Harnessing Visual Unawareness in the Modulation of Fear

Poster Session B - Sunday, April 14, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Grace L.T. Lei^1,3, Tatia M.C. Lee^1,2,4, Charlene L.M. Lam^1,3; ¹The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China, ²Laboratory of Neuropsychology and Human Neuroscience, The University of Hong Kong, Hong Kong, China, ³Laboratory of Clinical Psychology and Affective Neuroscience, The University of Hong Kong, Hong Kong, China, ⁴Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangzhou, China

Anxiety and fear-related disorders are prevalent mental health problems. Exposure therapy is an evidence-based intervention for modulating fear and anxiety. However, negative emotional responses might be elicited during exposure and pre-mature dropouts are common. There is evidence suggesting that emotional processing and learning can take place without conscious awareness. Using a Pavlovian Conditioning model, the current study examined whether acquired threat could be modulated outside of visual awareness and the relevant neural mechanisms. In this 2-day fMRI study, participants learned to associate an aversive scream (unconditioned stimulus, US) to female faces (conditioned stimuli, CS) followed by extinction of the threat association on Day 1 and a test of return of fear on Day 2. Continuous flash suppression was employed to manipulate visual awareness during extinction, with moving circles presented to the dominant eye and the CS presented to the non-dominant eye in the unaware condition. Pupil dilation was recorded during the acquisition phase, whereas event-related bold signals were collected during the extinction and re-extinction phase. Results of the pupillary response indicated successful fear learning in the acquisition phase. In the extinction phase, enhanced activation in the dorsolateral prefrontal cortex (dlPFC) was observed during the presentation of CS+ compared to the trials of CS-, either within or outside of visual awareness. Our findings suggested that conditioned threat responses might be modulated outside of visual awareness, with the involvement of dlPFC.

Topic Area: EMOTION & SOCIAL: Other