Episodic memory and learning rates in amyotrophic lateral sclerosis without dementia

Area of Science:

• Neuroscience
• Cognitive Neurology

Background:

• Amyotrophic lateral sclerosis (ALS) is associated with cognitive impairments, including memory deficits.
• These memory deficits can be primary or secondary to executive dysfunction.

Purpose of the Study:

• To assess and compare episodic memory and executive function in non-demented ALS patients.
• To compare episodic memory profiles and learning rates of ALS patients with mild cognitive impairment (MCI) and healthy controls (HC).

Main Methods:

• 72 non-demented ALS patients, 57 amnestic MCI (aMCI), 89 dysexecutive MCI, and 190 HC were enrolled.
• Screening included the Frontal Assessment Battery and Mini Mental State Examination.
• Episodic memory and learning rates were evaluated using the Rey Auditory Verbal Learning Test (RAVLT).

Main Results:

• 19.4% of ALS patients exhibited episodic memory dysfunction (immediate recall).
• ALS patients performed worse than HC on immediate recall but had similar learning rates.
• ALS patients outperformed aMCI subjects on all RAVLT measures and showed better verbal learning than dysexecutive MCI subjects.

Conclusions:

• Episodic memory performance in ALS patients is better than in aMCI but comparable to dysexecutive MCI.
• Executive dysfunction in ALS patients is associated with poorer episodic memory recall and learning.
• Findings suggest that episodic memory impairment in ALS may be partly secondary to executive dysfunction.