Night-time neuronal activation of Cluster N in a day- and night-migrating songbird

Eur J Neurosci. 2010 Aug;32(4):619-24. doi: 10.1111/j.1460-9568.2010.07311.x. Epub 2010 Jul 6.

Abstract

Magnetic compass orientation in a night-migratory songbird requires that Cluster N, a cluster of forebrain regions, is functional. Cluster N, which receives input from the eyes via the thalamofugal pathway, shows high neuronal activity in night-migrants performing magnetic compass-guided behaviour at night, whereas no activation is observed during the day, and covering up the birds' eyes strongly reduces neuronal activation. These findings suggest that Cluster N processes light-dependent magnetic compass information in night-migrating songbirds. The aim of this study was to test if Cluster N is active during daytime migration. We used behavioural molecular mapping based on ZENK activation to investigate if Cluster N is active in the meadow pipit (Anthus pratensis), a day- and night-migratory species. We found that Cluster N of meadow pipits shows high neuronal activity under dim-light at night, but not under full room-light conditions during the day. These data suggest that, in day- and night-migratory meadow pipits, the light-dependent magnetic compass, which requires an active Cluster N, may only be used during night-time, whereas another magnetosensory mechanism and/or other reference system(s), like the sun or polarized light, may be used as primary orientation cues during the day.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animal Migration / physiology*
  • Animals
  • Behavior, Animal / physiology
  • Cues
  • Darkness*
  • Early Growth Response Protein 1 / genetics
  • Early Growth Response Protein 1 / metabolism
  • Gene Expression Regulation
  • Light*
  • Magnetics
  • Neurons / cytology
  • Neurons / physiology*
  • Orientation / physiology
  • Photic Stimulation
  • Songbirds* / anatomy & histology
  • Songbirds* / physiology

Substances

  • Early Growth Response Protein 1