title: Multimodal Imaging Evidence for a Frontoparietal Modulation of Visual Cortex during the Selective Processing of Conditioned Threat.
abstract: Emotionally salient cues are detected more readily, remembered better, and evoke greater visual cortical responses compared with neutral stimuli. The current study used concurrent EEG-fMRI recordings to identify large-scale network interactions involved in the amplification of visual cortical activity when viewing aversively conditioned cues. To generate a continuous neural signal from pericalcarine visual cortex, we presented rhythmic (10/sec) phase-reversing gratings, the orientation of which predicted the presence (CS+) or absence (CS-) of a cutaneous electric shock (i.e., the unconditioned stimulus). The resulting single trial steady-state visual evoked potential (ssVEP) amplitude was regressed against the whole-brain BOLD signal, resulting in a measure of ssVEP-BOLD coupling. Across all trial types, ssVEP-BOLD coupling was observed in both primary and extended visual cortical regions, the rolandic operculum, as well as the thalamus and bilateral hippocampus. For CS+ relative to CS- trials during the conditioning phase, BOLD-alone analyses showed CS+ enhancement at the occipital pole, superior temporal sulci, and the anterior insula bilaterally, whereas ssVEP-BOLD coupling was greater in the pericalcarine cortex, inferior parietal cortex, and middle frontal gyrus. Dynamic causal modeling analyses supported connectivity models in which heightened activity in pericalcarine cortex for threat (CS+) arises from cortico-cortical top-down modulation, specifically from the middle frontal gyrus. No evidence was observed for selective pericalcarine modulation by deep cortical structures such as the amygdala or anterior insula, suggesting that the heightened engagement of pericalcarine cortex for threat stimuli is mediated by cortical structures that constitute key nodes of canonical attention networks.
authors.affiliation: 1 University of Florida.
authors.forename: Nathan M
authors.initials: NM
authors.lastname: Petro
authors.affiliation: 1 University of Florida.
authors.forename: L Forest
authors.initials: LF
authors.lastname: Gruss
authors.affiliation: 1 University of Florida.
authors.forename: Siyang
authors.initials: S
authors.lastname: Yin
authors.affiliation: 1 University of Florida.
authors.forename: Haiqing
authors.initials: H
authors.lastname: Huang
authors.affiliation: 2 SUNY Binghamton.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Miskovic
authors.affiliation: 1 University of Florida.
authors.forename: Mingzhou
authors.initials: M
authors.lastname: Ding
authors.affiliation: 1 University of Florida.
authors.forename: Andreas
authors.initials: A
authors.lastname: Keil
mesh_terms: D000328:Adult; D003214:Conditioning, Classical / Q000502:physiology*; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005239:Fear / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000502:physiology*; D059907:Functional Neuroimaging / Q000379:methods*; D006624:Hippocampus / Q000000981:diagnostic imaging / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D064847:Multimodal Imaging; D010296:Parietal Lobe / Q000000981:diagnostic imaging / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D013788:Thalamus / Q000000981:diagnostic imaging / Q000502:physiology; D014793:Visual Cortex / Q000000981:diagnostic imaging / Q000502:physiology*; D055815:Young Adult