Functional role and plasticity of brain areas in spiders

• Applicant: Professorin Dr. Gabriele Beate Uhl
• Subject Area: Systematics and Morphology (Zoology)
• Term: from 2018 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 419146971

The central nervous system (CNS) of animals integrates and coordinates information in specific processing areas and is responsible for behavioural decisions. On the one hand, behavioural responses can be plastic depending on the amount and type of information received, and on the other hand, the anatomy of the CNS areas themselves is subject to plasticity depending on the stimuli provided by the environment during development or adulthood. In this project, we investigate the anatomy of brains and the functional role and plasticity of their processing areas. We use spiders as target group since knowledge on spider brains is scarce compared to other arthropods. First, we compare brain anatomy in spiders with different modes of life - two cursorial hunters and two web-building stationary hunters. Thereby we assess differences in the structure, number and arrangement of neuropils - the processing areas of their CNS. This comparative approach allows predictions on the functional roles of specific neuropils. Secondly, using one species from each group, we investigate neuroplastic responses of the supposed major processing neuropils to a vibratory and/or visually stimulating environment. We will quantify the volume of neuropils and the number and density of synaptic complexes. In a third, more explorative approach, the hypotheses on neuropil functions are tested by means of electrophysiological recordings of the responses of neuropils to vibratory and visual stimuli in the living spider. We use a combination of methods for these complementary approaches: histology, microCT, immunohistology, differentially stimulating environments and electrophysiology.The project will have implications on different levels. It will provide information on anatomy and function of specific brain areas that may lead to a reassessment of hypotheses on the evolution of the arthropod brain. Likewise, the study contributes to the growing field of cognition research by providing information on the degree of neuroplasticity in response to different environmental conditions.

• DFG Programme: Research Grants