The specificity of central nervous projections of locust mechanoreceptors

Abstract

The central projections of hairplates and groups of campaniform sensilla of various parts of the locust head, neck, and thorax are compared. Receptors with approximately the same peripheral location (e.g., dorsal head, wing, or proximal leg) tend to exhibit similar central projection patterns. Specificity of the projections due to different morphological types of sensory neurones may influence shape and extent of segmental ramifications; this is observed with receptors of the proximal leg joints in particular.

Transplantation of neurons reveals processing areas and rules for synaptic connectivity in the cricket nervous system

“…For example, hair plate receptors, which provide information about leg position (Pearson, Wong, and Fourtner, 1976) project to intermediate neuropil (Braunig et al, 1983;Murphey et al, 1989;Pfluger et al, 198 1 ). Similarly, chordotonal organs, long known to function as proprioceptors (Field and Burrows, 1982;Zill, 1985), also project to this region (Braunig et al, 1981;Burrows, 1987;Laurent, 1987).…”

“…3 ) . This region of neuropil has been shown to be the termination site for a variety of sensory neurons that function as proprioceptors including CS located on the trochanter, femur, and tarsus of the leg (Hustert et al, 1981;Laurent and Hustert, 1988;Pfluger et al, 1988;Watson and England, 199 1 ), hair plate neurons (Braunig et al, 1983;Pfluger et al, 1981), and chordotonal organs (Braunig et al, 1981;Burrows, 1987;Laurent, 1987). Thus, group 6 CS afferents, which have been shown to function as proprioceptors (Zill and Moran,198 la,b) project to a region of neuropil in thoracic ganglia that processes proprioceptive information, and this layer will be called proprioceptive neuropil throughout this report.…”

“…The neurons of tactile hairs project into a ventral layer of neuropil in each segmental ganglion while the proprioceptive sense organs, such as hair plates and chordotonal organs, project into an intermediate layer. This principle of ganglionic organization has been demonstrated in a number of insects including the locust (Anderson, 1985;Braunig et al, 1981Braunig et al, , 1983Newland, 1991;Pfluger, Braunig, and Hustert, 1981), cricket (Hustert, 1978(Hustert, , 1985Johnson and Murphey, 1985;Murphey, Bacon, and Johnson, 1985), moth (Kent and Levine, 1988), and fly (Merritt and Murphey, 1992;Murphey et al, 1989). Furthermore, it has been demonstrated that interneurons receiving information of a particular modality have their dendrites restricted to the region of neuropil specific for that modality ( Burrows, 1992;Murphey, 1985;Siegler and Burrows, 1986).…”

Encoding of near-range spatial information by descending interneurons in the stick insect antennal mechanosensory pathway

“…In both cases, DINs may receive direct input from antennal mechanosensory afferents (e.g., Bräunig et al 1983). However, this work will provide the basis for a computational analysis of the population of antennal mechanosensory DINs in insects.…”

Sensory system in the wings red palm weevil Rhynchophorus ferrugineus

“…Most insects have IR receptors in wings. In locusts, sensory afferents originating from the wing tegula (Braunig et al 1983), from the wing-hinge stretch receptors (Altman and Tyrer, 1977), or from the wing itself (Braunig et al 1983) terminate plurisegmentally, as do wing afferents in the beetle Tenebrio (Breidbach, 1990) and in winged ants (Gronenberg and Peeters, 1993).…”