BOLD repetition decreases in object-responsive ventral visual areas depend on spatial attention

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neuroimaging

Background:

• Functional imaging studies extensively use repetition suppression to investigate neural object representation.
• The role of spatial attention in blood oxygenation level-dependent (BOLD) repetition effects remains largely unexplored, despite BOLD decreases sometimes occurring without awareness of repetition.

Purpose of the Study:

• To investigate whether BOLD repetition decreases in ventral visual cortices are contingent upon the allocation of spatial attention to the prime object.
• To determine the influence of attention on neural and behavioral priming effects.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was employed in 13 healthy participants.
• Participants performed a size-judgment task on probe objects following attended or ignored lateralized prime displays.
• Behavioral reaction times and BOLD signal changes were analyzed.

Main Results:

• Faster reaction times were observed for probes matching attended primes, irrespective of view (identical or mirror image).
• No behavioral effects were found for unattended primes.
• BOLD repetition decreases were detected in bilateral lateral occipital and fusiform regions for attended primes, generalizing across identical and mirror-image repeats.
• No repetition decreases were observed for ignored primes.

Conclusions:

• Attention plays a crucial role in establishing visual object representations that elicit both BOLD signal decreases and behavioral priming.
• These findings highlight the interplay between attention, neural processing, and object recognition.