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Spike Rate (spike + rate)

Distribution by Scientific Domains
Life Sciences100%

Selected Abstracts

Developmental experience alters information coding in auditory midbrain and forebrain neurons

DEVELOPMENTAL NEUROBIOLOGY, Issue 4 2010
Sarah M.N. Woolley
Abstract In songbirds, species identity and developmental experience shape vocal behavior and behavioral responses to vocalizations. The interaction of species identity and developmental experience may also shape the coding properties of sensory neurons. We tested whether responses of auditory midbrain and forebrain neurons to songs differed between species and between groups of conspecific birds with different developmental exposure to song. We also compared responses of individual neurons to conspecific and heterospecific songs. Zebra and Bengalese finches that were raised and tutored by conspecific birds, and zebra finches that were cross-tutored by Bengalese finches were studied. Single-unit responses to zebra and Bengalese finch songs were recorded and analyzed by calculating mutual information (MI), response reliability, mean spike rate, fluctuations in time-varying spike rate, distributions of time-varying spike rates, and neural discrimination of individual songs. MI quantifies a response's capacity to encode information about a stimulus. In midbrain and forebrain neurons, MI was significantly higher in normal zebra finch neurons than in Bengalese finch and cross-tutored zebra finch neurons, but not between Bengalese finch and cross-tutored zebra finch neurons. Information rate differences were largely due to spike rate differences. MI did not differ between responses to conspecific and heterospecific songs. Therefore, neurons from normal zebra finches encoded more information about songs than did neurons from other birds, but conspecific and heterospecific songs were encoded equally. Neural discrimination of songs and MI were highly correlated. Results demonstrate that developmental exposure to vocalizations shapes the information coding properties of songbird auditory neurons. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 70: 235,252, 2010. [source]

Lateralized functional components of spatial cognition in the avian hippocampal formation: Evidence from single-unit recordings in freely moving homing pigeons

HIPPOCAMPUS, Issue 2 2006
Jennifer J. Siegel
Abstract Previous research has revealed that the functional components of spatial cognition are lateralized in the forebrain of birds, including the hippocampal formation (HF). To investigate how HF cells in the left and right avian brain may differentially participate in representations of space, we recorded single-units from the HF of homing pigeons as they ran a plus maze for food. The rate maps of left HF cells often displayed elongated regions of increased activity in the center of the maze and along the maze corridors, whereas right HF cells tended to display patches at the ends of maze arms at/near goal locations. Left HF cells displayed a higher degree of spatial-specificity compared with right HF cells, including higher patch-specificity, higher reliability, and a higher incidence of location-correlated activity. Analysis of speed-correlated and trajectory-dependent activity also revealed significant HF-lateralized differences. Right HF cells tended to display significant negative correlations between spike rate and speed, although speed-dependent rate maps indicate that this relationship did not explain their space-specific activity. Left HF cells displayed a significantly higher incidence of trajectory-dependent space-specific activity than was observed in the right HF, suggesting that left HF cells may participate in navigating among goal locations. Differences in the correlates of left and right pigeon HF cells are consistent with unilateral HF-lesion data suggesting that the functional components of spatial cognition are lateralized in the avian brain, and furthermore, provide a basis for hypotheses regarding how the left and right HF support different aspects of spatial cognition. © 2005 Wiley-Liss, Inc. [source]

Developmental experience alters information coding in auditory midbrain and forebrain neurons

DEVELOPMENTAL NEUROBIOLOGY, Issue 4 2010
Sarah M.N. Woolley
Abstract In songbirds, species identity and developmental experience shape vocal behavior and behavioral responses to vocalizations. The interaction of species identity and developmental experience may also shape the coding properties of sensory neurons. We tested whether responses of auditory midbrain and forebrain neurons to songs differed between species and between groups of conspecific birds with different developmental exposure to song. We also compared responses of individual neurons to conspecific and heterospecific songs. Zebra and Bengalese finches that were raised and tutored by conspecific birds, and zebra finches that were cross-tutored by Bengalese finches were studied. Single-unit responses to zebra and Bengalese finch songs were recorded and analyzed by calculating mutual information (MI), response reliability, mean spike rate, fluctuations in time-varying spike rate, distributions of time-varying spike rates, and neural discrimination of individual songs. MI quantifies a response's capacity to encode information about a stimulus. In midbrain and forebrain neurons, MI was significantly higher in normal zebra finch neurons than in Bengalese finch and cross-tutored zebra finch neurons, but not between Bengalese finch and cross-tutored zebra finch neurons. Information rate differences were largely due to spike rate differences. MI did not differ between responses to conspecific and heterospecific songs. Therefore, neurons from normal zebra finches encoded more information about songs than did neurons from other birds, but conspecific and heterospecific songs were encoded equally. Neural discrimination of songs and MI were highly correlated. Results demonstrate that developmental exposure to vocalizations shapes the information coding properties of songbird auditory neurons. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 70: 235,252, 2010. [source]