patient's clinical findings support a similarity in frontal-subcortical anatomy between humans and nonhuman primates. Isolated pallidal lesions are rare. Future studies should document whether ventral extension below the anterior commissure is associated with a loss of motivation.
Topics: Aged; Akinetic Mutism; Aphasia; Atrophy; Female; Frontal Lobe; Globus Pallidus; Humans; Magnetic Resonance Imaging; Motivation; Neural Pathways; Neuropsychological Tests
PubMed: 9359123
DOI: No ID Found -
Medical Science Monitor : International... Feb 2022Akinetic mutism (AM) is characterized by the complete absence of spontaneous behavior (akinesia) and speech (mutism) with the preservation of executive functions for... (Review)
Review
A Review of Studies on the Role of Diffusion Tensor Magnetic Resonance Imaging Tractography in the Evaluation of the Fronto-Subcortical Circuit in Patients with Akinetic Mutism.
Akinetic mutism (AM) is characterized by the complete absence of spontaneous behavior (akinesia) and speech (mutism) with the preservation of executive functions for movements and speaking. Elucidation of the pathophysiological mechanisms or neural correlates for AM is clinically important because patients can recover from AM after medication and neuromodulation. The fronto-subcortical circuit is a critically important neural structure in the pathophysiology of AM. Using diffusion tensor tractography, a few neural tracts in the fronto-subcortical circuit can be reconstructed. This mini-review article evaluated 6 DTT-based studies on the fronto-subcortical circuit injury in patients with AM. According to these results, the neural tracts among the fronto-subcortical circuit, which are related to AM, were as follows (in decreasing order of importance): 1) the prefronto-caudate tract, 2) the prefronto-thalamic tract, and 3) the cingulum. In particular, the medial prefrontal cortex is an important brain area related to recovery from AM. However, only 6 studies on this topic have been published, and most were case reports. In addition, these studies analyzed only a few neural tracts in the fronto-subcortical circuit. Because AM is a rare disorder, studies involving a large number of subjects might be impossible. Nevertheless, an analysis of various neural tracts in the fronto-subcortical circuit is necessary. For this, reconstruction of the other neural tracts in the fronto-subcortical circuit should be performed first. This review aims to present the findings from recent studies on the role of DTT in evaluation of fronto-subcortical circuit injury in patients with AK.
Topics: Akinetic Mutism; Diffusion Magnetic Resonance Imaging; Diffusion Tensor Imaging; Humans; Neural Pathways; Prefrontal Cortex
PubMed: 35181647
DOI: 10.12659/MSM.936251 -
Neurological Sciences : Official... Aug 2023
Topics: Humans; Tacrolimus; Akinetic Mutism; Dysarthria; Liver Transplantation; Immunosuppressive Agents
PubMed: 36949300
DOI: 10.1007/s10072-023-06760-6 -
Journal of Neurological Surgery. Part... Sep 2012
Review
Topics: Akinetic Mutism; Antiparkinson Agents; Bromocriptine; Child; Female; Humans; Hydrocephalus; Parkinson Disease; Physical Therapy Modalities; Treatment Outcome; Ventriculoperitoneal Shunt
PubMed: 21445822
DOI: 10.1055/s-0032-1313632