A circular diffusion model of continuous-outcome source memory retrieval: Contrasting continuous and threshold...

Area of Science:

• Cognitive Psychology
• Computational Neuroscience
• Memory Research

Background:

• Existing models of source retrieval often attribute response variability solely to memory processes.
• The circular diffusion model offers a novel approach by decomposing noise into memory and decision-related variability.
• Continuous response tasks in memory research require sophisticated modeling techniques.

Purpose of the Study:

• To apply a circular diffusion model to a continuous-outcome source memory task.
• To compare the fits of three distinct diffusion models to empirical data.
• To investigate the underlying mechanisms of source memory retrieval in continuous tasks.

Main Methods:

• Utilized a circular analogue of the diffusion model for continuous response tasks.
• Compared three diffusion models: single process with variable drift, mixture of processes with discrete guessing, and a hybrid model.
• Analyzed joint response error and response-time (RT) data.
• Conditioned source responding on confidence ratings from an old/new recognition task.

Main Results:

• Model fits suggest a memory strength threshold below which no information is retrieved in continuous-report source memory tasks.
• Findings indicate that guessing is not solely due to unrecognized items.
• The results challenge the assumptions of purely continuous models of source memory.

Conclusions:

• Source memory retrieval appears to operate under an all-or-none or some-or-none principle.
• A memory strength threshold is a critical factor in continuous source memory tasks.
• The findings necessitate a re-evaluation of continuous models in favor of threshold-based accounts.