MemTrax

MemTrax measures episodic memory performance using a continuous recognition task (CRT) to provide quantitative metrics of accuracy and response time.

Key Features:

• Continuous Recognition Task (CRT): Implementation of a CRT that records stimulus responses to assess episodic memory.
• Data Collection and Analysis: Records correct responses (HITs), Correct Rejections, and response times (RTs) measured to the thousandth of a second for population-level analysis.
• Performance Metrics: Analysis of 322,996 valid first tests reported that 63% of participants achieved at least 45 correct responses (90%), 92% scored ≥40 correct (80%), and 3% scored ≤35 correct (70%).
• Response Time Analysis: RT distribution is skewed with 1% of responses faster than 0.62 seconds, 1% slower than 1.57 seconds, a median RT of 0.890 seconds, and is modeled by the reverse-exponential (RevEx) function.
• Correlation Between Speed and Accuracy: Analysis found a positive correlation between faster RTs and higher HIT accuracy.

Scientific Applications:

• Clinical Diagnosis: Provides quantitative metrics to aid assessment of memory dysfunctions.
• Monitoring Progression: Enables longitudinal tracking of episodic memory performance for evaluating disease progression or treatment effects.
• Research Studies: Supports population-level and individual-level studies of episodic memory performance and its distributions.

Methodology:

Uses a continuous recognition task (CRT) to record HITs, Correct Rejections, and response times (RTs) measured to the thousandth of a second; performs statistical analysis of correctness and RT distributions across 322,996 valid first tests; models RT distribution with the reverse-exponential (RevEx) function and assesses correlation between RT speed and HIT accuracy.