Separate Memory-Enhancing Effects of Reward and Strategic Encoding

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neuroimaging

Background:

• Memory encoding for important information is enhanced by reward anticipation and intentional strategies.
• These effects are hypothesized to depend on distinct neural mechanisms, but evidence for separability is limited.

Purpose of the Study:

• To determine if reward-driven and strategic mechanisms for prioritizing important information are separable.
• To examine the joint operation of these mechanisms using functional magnetic resonance imaging (fMRI).

Main Methods:

• Participants learned abstract visual images in a value-directed recognition paradigm.
• fMRI measured brain activity during encoding of high-value and low-value images.
• Psychophysiological interaction analysis assessed functional connectivity.

Main Results:

• Successful memory encoding, especially for high-value images, showed increased activity in dorsal frontoparietal and lateral occipitotemporal cortex.
• Reward-related network activity was higher during encoding for subsequently remembered images (regardless of value).
• Strategic prioritization of high-value images modulated activity in dorsal posterior parietal cortex and its connectivity with lateral temporal cortex.

Conclusions:

• Memory strengthening involves separate neurocognitive mechanisms for strategic control and reward-based enhancement.
• Distinct brain regions and functional connectivity patterns support these separable memory processes.