My research interests integrate neuroscience, endocrinology, and animal behavior. I focus on seasonal plasticity in the neuroendocrine mechanisms regulating complex social behavior, and seek to answer two fundamental questions:
- When similar behavior is observed in distinct contexts, are the neuroendocrine mechanisms underlying the expression of that behavior context-dependent?
- Are there context-dependent differences in how social experience influences the neuroendocrine regulation of social behavior?
I combine ethological, molecular, and biochemical techniques to address these questions in songbirds.
Songbirds in temperate latitudes experience profound seasonal changes in physiology and behavior. In the breeding season, circulating levels of gonadal hormones are elevated. This activates behaviors associated with reproduction including territory establishment/defense, courtship singing, and mating behavior. In the non-breeding season, circulating levels of gonadal hormones are undetectable. This inhibits reproduction in favor of behaviors associated overwinter survival.
Remarkably, in some species of songbird it is not uncommon for behaviors such as singing and territoriality to be observed in both the breeding and non-breeding seasons despite these marked differences in circulating hormone levels. However, the function of and underlying motivational state accompanying these behaviors differ context-dependently. My overarching hypothesis is that two interconnected circuits in the brain (the vertebrate “social behavior network” and avian “song control system”) regulate these behaviors context-dependently as well.
Papers & Presentations
- Prior NH, Heimovics SA, Soma KK (under review) “Effects of water restriction on reproductive physiology and affiliative behavior in an opportunistically-breeding and monogamous songbird, the zebra finch” Hormones and Behavior. Ms. No.: HB-12-207
- Heimovics SA, Fokodis HB, Soma KK (2012) “Brain Aromatase and Territorial Aggression Across the Seasons in Male Song Sparrow” in Brain aromatase, estrogens and behavior. Oxford University Press. Balthazart J and Ball GF eds.
- Heimovics SA, Prior NH, Maddison CJ, Soma KK (2012) “Rapid and widespread effects of 17?-estradiol on intracellular signaling in the male songbird brain: a seasonal comparison” Endocrinology. Mar; 153(3):1364-76
- Taves MD, Ma C, Heimovics SA, Saldanha CJ, Soma KK (2011) “Measurement of steroid concentrations in brain tissue: methodological considerations” Frontiers in Neuroendocrine Science. 2:39
- Heimovics SA, Salvante KG , Sockman KW, Riters LV (2011) “Context-dependent relationships between sexually and agonistically motivated song and indices of catecholamine neurotransmission in male European starlings (Sturnus vulgaris)” Hormones and Behavior. Nov;60(5):529-39
- Charlier TD, Newman AE, Heimovics SA, Po KL, Saldanha, CJ, Soma KK (2011) “Rapid effects of aggressive interactions on aromatase activity and oestradiol in discrete brain regions of wild male white-crowned sparrows” Journal of Neuroendocrinology. 23: 742-753
- Heimovics SA, Cornil CA, Ellis JF, Ball GF, Riters LV (2011) “Seasonal and individual variation in singing behavior relates to alpha 2-noradrenergic receptor density in brain regions implicated in song, social, and sexual behavior” Neuroscience. 182:133-43
- Heimovics SA, Cornil CA, Ball GF, Riters LV (2009). “D1-like dopamine receptor density in nuclei involved in social behavior correlates with song in a context-dependent fashion in male European starlings” Neuroscience. 159(3):962-73
- Heimovics SA, Riters LV (2008). “Evidence that dopamine within motivation and song control brain regions regulates birdsong context-dependently.” Physiology and Behavior. 95(1-2):258-66
- Heimovics SA, Riters LV (2007). “ZENK labeling within social behavior brain regions reveals breeding context-dependent patterns of neural activity associated with song in male European starlings (Sturnus vulgaris).” Behavioral Brain Research. 176(2):333-43
- Heimovics SA, Riters LV (2006). “Breeding context-dependent relationships between song and cFOS labeling within social behavior brain regions in male European starlings (Sturnus vulgaris).” Hormones and Behavior. 50(5):726-35
- Heimovics SA, Riters LV (2005). “Immediate early gene activity in song control nuclei and brain areas regulating motivation relates positively to singing behavior during, but not outside of, a breeding context.” Journal of Neurobiology. 65(3):207-24.
- Society for Behavioral Neuroendocrinology annual meeting (2011)
Abstract title: Noninvasive estradiol treatment rapidly increases aggression in male song sparrows
- Society for Neuroscience annual meeting (2010)
Abstract title: Rapid effects of estradiol on signaling cascades in male song sparrow brain: is there a seasonal difference?
- Society for Neuroscience annual meeting (2008)
Abstract title: “Context-dependent relationships between sexually and agonistically motivated song and indices of catecholamine neurotransmission in male European starlings (Sturnus vulgaris)”
- Society for Neuroscience annual meeting (2007)
Abstract title: “D1 and D2 dopamine receptor densities in male European starlings (Sturnus vulgaris) in different reproductive states”
- Society for Behavioral Neuroendocrinology annual meeting (2007)
Abstract title: “Breeding context-dependent relationships between song and dopaminergic markers in song control and social behavior nuclei in male European starlings (Sturnus vulgaris)”
- Society for Neuroscience annual meeting (2005)
Abstract title: “The effect of breeding condition on the relationships between song and the number of ZENK-labeled cells in regions within and outside of the song control system in male European starling”
- Society for Neuroscience annual meeting (2004)
Abstract title: "Song relates positively to immediate early gene activity within the POM and VTA in spring, but not fall, in male European starlings”
- Canadian Institute of Health Research (CIHR) Postdoctoral Fellowship (2010-2013)
- Michael Smith Foundation for Health Research (MSFHR) Postdoctoral Fellowship (2009-2012)
- National Science Foundation (NSF) Graduate Research Fellowship (2003-2006)