The organization of receptive fields of an antero-medial group of spiking local interneurones in the locust with exteroceptive inputs from the legs

✍ Scribed by Toshiki Nagayama

• Book ID: 104657848
• Publisher: Springer
• Year: 1990
• Tongue: English
• Weight: 605 KB
• Volume: 166
• Category: Article
• ISSN: 0340-7594
• DOI: 10.1007/bf00192017

✦ Synopsis

1. The receptive fields of 18 spiking local interneurones with cell bodies in an antero-medial group and unilateral arborisations in the metathoracic ganglion of the locust Schistocerca gregaria were defined by intracellular recording while mechanically stimulating exteroceptors on the middle and hind legs.

2. The receptive fields on the hind leg ipsilateral to the arborizations are divisible into 3 general categories. First are fields that consist of distinct excitatory and inhibitory regions from receptors on different parts of the leg. The boundary between these regions is set by the dorso-ventral axis of the leg. Second are fields that are entirely excitatory and third are fields that are entirely inhibitory. These fields may cover the entire surface of the hind leg.

3. Sixteen of the interneurones also have receptive fields on the ipsilateral middle leg. These fields are either wholly excitatory or wholly inhibitory and may correspond in position to the field on the ipsilateral hind leg. Furthermore, many interneurones are also excited or inhibited by inputs from the contralateral middle or hind legs.

4. These interneurones integrate the mechanosensory signals from a hind leg in parallel with midline spiking local interneurones and should therefore play a role in the expression of local reflexes. Their wider receptive fields, however, suggests that they also influence the coordination between the legs in posture and locomotion.