Identifying Feigned Cognitive Impairment: Investigating the Utility of Diffusion Model Analyses

Area of Science:

• Cognitive Psychology
• Neuropsychology
• Forensic Psychology

Background:

• Forced-choice performance validity tests are crucial for detecting feigned cognitive impairment.
• The drift diffusion model analyzes speed-accuracy trade-offs to understand cognitive processes.
• No prior research has applied the drift diffusion model to a well-established forced-choice performance validity test.

Purpose of the Study:

• To investigate the utility of the drift diffusion model in differentiating between genuine and simulated cognitive impairment.
• To analyze cognitive processes underlying performance on the Word Memory Test using the EZ-diffusion model.

Main Methods:

• Archival data from 198 healthy participants were analyzed.
• Participants either simulated cognitive impairment or performed the Word Memory Test optimally.
• The EZ-diffusion model was used to assess drift diffusion model parameters.

Main Results:

• Significant differences were observed in all three drift diffusion model parameters between the groups.
• Drift rate emerged as the most effective parameter in predicting group membership.
• This indicates distinct cognitive processes between genuine and feigned impairment.

Conclusions:

• The drift diffusion model offers valuable insights into the cognitive mechanisms of feigned cognitive impairment.
• Drift rate is a promising indicator for detecting malingering in performance validity testing.
• Further research is warranted to validate and expand upon these findings.