Date of Award


Document Type

Union College Only

Degree Name

Bachelor of Science



First Advisor

Robert Olberg




dragonfly, spatial, prey, object, movement, visual information


A group of 16 large visual neurons in the dragonfly brain is known to send visual information to the thorax to control flight. Specifically these neurons convey information about the location and direction of object movement. Past findings have indicated that increased temperature leads to a greater responsiveness of these neurons. Although the visual responses of these “target-selective” neurons have been studied at length, detailed knowledge about the limits of their spatial and temporal resolution is lacking. In our experiment we took extracellular recordings of TSDN activity from the ventral nerve cord. We presented the animal with visual stimuli of different sizes and speeds at two different head temperatures (22° Celsius and 30°). Our results indicate that raising the dragonfly’s temperature increases the responsiveness of the target selective descending neurons, resulting in increased spike activity in response to faster and smaller targets. In addition raising the temperature resulted in decreased spike widths. Determining the limits of target selective neurons is essential for understanding the restrictions of the compound eye, and specifically for understanding the remarkable ability of the dragonfly to intercept small, fast moving, flying prey.