Neural Substrates of Attentional Control During Emotional Processing: Evidence From rTMS-fMRI Targeting the Frontal...

Area of Science:

• Neuroscience
• Cognitive Psychology
• Neuroimaging

Background:

• Conflicting evidence exists on whether amygdala emotional processing is independent of or dependent on selective attention.
• Understanding the interplay between attention and emotion processing is crucial for explaining neural responses to various stimuli.

Purpose of the Study:

• To investigate how perturbing top-down attentional control affects neural responses to emotional and neutral stimuli.
• To examine the role of the right frontal eye field (FEF) in modulating visual cortex and amygdala activity during emotional perception.

Main Methods:

• Combined repetitive transcranial magnetic stimulation (rTMS) targeting the right frontal eye field (FEF) with functional magnetic resonance imaging (fMRI).
• Participants performed a visual matching task involving houses and neutral or fearful faces while ignoring irrelevant stimuli.
• Two experimental sessions were conducted: one with rTMS and one without (control), in a counterbalanced order.

Main Results:

• Right FEF rTMS selectively slowed behavioral responses to neutral faces but not fearful faces.
• Functional magnetic resonance imaging (fMRI) revealed reduced fusiform face area (FFA) responses to neutral faces post-rTMS, while responses to fearful faces remained intact.
• Amygdala responses to fearful faces were preserved or even increased after FEF rTMS, unlike responses to neutral stimuli.

Conclusions:

• Neural responses to emotionally salient (fearful) stimuli appear less dependent on top-down attentional modulation compared to neutral stimuli.
• Findings support models suggesting distinct attentional and emotional processing networks.
• The right FEF plays a role in attentional control over neutral visual stimuli processing but not emotional ones.