Perception and memory retrieval states are reflected in distributed patterns of background functional connectivity.

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Functional Neuroimaging

Background:

• Visual input can be processed for perception (external focus) or memory retrieval (internal focus).
• Previous studies focused on stimulus-evoked activity, overlooking intrinsic neural states.
• Distinct background functional connectivity may underlie perception and memory retrieval.

Purpose of the Study:

• To investigate differences in "background" functional connectivity between perception and memory retrieval states.
• To determine if these background connectivity patterns are independent of stimulus-evoked neural activity.
• To identify specific brain networks involved in differentiating cognitive states.

Main Methods:

• Utilized human functional magnetic resonance imaging (fMRI).
• Employed full correlation matrix analysis (FCMA) to assess functional connectivity.
• Analyzed connectivity patterns within and between large-scale brain networks, including the control network, default mode network (DMN), and retrosplenial cortex (RSC).

Main Results:

• Perception and retrieval states were accurately discriminated by connectivity patterns.
• The control network showed increased intra-network connectivity during perception.
• The default mode network (DMN) exhibited stronger coupling during memory retrieval.
• Retrosplenial cortex (RSC) dynamically altered its network coupling based on cognitive state.
• Background connectivity was independent of stimulus-related neural activity.

Conclusions:

• Perception and memory retrieval are associated with distinct, sustained cognitive states.
• These cognitive states manifest as unique patterns of large-scale brain network connectivity.
• Background functional connectivity provides insights into cognitive states beyond stimulus-evoked responses.