Springer Online Journal Archives 1860-2000
Abstract Neurons in the brain of the spiny lobster that respond to chemical and mechanical stimulation of the antennule (antenna I) were recorded and stained intracellularly. Described here are neurons that do not arborize in the olfactory and accessory lobes of the deutocerebrum, but rather primarily target the lateral and/or the median antennular neuropils of the deutocerebrum. Some of the neurons also extend into the antennal and tegumentary neuropils of the tritocerebrum and the neuropils of the median protocerebrum. Included are antennular sensory afferents, antennular motoneurons, projection neurons descending from the central brain, projection neurons ascending from the central brain and projection neurons descending from the eyestalk ganglia. Collectively, these neurons consitutute a novel antennular sensory pathway that is parallel to and independent of the antennular olfactory pathway. The novel pathway integrates mechanosensory and non-olfactory chemosensory information in the lateral and/or the median antennular neuropils, which also serve as lower motor centers of the antennule. Division of the arthropod deutocerebrum into two, functionally distinct chemosensory pathways may reflect differences in how chemosensory information is processed that is fundamental to understanding the origin of the sense of smell.
Type of Medium: