Specific wiring of distinct amacrine cells in the directionally selective retinal circuit permits independent coding of direction and size.
Neuron
; 86(1): 276-91, 2015 Apr 08.
Article
em En
| MEDLINE
| ID: mdl-25801705
ABSTRACT
Local and global forms of inhibition controlling directionally selective ganglion cells (DSGCs) in the mammalian retina are well documented. It is established that local inhibition arising from GABAergic starburst amacrine cells (SACs) strongly contributes to direction selectivity. Here, we demonstrate that increasing ambient illumination leads to the recruitment of GABAergic wide-field amacrine cells (WACs) endowing the DS circuit with an additional feature size selectivity. Using a combination of electrophysiology, pharmacology, and light/electron microscopy, we show that WACs predominantly contact presynaptic bipolar cells, which drive direct excitation and feedforward inhibition (through SACs) to DSGCs, thus maintaining the appropriate balance of inhibition/excitation required for generating DS. This circuit arrangement permits high-fidelity direction coding over a range of ambient light levels, over which size selectivity is adjusted. Together, these results provide novel insights into the anatomical and functional arrangement of multiple inhibitory interneurons within a single computational module in the retina.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Retina
/
Percepção Espacial
/
Percepção de Tamanho
/
Células Amácrinas
/
Rede Nervosa
Limite:
Animals
Idioma:
En
Revista:
Neuron
Assunto da revista:
NEUROLOGIA
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Canadá