Related Experiment Video
Updated: Jul 17, 2026
08:16
Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis
Published on: March 4, 2014
Asymmetrical alien hands in corticobasal degeneration
David B Fitzgerald1, Valeria Drago, Yong Jeong
1Department of Neurology, University of Florida, Gainesville, Florida, USA. dfitzger@massmed.org
Summary
Alien limb in corticobasal degeneration presents uniquely. A patient showed distinct right-hand avoidance and left-hand pursuit behaviors, suggesting complex neurological underpinnings.
Area of Science:
- Neuroscience
- Neurology
- Clinical Neurophysiology
Background:
- Corticobasal degeneration (CBD) is a rare neurodegenerative disorder.
- Alien limb phenomenon (ALP) is a complex neurological disorder.
- Understanding ALP in CBD is crucial for diagnosis and management.
Observation:
- A patient with corticobasal degeneration exhibited two distinct forms of alien limb phenomenon.
- The right hand displayed a tactile avoidance response with levitation.
- The left hand demonstrated continuous tactile pursuit, known as tactile mitgehen.
Findings:
- The patient's alien limb presentation involved both avoidance and pursuit behaviors.
- Tactile mitgehen is typically linked to frontal lobe dysfunction.
- Avoidance response and levitation are often associated with parietal lobe dysfunction.
Implications:
- This case highlights the diverse manifestations of alien limb in corticobasal degeneration.
- The findings suggest a complex interplay of frontal and parietal lobe dysfunction in CBD-related ALP.
- Further research is needed to fully understand the neuroanatomical correlates of these distinct alien limb presentations.
More Related Videos
Related Concept Videos
01:33Somatosensation
The somatosensory system relays sensory information from the skin, mucous membranes, limbs, and joints. Somatosensation is more familiarly known as the sense of touch. A typical somatosensory pathway includes three types of long neurons: primary, secondary, and tertiary. Primary neurons have cell bodies located near the spinal cord in groups of neurons called dorsal root ganglia. The sensory neurons of ganglia innervate designated areas of skin called dermatomes.
01:24Prosopagnosia
Prosopagnosia, also known as face blindness, is the inability to recognize faces. In severe cases, individuals with prosopagnosia may not recognize close family members, including parents and spouses, by their faces. For instance, someone with prosopagnosia might walk past their child in a crowd, only realizing their mistake upon noticing their child's distinctive backpack or favorite jacket. Prosopagnosia specifically impairs facial recognition, while the recognition of other objects or...
01:21Huntington Disease l: Introduction
Huntington disease or HD is a progressive, fatal neurodegenerative disorder inherited in an autosomal dominant pattern.PathophysiologyIt is caused by expansion of the CAG trinucleotide repeat in the HTT gene on chromosome 4 (4p16.3), producing an abnormal huntingtin protein with an expanded polyglutamine tract. This misfolded protein disrupts cellular function, leading to neuronal death. Normal alleles have ≤26 repeats, 27–35 are intermediate (risk of expansion), 36–39 show reduced penetrance,...
01:16Muscles of the Forearm that Move the Hand and Fingers
The muscles of the forearm that move the wrist, hand, and digits are numerous and diverse. They can be classified into two groups based on their location and function — the anterior and posterior compartment muscles.
Anterior Compartment
The anterior compartment muscles originate from the humerus. They primarily function as flexors and are also known as flexor muscles. They typically insert on the carpals, metacarpals, and phalanges. The superficial layer includes the flexor carpi radialis,...
Anterior Compartment
The anterior compartment muscles originate from the humerus. They primarily function as flexors and are also known as flexor muscles. They typically insert on the carpals, metacarpals, and phalanges. The superficial layer includes the flexor carpi radialis,...
01:12Visual Agnosia
Visual agnosia is a condition characterized by the inability to recognize visually presented objects despite having normal vision. For instance, a person with visual agnosia can describe the shape and color of an object but cannot identify or name it. This impairment does not affect their visual field, acuity, color vision, brightness discrimination, language, or memory. An example of this condition in a social setting is someone at a dinner party asking for "that silver thing with a round end"...
01:28Lateralization
Brain lateralization refers to the division of mental processes and functions between the two hemispheres of the brain, a phenomenon that optimizes neural efficiency and underpins complex abilities in humans. This specialization allows each hemisphere to perform tasks where it has a comparative advantage, facilitating more refined cognitive capabilities across different domains.