Seasonal plasticity in the song nuclei of wild rufous-sided towhees

  title={Seasonal plasticity in the song nuclei of wild rufous-sided towhees},
  author={G T Smith},
  journal={Brain Research},
  • G. T. Smith
  • Published 23 September 1996
  • Biology, Environmental Science
  • Brain Research

Failure to detect seasonal changes in the song system nuclei of the black-capped chickadee (Poecile atricapillus).

It is suggested that the song system of males is larger than that of females, as is typical in songbirds, but the ratio between the sexes is small compared to other species.

Seasonal plasticity of the song control system in wild Nuttall's white-crowned sparrows.

There is seasonal plasticity of the song system in wild Nuttall's white-crowned sparrows, which can be regarded as a common feature of the seasonally breeding songbirds studied thus far.

Seasonal changes in intrinsic electrophysiological activity of song control neurons in wild song sparrows

It is concluded that environmental cues are sufficient to induce seasonal changes in electrophysiological properties of song control neurons, and that changes in these properties may underlie seasonally changes in song behavior.

Estrogen contributes to seasonal plasticity of the adult avian song control system.

It is demonstrated that estrogen can affect adult neural plasticity on a gross anatomical scale and that estradiol has neurotrophic effects in adult male songbirds, the first examination of estrogen effects on the brain of a wild animal.

Seasonal rewiring of the songbird brain: an in vivo MRI study

An unexpectedly broad plasticity in the connectivity of the avian brain that might be involved in preparing subjects for the competitive and demanding behavioral tasks that are associated with successful reproduction is demonstrated.

Neuroendocrinology of Song Behavior and Avian Brain Plasticity: Multiple Sites of Action of Sex Steroid Hormones

Testosterone effects on neuroplasticity in the song system may be indirect in that behavioral activity stimulated by testosterone acting in sites that promote male sexual behavior could in turn promote morphological changes in thesong system.

Androgen control of vocal control region volumes in a wild migratory songbird (Junco hyemalis) is region and possibly age dependent.

Investigation of naturally occurring seasonal changes in the sizes of vocal control regions in a wild migratory species with samples from adolescence to post-breeding fall migration finds that area X size in adolescent male juncos may be testosterone independent.

Neuroendocrine control of song in the dark-eyed junco (Junco hyemalis)

It is found that, in males, photoperiodic condition and testosterone interact to regulate seasonal VCR volume plasticity, whereas testosterone alone controls song production.

Roles of photoperiod and testosterone in seasonal plasticity of the avian song control system.

Although testosterone is the primary factor mediating seasonal changes in neural attributes of the song nuclei, photoperiod may act via mechanisms that are independent of steroid levels to supplement or modulate the actions of testosterone.



Seasonal changes in song nuclei and song behavior in Gambel's white-crowned sparrows.

Seasonal changes in the song control nuclei may correlate with seasonal changes in song stereotypy in male white-crowned sparrows of the migratory Gambel's subspecies are hypothesized.

Seasonal changes in avian song nuclei without seasonal changes in song repertoire

Seasonal variation in the size of song nuclei in the brains of male songbirds may be related to the ability to learn to sing new songs as adults, and synaptic plasticity provided by such seasonal variation may enable song learning by adult birds.

Song-related brain regions in the red-winged blackbird are affected by sex and season but not repertoire size.

Seasonal change in song system structures in male redwings is consistent with there being a relation between adult plasticity in anatomy and in behavior; the large seasonal change in these structures in females suggests large seasonal changes in the function of these nuclei.

A brain for all seasons: cyclical anatomical changes in song control nuclei of the canary brain.

Male canaries that have reached sexual maturity can, in subsequent years, learn new song repertoires and two telencephalic song control nuclei are hypothesized to reflect an increase and then reduction in numbers of synapses and are related to the yearly ability to acquire new motor coordinations.

Matters of life and death in the songbird forebrain.

The relationships between cellular and behavioral aspects of song learning in both zebra finches and canaries are reviewed, as well as the role of gonadal hormones in regulating diverse aspects of the song-control system.

Sexual dimorphism in vocal control areas of the songbird brain.

In canaries and zebra finches, three vocal control areas in the brain are strikingly larger in males than in females, believed to be the first report of such gross sexual dimorphism in a vertebrate brain.

Hormone-induced changes in identified cell populations of the higher vocal center in male canaries.

The results of this study show that steroid hormones exert potent effects on HVC morphology in male canaries, but differences between the results and studies of seasonal males suggest there may be additional factors that can regulate HVC Morphology.