Donna Jean Cross PhD, Presenter: Nothing to Disclose

Robert Miyaoka PhD, Abstract Co-Author: Research Grant, Koninklijke Philips Electronics NV Research Grant, Zecotek Photonics Inc

Satoshi Minoshima MD, PhD, Abstract Co-Author: License agreement, General Electric Company Research Grant, Koninklijke Philips Electronics NV Research Grant, Nihon Medi-Physics Co, Ltd Research Grant, Hitachi, Ltd Consultant, Hamamatsu Photonics KK

John Marzluff, Abstract Co-Author: Nothing to Disclose

Neuronal mechanisms of fear underlie psychiatric disorders such as post-traumatic stress. Crows remember brief encounters with specific humans associated with threat or harm. We used molecular imaging, microPET and [F-18]FDG, to investigate neural correlates underlying a crow’s response to danger including threatening humans and predators (hawk).

Crows (Corvus brachyrhynchos n=19) were caught by researchers wearing masks. For stimulus condition, eyes-covered crows received 1mCi FDG ip. During uptake, awake crows were shown; 1) face that captured it (THREAT), 2) new face holding a dead crow (DEAD), 3) robotic-operated hawk (HAWK), or 4) empty room, in 1m on / 30s off blocks for 11m. After stimulation crows were anesthetized and imaged in microPET. Image timing for fast bird metabolism determined by pilot scan. Reconstructed images were aligned to crow atlas stereotactically and global normalized. Voxelwise Z-maps evaluated group changes of different stimulations versus empty room.

THREAT group activated arcopallium (A) (11% Z=4.4), brainstem (5.9% Z=4.2) and nido/mesopallium (N/M) (12.9% Z=4.1) where descending tracts from A (amygdala analog) are involved in conditioned fear responses. DEAD group activated optic tectum (5% Z=4.4), mesopallium/hyperpallium apicale (M/HA) (12% Z=4.2), cerebellum (16% Z=3.8) and hippocampus (10% Z=3.5) indicating activation of tectofugal visual pathway and networks involved in spatial learning of new dangerous face with dead crow. This contrasted to regions activated by natural danger (HAWK) which showed little forebrain processing but use of the thalamofugal visual pathway; nidopallium caudale (17% Z=4.2), nidopallium caudolaterale (7% Z=4.1) N/M (7% Z=4.1) and HA (9% Z=4.0).

This novel application of microPET to crows perceiving a threat found activation patterns analogous to human emotion/fear processing. Results suggest that crows recognize faces by evaluating visual information in the context of learned associations. Although some gross structural overlap was seen, FDG microPET revealed subregional spatial differences in processing of different fear/threat paradigms, which have not been seen previously using post-mortem anatomical methods.

This study provides new knowledge of differential fear processing, which may have implications for disorders such as PTSD as well as diseases with deficits in face recognition such as autism.

Cross, D, Miyaoka, R, Minoshima, S, Marzluff, J, Metabolic Brain Mapping Analysis of the Neural Response to Threatening Human Faces vs Predators in the Wild American Crow by microPET.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12030847.html