An Experimental Approach to Investigating Effects of Artificial Light at Night on Free-Ranging Animals: Implementation, Results, and Directions for Future Research

Animals have evolved with natural patterns of light and darkness. However, artificial light is being increasingly introduced into the environment from ...

University of Antwerp

The song control system (SCS) of seasonal songbirds shows remarkable seasonal plasticity. Male starlings (Sturnus vulgaris) sing throughout the year, but in the breeding season, when concentrations of testosterone are elevated, the song is highly sexually motivated. The main goal of this study was to investigate structural seasonal changes in regions involved in auditory processing and in socio-sexual behavior. Using in vivo Diffusion Tensor Imaging (DTI), we measured in breeding and nonbreeding seasons volume and tissue characteristics of several brain regions of nine adult male starlings. We demonstrate that the songbird brain exhibits an extreme seasonal plasticity not merely limited to the SCS. Volumetric analysis showed seasonal telencephalon volume changes and more importantly also a volumetric change in the caudal region of the nidopallium (NCM), a region analogous to the mammalian secondary auditory cortex. Analysis of the DTI data allowed detection of seasonal changes in cellular attributes in NCM and regions involved in social behavior. This study extends our view on a seasonally dynamic avian brain which not only hones its song control system but also auditory and social systems to be prepared for the breeding season.

Structural changes between seasons in the songbird auditory forebrain.

Le syst&egrave;me de contr&ocirc;le de la chanson (SCS) des oiseaux chanteurs saisonni&egrave;res montre remarquable plasticit&eacute; saisonnier. M&acirc;le sansonnet (Sturnus vulgaris) chante tout au long de l&#39;ann&eacute;e, mais dans la saison de reproduction, lorsque les concentrations de testost&eacute;rone sont &eacute;lev&eacute;es, la chanson est sexuellement tr&egrave;s motiv&eacute;e. L&#39;objectif principal de cette &eacute;tude &eacute;tait d&#39;&eacute;tudier les changements saisonniers structurels r&eacute;gions impliqu&eacute;es dans le traitement auditif et de comportement socio-sexuelle. L&#39;utilisation in vivo Diffusion Tensor Imaging (DTI), nous avons mesur&eacute; en &eacute;levage et reproductrices saisons caract&eacute;ristiques de volume et de tissus de plusieurs r&eacute;gions du cerveau de neuf &eacute;tourneaux m&acirc;les adultes. Nous d&eacute;montrons que le cerveau d&#39;oiseau chanteur montre une extr&ecirc;me plasticit&eacute; saisonnier ne consiste pas seulement limit&eacute;e &agrave; la SCS. Analyse volum&eacute;trique a montr&eacute; des variations de volume saisonnier t&eacute;lenc&eacute;phale et, plus important encore, un changement volum&eacute;trique dans la r&eacute;gion caudale de la nidopallium (SUP), une r&eacute;gion analogue au cortex auditif secondaire chez les mammif&egrave;res. Analyse des donn&eacute;es DTI a permis la d&eacute;tection des changements saisonniers dans attributs cellulaires dans les r&eacute;gions et Mr impliqu&eacute;s dans le comportement social. Cette &eacute;tude s&#39;&eacute;tend notre point de vue sur un dynamique saisonni&egrave;re cerveau aviaire qui aiguise non seulement son syst&egrave;me de contr&ocirc;le de la chanson, mais aussi les syst&egrave;mes auditif et sociales &agrave; se pr&eacute;parer &agrave; la saison de reproduction.

Changements structurels entre les saisons dans le prosenc&eacute;phale auditif songbird.

Il sistema di controllo della canzone (SCS) di uccelli canori stagionale dimostra notevole plasticit&agrave; stagionale. Maschi storni (Sturnus vulgaris) cantano durante tutto l&#39;anno, ma durante la stagione riproduttiva, quando le concentrazioni di testosterone sono elevati, la canzone &egrave; altamente sessualmente motivata. L&#39;obiettivo principale di questo studio era di indagare i cambiamenti stagionali strutturali nelle regioni coinvolte nell&#39;elaborazione uditiva e nel comportamento socio-sessuale. Usando in vivo Diffusion Tensor Imaging (DTI), abbiamo misurato in allevamento e animaliste stagioni caratteristiche volume e tessuti di diverse regioni del cervello di nove adulti maschi storni. Dimostriamo che il cervello di songbird esibisce un&#39;estrema plasticit&agrave; stagionale non meramente limitato per la SCS. Analisi volumetrica hanno mostrato variazioni di volume del telencefalo stagionale e soprattutto anche un cambiamento volumetrico della regione caudale della nidopallium (NCM), una regione analoga alla corteccia uditiva secondaria dei mammiferi. Analisi dei dati DTI consentito rilevazione dei cambiamenti stagionali in attributi cellulari NCM e nelle regioni coinvolte nel comportamento sociale. Questo studio si estende la nostra vista su un cervello aviario stagionalmente dinamico che non solo affina il suo sistema di controllo della canzone ma anche sistemi uditivi e sociali per essere pronti per la stagione degli amori.

Geert Eens

Department of Biology,
Behavioural Ecology and Ecophysiology Group,
Department of Biology, Behavioural Ecology and Ecophysiology Group

University of Antwerp

An Experimental Approach to Investigating Effects of Artificial Light at Night on Free-Ranging Animals: Implementation, Results, and Directions for Future Research

Geert Eens

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Department of Biology,Behavioural Ecology and Ecophysiology Group,Department of Biology, Behavioural Ecology and Ecophysiology Group

University of Antwerp

An Experimental Approach to Investigating Effects of Artificial Light at Night on Free-Ranging Animals: Implementation, Results, and Directions for Future Research

Department of Biology,
Behavioural Ecology and Ecophysiology Group,
Department of Biology, Behavioural Ecology and Ecophysiology Group