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Serino, A.

Publications and source records attributed to Serino, A..

2 recordsLinked to original sources

Viewing one’s body during encoding boosts episodic memory

Episodic autobiographical memories (EAMs) are recollections of contextually rich and personally relevant past events. EAM has been linked to the sense of self, allowing one to mentally travel back in subjective time and re-experience past events. However, the sense of self has recently been linked to online multisensory processing and bodily self-consciousness (BSC). It is currently unknown whether EAM depends on BSC mechanisms. Here, we used a new immersive virtual reality (VR) system that maintained the perceptual richness of life episodes and fully controlled the experimental stimuli during encoding and retrieval, including the participants body. We report that the present VR setup permits to measure recognition memory for complex and embodied 3D scenes during encoding and retrieval, that recognition memory depends on delay and number of changed elements, and that viewing ones body as part of the virtual scene (as found in BSC studies) enhances delayed retrieval. This body effect was not observed when no virtual body or a moving control object was shown. These data show that embodied views improve recognition memory for 3D life-like scenes, thereby linking the sense of self, and BSC in particular, to episodic memory and the re-experiencing of specific past events in EAM.

neuroscience

Audio-tactile and peripersonal space processing around the trunk in human parietal and temporal cortex: an intracranial EEG study

Interactions with the environment happen by the medium of the body within ones peripersonal space (PPS) - the space surrounding the body. Studies in monkey and humans have highlighted a multisensory distributed cortical network representing the PPS. However, electrophysiological evidence for a multisensory encoding of PPS in humans is lacking. Here, we recorded for the first time intracranial electroencephalography (iEEG) in humans while administering tactile stimulation (T) on the trunk, approaching auditory stimuli (A), and the combination of the two (AT). To map PPS, in AT trials, tactile stimulation was delivered when the sound was far, at an intermediate location, or close to the body. We first identified electrodes showing AT multisensory integration (i.e., AT vs. A+T): 19% of the recording electrodes. Among those electrodes, we identified those showing a PPS effect (30% of the AT electrodes), i.e., a modulation of the evoked response to AT stimulation as a function of the distance between the sound and body. For most sites, AT multisensory integration and PPS effects had similar spatiotemporal characteristics, with an early response (~50ms) in the insular cortex, and later responses (~200ms) in pre- and post-central gyri. Superior temporal cortex showed a different response pattern with AT multisensory integration at ~100ms without PPS effect. These results, representing the first iEEG delineation of PPS processing in humans, show that PPS processing happens at neural sites where also multisensory integration occurs and at similar time periods, suggesting that PPS representation (around the trunk) is based on a spatial modulation of multisensory integration.

neuroscience