IFIBYNE   05513
INSTITUTO DE FISIOLOGIA, BIOLOGIA MOLECULAR Y NEUROCIENCIAS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Discrete uni- and multimodal mechanisms control sensorimotor gating of goldfish startle
Autor/es:
CURTIN, PAUL C.; COHEN, SAMANTHA S.; MEDAN, VIOLETA; KARAPETYAN, SHUSHANIK; NEUMEISTER, HEIKE; PREUSS, THOMAS
Lugar:
College Park, Maryland
Reunión:
Congreso; Tenth International Congress of Neuroethology; 2012
Institución organizadora:
International Society for Neuroethology
Resumen:
Sensorimotor gating mechanisms regulate the integration of sensory
information in decision-making motor systems. These effects can be
quantified in pre-pulse inhibition (PPI) paradigms, wherein weak
(subthreshold prepulse) stimuli are used to modify the response to
subsequent strong (suprathreshold pulse) stimuli presented short
(20-1000 ms) intervals apart. Importantly, although PPI can be activated
by visual and/or auditory prepulse stimuli, the mechanisms that
integrate multiple afferent modalities are largely unknown. Here, we
applied multi-modal PPI paradigms to study the integration of visual and
auditory sensory modalities in the startle behavior of goldfish, and
recorded soma-dendritic integration in the decision-making neuron
(Mauthner cell) that triggers the behavior. Preliminary results indicate
two main effects. First, the sequential order of stimulus modalities
determines the sensorimotor gating effects evoked by pre-pulse stimuli.
Auditory pre-pulse stimuli typically evoke attenuation of both visual
and auditory startle responses. Visual pre-pulses, however, evoke
inhibition of visual startle responses, but facilitate auditory startle
responses. Secondly, our results show that the salience of visual
pre-pulse stimuli is also an important determinant of sensorimotor
gating effects. We tested this by comparing prepulse-gating effects
evoked by flashes of light and by projected images of rapidly expanding
discs (i.e., looming stimuli). We found that whereas light-flash
prepulses evoke inhibition of the startle response, looming
visual-prepulse stimuli evoke the opposite, a facilitation of startle.
In sum, these findings suggest that plasticity in sensorimotor gating is
driven by discrete uni- and multimodal mechanisms. Functionally, the
sequence and kind of stimuli likely have biological relevance for
adaptive behavioral decisions.