Current Research Interests/Projects:
For the past 34 years, our laboratory has been dedicated to the analysis of the neural mechanisms underlying aggression and rage behavior in the cat. These studies have enabled us to identify: (1) the neural structures that mediate feline defensive rage and predatory attack behavior; (2) the neural structures that modulate and control these forms of aggression; (3) the neural circuitry by which aggression and rage are expressed and modulated; and (4) the neurotransmitter receptor mechanisms associated with these circuits. Recent neurotransmitter receptor systems examined in our laboratory include: enkephalinergic mechanisms associated with the central nucleus of amygdala and midbrain periaqueductal gray (PAG), substance P mechanisms linked to the medical amygdala, septal area and medial hypothalamus, NMDA receptors associated with the PAG with respect to the expression of defensive rage behavior, CCK receptors within the PAG, and GABA mechanisms within the hypothalamus and PAG. Ongoing studies in our laboratory utilize brain stimulation, behavioral pharmacological, immuncytochemical and anatomical methods to develop a better understanding of the neural mechanisms that control aggression and rage behavior. Other recent studies have begun to identify how stimulation and seizures of the amygdala and related structures associated with aggression and rage affect immunological responses.

Representative Publications:

Siegel, A., Schubert, K. And Shaikh, M.B. Neurotransmitters regulating defensive rage behavior in the cat. Neurosciences and Biobehavioral Reviews, 21: 733-742 (1997).

Han, Y., Shaikh, M.B. and Siegel, A. Ethanol enhances medial amygdaloid induced inhibition predatory attack behavior in the cat: role of GABAAreceptors in the lateral hypothalamus. Alcohol and Alcoholism, 32:657-670 (1997).

Shaikh, M.B., De Lanerolle, N., and Siegel, A. Serotonin 5-HT1A and 5-HT2/1C receptors in the midbrain periaqueductal gray differentially modulate defensive rage behavior elicited from the medial hypothalamus of the cat. Brain Research, 765: 198-207 (1997).

Cheu, J.W. and Siegel, A. GABA receptor mediated suppression of defensive rage behavior elicited from the medial hypothalamus of the cat: role of the lateral hypothalamus. Brain Research, 783:293-304 (1998).

Luo, B., J. Cheu, and A. Siegel. Cholecystokinin B receptors in the periaqueductal gray potentiate defensive rage behavior elicited from the medial hypothalamus of the cat. Brain Research, 796: 27-37 (1998).

Siegel, A. and Siegel, H. Neuroscience, Self Assessment and Review. Third Edition. McGraw Hill. New York , 1998.

Siegel, A., T.A.P. Roeling, T.R. Gregg and Kruk, M.R. The neuropharmacology of brain stimulation evoked aggression. Neuroscience & Biobehavioral Reviews, 23: 359-389 (1999).

Yao , R., P. Rameshwar, R.J. Donnelly and A. Siegel. Neurokinin-1 expression and co-localization with glutamate and GABA. Molecular Brain Research, 71: 149-158 (1999).

Gregg, T. and A. Siegel. Brain structures and neurotransmitters regulating aggression in cats: implications for human aggression. Neuro-psychopharmacology & Biological Psychiatry, (2001) 25: 91-140.