Locomotion in the decerebrate stingray

Area of Science:

• Neuroscience
• Marine Biology
• Animal Locomotion

Background:

• Stingrays exhibit a unique pectoral fin movement for swimming, involving active elevation-depression.
• Previous research suggests a central pattern generator (CPG) may underlie rhythmic movements in aquatic animals.

Purpose of the Study:

• To investigate the neural control of locomotion in stingrays.
• To determine the role of the brain and spinal cord in coordinating pectoral fin movements during swimming.

Main Methods:

• High decerebration was performed on stingrays to isolate brainstem and spinal cord functions.
• Electromyographic recordings were used to analyze muscle activity patterns during locomotion.
• Spinal cord transections were performed to assess the necessity of spinal circuits for movement.

Main Results:

• Decerebrated stingrays maintained locomotion with muscle activity patterns similar to intact animals.
• Spontaneous and midbrain-evoked rhythmic motoneuron activity was observed in paralyzed, decerebrated stingrays.
• Stingrays with high spinal transections were unable to locomote, unlike dogfish sharks.

Conclusions:

• The midbrain plays a crucial role in initiating and coordinating stingray locomotion.
• Spinal cord circuits are essential for the execution of forward locomotion in stingrays.
• Stingray locomotion control differs significantly from that of sharks, highlighting diverse neural strategies in aquatic locomotion.