Related Experiment Video
Updated: Jul 7, 2026
05:39
A Fine Motor Task to Study Joint Kinematics in a Preclinical Model of Neurodegenerative Disease
Published on: June 13, 2025
Coupling and irregularity in the aging motor system: tremor and movement
S Lee Hong1, Eric G James, Karl M Newell
1Department of Kinesiology, Louisiana State University, 112 H.P. Long Fieldhouse, Baton Rouge, LA 70803, United States. shongl@lsu.edu
Neuroscience Letters
|February 12, 2008
Summary
Aging reduces motor control complexity, impacting movement and balance. This study found older adults exhibit less complex motor behavior, particularly in postural control, suggesting reduced adaptability.
Area of Science:
- Motor control and aging research
- Human movement science
- Neuroscience of aging
Background:
- Aging is associated with changes in motor control and behavior.
- Reduced complexity in behavior has been hypothesized to be a consequence of aging.
- Understanding these changes is crucial for maintaining function in older adults.
Purpose of the Study:
- To investigate the hypothesis that aging reduces the coupling between system components, leading to a loss of behavioral complexity.
- To examine age-related differences in motor control during rhythmical movement and postural tasks.
- To determine if motor adaptability is reduced in older adults.
Main Methods:
- Recruitment of young (18-23 years), old (60-65 years), and older old (70-75 years) subjects.
- Performance of rhythmical movement and postural tasks using the index finger.
- Analysis of acceleration dynamics and coupling across axes of motion.
Main Results:
- Lower irregularity of acceleration dynamics was observed in older adults during postural tremor and movement, specifically on the mediolateral axis.
- Increased coupling across axes of motion was found in elderly subjects during rhythmic movement.
- The loss of complexity with aging was detectable in healthy 60-65-year-olds.
Conclusions:
- Aging leads to a loss of complexity in motor behavior, detectable even in healthy older adults.
- Postural tremor analysis requires examination across multiple axes of motion.
- Reduced motor adaptability in aging may stem from increased demands on task-related motor output reorganization.
Related Concept Videos
01:11Alterations in Muscle Tone lll
Rigidity and myotonia are distinct abnormalities of muscle tone that affect resistance and relaxation during movement. Although both involve altered muscle contraction, they arise from different neurological and muscular mechanisms.CharacteristicsRigidity is characterized by uniform resistance to passive movement across the entire range, independent of speed, affecting flexors and extensors equally. It may appear as lead-pipe rigidity (smooth, constant resistance) or cogwheel rigidity...
01:12Alterations in Muscle Tone ll
Alterations in muscle tone are common manifestations of neurological disorders and reflect dysfunction within different nervous system regions. Spasticity, paratonia, and dystonia represent distinct forms of hypertonia, each with unique mechanisms, clinical features, and diagnostic importance.CharacteristicsSpasticity happens from upper motor neuron lesions and is characterized by velocity-dependent resistance to passive movement. Clinical features include:Exaggerated deep tendon reflexesClonus...
01:24Parkinson Disease ll: Pathophysiology
Parkinson disease (PD) is a progressive neurodegenerative disorder primarily affecting movement, with additional non-motor features. Its pathophysiology involves complex interactions among genetic susceptibility, environmental exposures, and cellular dysfunction, including dopaminergic neuron loss, protein aggregation, and mitochondrial impairment.Selective NeurodegenerationA key feature is the degeneration of dopaminergic neurons in the substantia nigra pars compacta, leading to reduced...
01:24Parkinson Disease l: Introduction
Parkinson’s disease is a chronic, progressive neurodegenerative disorder that primarily affects movement. It is characterized by motor symptoms such as resting tremors, muscle rigidity, bradykinesia (slowness of movement), and postural instability. Patients may notice hand tremors at rest, stiffness during movement, or a shuffling gait. In addition to motor features, non-motor symptoms include sleep disturbances, mood and behavioral changes, constipation, and cognitive impairment, all of which...
01:15Parkinson's Disease: Overview
Neurodegenerative disorders are progressive diseases that cause irreversible damage and loss to neurons in specific brain areas. Examples of these disorders include Parkinson's disease, Alzheimer's disease, Multiple Sclerosis (MS), and Amyotrophic Lateral Sclerosis (ALS). These disorders share characteristics such as proteinopathies, selective neuronal vulnerability, and a complex interplay between genetic and environmental factors. The primary therapeutic goal for these conditions is to...
01:24Parkinson's Disease: Treatment
Neurodegenerative disorders, such as Parkinson's Disease (PD), involve the gradual and irreversible destruction of neurons in particular brain areas. These disorders exhibit standard features like proteinopathies, selective vulnerability of some neurons, and an interaction of intrinsic properties, genetics, and environmental influences in neural injury.
Parkinson's Disease is primarily a result of the loss of dopaminergic neurons in the substantia nigra pars compacta. The cornerstone of its...
Parkinson's Disease is primarily a result of the loss of dopaminergic neurons in the substantia nigra pars compacta. The cornerstone of its...