University of Kentucky
Studies in Neurobiology: Study 2: Using Heart Rate as a Bioindex to Assess Various Sensory Perceptions in Sighted and Non-sighted Crayfish
Institution
University of Kentucky
Faculty Advisor/ Mentor
Robin Cooper; Sonya Bierbower
Abstract
Most organisms show diversity in the type and amount of peripheral sensors that enable detection of different sensory stimuli within and across multiple sensory modalities. Variation in sensory pathways allows organisms to monitor their environment, integrate sensory information from multiple sources, and respond accordingly, due to refined integration of information. Most invertebrates possess chemosensory neurons that permit identification of environmental chemicals and are able to behave differentially between chemical compounds based upon the sensory pathway stimulated (i.e., attractive and/or repellant). Current literature shows this is particularly true for decapod crustaceans in detecting chemical signals, especially in the cephalic and thoracic appendages. Crayfish are decapod crustaceans that rely on visual and chemical cues in the environment. Behavior studies alone often exclude “fight or flight” internal readiness changes and may conclude a lack of environmental awareness. Therefore, a “sympathetic-like” autonomic response (i.e., HR, heart rate and VR, ventilation rate) in crayfish, (surface) Procambarus clarkii and (cave) Orconectes australis packardi, during chemical introduction establishes chemical and/or modality sensitivities that may be species-specific. Preliminary findings suggest crayfish that show no behavioral response display an internal response through changes in HR/VR. Specifically, crayfish show an increase in HR with attractant chemical introductions (i.e., cysteine) suggesting a natural response to potential food sources, while showing more pronounced responses to toxic/warning compounds. Future research will include using chemical stimuli identified as significant to induce electrical impulses to be recorded within antennular olfaction neurons. Supplemental experimen-tation will entail investigating the structure of antennular sensillae and associated nerve clusters.
Studies in Neurobiology: Study 2: Using Heart Rate as a Bioindex to Assess Various Sensory Perceptions in Sighted and Non-sighted Crayfish
Most organisms show diversity in the type and amount of peripheral sensors that enable detection of different sensory stimuli within and across multiple sensory modalities. Variation in sensory pathways allows organisms to monitor their environment, integrate sensory information from multiple sources, and respond accordingly, due to refined integration of information. Most invertebrates possess chemosensory neurons that permit identification of environmental chemicals and are able to behave differentially between chemical compounds based upon the sensory pathway stimulated (i.e., attractive and/or repellant). Current literature shows this is particularly true for decapod crustaceans in detecting chemical signals, especially in the cephalic and thoracic appendages. Crayfish are decapod crustaceans that rely on visual and chemical cues in the environment. Behavior studies alone often exclude “fight or flight” internal readiness changes and may conclude a lack of environmental awareness. Therefore, a “sympathetic-like” autonomic response (i.e., HR, heart rate and VR, ventilation rate) in crayfish, (surface) Procambarus clarkii and (cave) Orconectes australis packardi, during chemical introduction establishes chemical and/or modality sensitivities that may be species-specific. Preliminary findings suggest crayfish that show no behavioral response display an internal response through changes in HR/VR. Specifically, crayfish show an increase in HR with attractant chemical introductions (i.e., cysteine) suggesting a natural response to potential food sources, while showing more pronounced responses to toxic/warning compounds. Future research will include using chemical stimuli identified as significant to induce electrical impulses to be recorded within antennular olfaction neurons. Supplemental experimen-tation will entail investigating the structure of antennular sensillae and associated nerve clusters.