Attention control processes that prioritise task execution may come at the expense of incidental memory encoding

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Memory Research

Background:

• Attention is crucial for episodic memory encoding, but the distinct roles of top-down (TDA) and bottom-up attention (BUA) remain unclear.
• Understanding these attentional mechanisms is key to deciphering memory formation processes.

Purpose of the Study:

• To investigate how top-down attention (TDA) and bottom-up attention (BUA) differentially influence episodic memory encoding.
• To explore the neural correlates of attention-modulated memory encoding using functional magnetic resonance imaging (fMRI).

Main Methods:

• Implemented a novel fMRI task distinguishing TDA (visual search) from BUA (stimulus-driven capture) during incidental encoding.
• Subjects performed semantic categorization, followed by a surprise recognition test.
• Analyzed univariate and psychophysiological interaction (PPI) effects to assess brain activity and functional connectivity.

Main Results:

• Ventral visual regions and the right hippocampus correlated with successful encoding.
• During TDA, increased parietal-fusiform coupling was linked to encoding failure, while occipital-fusiform coupling predicted success.
• No significant connectivity changes were observed during BUA.

Conclusions:

• Top-down attention, mediated by parietal cortex, may hinder memory encoding by prioritizing task execution over stimulus processing.
• Enhanced connectivity within the ventral visual cortex supports feature integration and promotes memory encoding.
• The impact of attention on memory encoding is task-dependent, with higher cognitive control potentially impairing memory performance.