RESUMEN
Conspecific recognition and discrimination is a vital aspect of social interactions. Genetic manipulations have implicated the CA2 sub-field and ventral hippocampus in rodent social memory. However, little is known about the nature of hippocampal responses to social signals. We characterized ventral CA1 responses in rats while interacting with conspecifics across a gap. Many cells showed unusual "social presence responses," i.e., large elevations of firing rates, which were contingent on the presence of a conspecific. Sharp-wave ripple activity was also increased by conspecific presence. The cells were modulated by facial touch and ultrasonic vocalizations. In male rats, female conspecifics evoked stronger responses than males. In addition, responses to females differed more strongly between individual females than between males. Cells showed little response to object presence. Ventral CA1 responses were also markedly different from those of dorsal CA1, where most cells were weakly inhibited by conspecific presence.
Asunto(s)
Región CA1 Hipocampal/fisiología , Discriminación en Psicología/fisiología , Neuronas/citología , Neuronas/fisiología , Reconocimiento en Psicología/fisiología , Estimulación Acústica/psicología , Animales , Región CA1 Hipocampal/citología , Condicionamiento Clásico/fisiología , Femenino , Relaciones Interpersonales , Masculino , Memoria/fisiología , Ratas , Especificidad de la Especie , Tacto/fisiología , Vocalización Animal/fisiologíaRESUMEN
Social interactions involve multi-modal signaling. Here, we study interacting rats to investigate audio-haptic coordination and multisensory integration in the auditory cortex. We find that facial touch is associated with an increased rate of ultrasonic vocalizations, which are emitted at the whisking rate (â¼8 Hz) and preferentially initiated in the retraction phase of whisking. In a small subset of auditory cortex regular-spiking neurons, we observed excitatory and heterogeneous responses to ultrasonic vocalizations. Most fast-spiking neurons showed a stronger response to calls. Interestingly, facial touch-induced inhibition in the primary auditory cortex and off-responses after termination of touch were twofold stronger than responses to vocalizations. Further, touch modulated the responsiveness of auditory cortex neurons to ultrasonic vocalizations. In summary, facial touch during social interactions involves precisely orchestrated calling-whisking patterns. While ultrasonic vocalizations elicited a rather weak population response from the regular spikers, the modulation of neuronal responses by facial touch was remarkably strong.