GSTDTAP

浏览/检索结果: 共3条,第1-3条 帮助

已选(0)清除 条数/页:   排序方式:
Inversion of the Energetic Electron "Zebra Stripe" Pattern Present in the Earth's Inner Belt and Slot Region: First Observations and Interpretation 期刊论文
GEOPHYSICAL RESEARCH LETTERS, 2020, 47 (13)
作者:  Lejosne, Solene;  Mozer, F. S.
收藏  |  浏览/下载:22/0  |  提交时间:2020/06/16
zebra stripe inversion  energetic electrons  inner belt  slot region  electric fields  
Nearest neighbours reveal fast and slow components of motor learning 期刊论文
NATURE, 2020, 577 (7791) : 526-+
作者:  Kollmorgen, Sepp;  Hahnloser, Richard H. R.;  Mante, Valerio
收藏  |  浏览/下载:19/0  |  提交时间:2020/07/03

A new method for analysing change in high-dimensional data is based on nearest-neighbour statistics and is applied here to song dynamics during vocal learning in zebra finches, but could potentially be applied to other biological and artificial behaviours.


Changes in behaviour resulting from environmental influences, development and learning(1-5) are commonly quantified on the basis of a few hand-picked features(2-4,6,7) (for example, the average pitch of acoustic vocalizations(3)), assuming discrete classes of behaviours (such as distinct vocal syllables)(2,3,8-10). However, such methods generalize poorly across different behaviours and model systems and may miss important components of change. Here we present a more-general account of behavioural change that is based on nearest-neighbour statistics(11-13), and apply it to song development in a songbird, the zebra finch(3). First, we introduce the concept of '  repertoire dating'  , whereby each rendition of a behaviour (for example, each vocalization) is assigned a repertoire time, reflecting when similar renditions were typical in the behavioural repertoire. Repertoire time isolates the components of vocal variability that are congruent with long-term changes due to vocal learning and development, and stratifies the behavioural repertoire into '  regressions'  , '  anticipations'  and '  typical renditions'  . Second, we obtain a holistic, yet low-dimensional, description of vocal change in terms of a stratified '  behavioural trajectory'  , revealing numerous previously unrecognized components of behavioural change on fast and slow timescales, as well as distinct patterns of overnight consolidation(1,2,4,14,15) across the behavioral repertoire. We find that diurnal changes in regressions undergo only weak consolidation, whereas anticipations and typical renditions consolidate fully. Because of its generality, our nonparametric description of how behaviour evolves relative to itself-rather than to a potentially arbitrary, experimenter-defined goal(2,3,14,16)-appears well suited for comparing learning and change across behaviours and species(17,18), as well as biological and artificial systems(5).


  
A 'dynamic' landscape of fear: prey responses to spatiotemporal variations in predation risk across the lunar cycle 期刊论文
ECOLOGY LETTERS, 2017, 20 (11)
作者:  Palmer, M. S.;  Fieberg, J.;  Swanson, A.;  Kosmala, M.;  Packer, C.
收藏  |  浏览/下载:12/0  |  提交时间:2019/04/09
Anti-predator behaviour  buffalo  landscape of fear  lion  lunar cycle  predation risk  predator-prey interaction  Thomson'  s gazelle  wildebeest  zebra