title: Crossmodal integration improves sensory detection thresholds in the ferret.
abstract: During the last two decades ferrets (Mustela putorius) have been established as a highly efficient animal model in different fields in neuroscience. Here we asked whether ferrets integrate sensory information according to the same principles established for other species. Since only few methods and protocols are available for behaving ferrets we developed a head-free, body-restrained approach allowing a standardized stimulation position and the utilization of the ferret's natural response behavior. We established a behavioral paradigm to test audiovisual integration in the ferret. Animals had to detect a brief auditory and/or visual stimulus presented either left or right from their midline. We first determined detection thresholds for auditory amplitude and visual contrast. In a second step, we combined both modalities and compared psychometric fits and the reaction times between all conditions. We employed Maximum Likelihood Estimation (MLE) to model bimodal psychometric curves and to investigate whether ferrets integrate modalities in an optimal manner. Furthermore, to test for a redundant signal effect we pooled the reaction times of all animals to calculate a race model. We observed that bimodal detection thresholds were reduced and reaction times were faster in the bimodal compared to unimodal conditions. The race model and MLE modeling showed that ferrets integrate modalities in a statistically optimal fashion. Taken together, the data indicate that principles of multisensory integration previously demonstrated in other species also apply to crossmodal processing in the ferret.
authors.affiliation: Dept. of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
authors.forename: Karl J
authors.initials: KJ
authors.lastname: Hollensteiner
authors.affiliation: Dept. of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Pieper
authors.affiliation: Dept. of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Engler
authors.affiliation: Dept. of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany; Institute of Cognitive Science, University of Osnabrück, 49069 Osnabrück, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: König
authors.affiliation: Dept. of Neurophysiology and Pathophysiology, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany.
authors.forename: Andreas K
authors.initials: AK
authors.lastname: Engel
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D001303:Auditory Cortex / Q000502:physiology; D001307:Auditory Perception / Q000502:physiology*; D001309:Auditory Threshold / Q000502:physiology*; D005260:Female; D005289:Ferrets / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time; D014793:Visual Cortex / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*