Markers for upper limb dysfunction in Amyotrophic Lateral Sclerosis using analysis of typing activity

Area of Science:

• Neurology
• Biomedical Engineering
• Rehabilitation Science

Background:

• Keyboard access via assistive devices is crucial for communication and control in patients with Amyotrophic Lateral Sclerosis (ALS).
• Understanding upper limb (UL) function is vital for managing ALS progression and maintaining patient independence.
• Objective markers are needed to continuously monitor functional decline in ALS patients.

Purpose of the Study:

• To investigate movement activity during keyboard use in ALS patients.
• To identify specific markers of upper limb (UL) dysfunction related to typing.
• To explore the potential of typing activity analysis for remote monitoring of ALS progression.

Main Methods:

• A longitudinal study tracked 19 ALS patients over 2-20 months, with 2-6 typing assessments per patient.
• An accelerometer on the index finger recorded typing activity, focusing on time and acceleration during keystrokes.
• ALS patients were compared to healthy subjects and patients with other neuromuscular disorders.

Main Results:

• Increased time holding down keys and prolonged delay between tapping and pressing keys were observed with disease progression.
• Decreased acceleration during key press and release correlated with worsening UL dysfunction.
• Typing metrics showed significant differences between ALS patients and control groups.

Conclusions:

• Key press/release delays and reduced keystroke acceleration serve as reliable markers for UL dysfunction in ALS.
• Typing activity analysis offers a non-invasive, remote method for continuous monitoring of ALS progression.
• These findings can inform the development of better assistive technologies and rehabilitation strategies for ALS.