Object discrimination through active electrolocation: Shape recognition and the influence of electrical noise
Sarah Schumacher1, Theresa Burt de Perera2, Gerhard von der Emde1
1Institut für Zoologie, Universität Bonn, Endenicher Allee 11-13, 53115 Bonn, Germany.
Journal of Physiology, Paris
|December 17, 2016
Summary
Weakly electric fish use movement-induced modulations for shape recognition. They also show remarkable immunity to jamming from conspecifics
Area of Science:
- Neuroethology
- Sensory Biology
- Animal Behavior
Background:
- Weakly electric fish (Gnathonemus petersii) utilize active electrolocation for object recognition.
- Object shape recognition remains poorly understood, with no single electrical image parameter encoding shape.
- Electrical noise from conspecifics poses a potential challenge to electrolocation.
Purpose of the Study:
- To investigate if movement-induced modulations (MIM) influence shape recognition in electric fish.
- To determine the effect of electrical noise from conspecifics on object discrimination performance.
Main Methods:
- Fish were trained to discriminate objects based on varying levels of MIM.
- Object discrimination was tested in the presence of conspecifics or playback electrical noise.
- Electric signals and discrimination performance were recorded.
Main Results:
- Fish could discriminate objects at greater distances when MIM differences were larger, suggesting MIM involvement in shape recognition.
- One fish's discrimination performance dropped significantly with high noise overlap, while the other remained unaffected.
- Neither fish altered their electric organ discharge (EOD) pulsing behavior to avoid jamming.
Conclusions:
- Movement-induced modulations likely contribute to shape recognition in weakly electric fish.
- Electric fish exhibit surprising resilience to jamming by conspecific electrical noise.
- Jamming avoidance strategies were not evident in the tested fish's pulsing behavior.
