Mental imagery and perception overlap within transmodal association networks

Area of Science:

• Cognitive Neuroscience
• Neuroimaging

Background:

• Human cognition operates in perceptually coupled (sensory-driven) and perceptually decoupled (self-generated) modes.
• Mental imagery, crucial for decoupled cognition, is traditionally linked to sensory cortex reinstatement, but transmodal systems also play a role in related processes like future thinking and mind-wandering.

Purpose of the Study:

• To investigate the neural underpinnings of self-generated mental states, specifically mental imagery, during perceptually decoupled cognition.
• To differentiate the roles of unimodal sensory networks versus transmodal association networks in supporting different types of mental imagery.

Main Methods:

• Utilized precision functional Magnetic Resonance Imaging (fMRI) to capture brain activity during imagined scenarios.
• Employed multi-dimensional experience sampling to allow participants to rate their subjective mental states post-imaging.

Main Results:

• Imagining scenes activated the default network, while imagining speech engaged the language network.
• Overlap between imagined and perceived/heard content was found primarily within transmodal association networks, not adjacent unimodal sensory networks.

Conclusions:

• Transmodal networks are critical for supporting self-generated mental states, including various forms of mental imagery.
• This challenges the view that mental imagery relies solely on sensory cortex reinstatement, highlighting the importance of higher-order association areas.