Dopamine replacement therapy (DRT) alleviates motor symptoms in Parkinson’s disease (PD) but can trigger hallucinations in a subset of patients, yet the neural basis of this selective vulnerability is unknown. Hallucinations are among the most disabling non-motor symptoms of PD, linked to social isolation, dementia and institutionalization. Using a validated robotic paradigm to induce and...
Abstract Objectives Regular self-compassion practice is associated with improved mental health by fostering kindness toward one’s suffering and relying on self-related processes like perspective-taking. It is not known whether recently described self-related processes that rely on multisensory bodily signals, induced by exposing participants to an avatar and multisensory stimulation, also...
medRxivJuly 10, 2026Lada Kohoutová, Jevita Potheegadoo, Léa F Duong Phan Thanh et al.
preprint
Background: Hallucinations, ranging from minor (MH) to structured, are a common non-motor symptom in Parkinson's disease (PD). Structured hallucinations have been associated with altered functional connectivity (FC) between dorsal/ventral attention (DAN, VAN) and default mode (DMN) networks. As structured hallucinations are linked to rapid cognitive decline and MH are often viewed as their...
Nonduality is a foundational but conceptually elusive notion across several contemplative traditions. Nondual traditions challenge the assumption that a subject-object structure characteristic of ordinary experience is an intrinsic feature of conscious awareness. However, little remains known about the neurocognitive mechanisms associated with such experiential state. Here, we investigated how...
CortexOctober 2025Nathalie H Meyer, Mariana Babo-Rebelo, Jevita Potheegadoo et al.
Episodic autobiographical memory (EAM) is a building block of self-consciousness, involving recollection and subjective re-experiencing of personal past experiences. Any life episode is originally encoded by a subject within a body. This raises the possibility that memory encoding is shaped by bodily self-consciousness (BSC), a basic form of self-consciousness arising from the multisensory and...
Brain and SpineAugust 1, 2025Abdullah Al Awadhi, Daniel Kiss-Bodolay, S. Grannò et al.
Introduction The preservation of the human self—a fundamental yet underexplored aspect of neurosurgical practice—has gained increasing attention in recent years. Research question How can neural correlates of self-consciousness be identified, monitored, and protected during brain tumor surgery, and how might this reshape the concept of “onco-functional balance”? Material and methods This review...
Experienced meditation practitioners often report altered states of their sense of self, including decentering and distancing the self from the body and one's current concerns. Altered states of the sense of self, such as disembodiment and distancing of the self from the body, have also been induced experimentally using virtual reality (VR) and linked neurally to heartbeat-evoked potentials...
Abstract Serotonergic psychedelics alter self-boundaries and can induce out-of-body experiences (OBEs)—the sense of being located outside one’s physical body. While OBEs also occur in clinical conditions and can be experimentally induced, their neural basis under psychedelics remains underexplored. In an open-label, baseline-controlled MRI study of 62 healthy adults administered psilocybin, we...
Subcortical brain structures such as the subthalamic nucleus or the thalamus are involved in regulating motor and cognitive behavior. However, their contribution to perceptual consciousness remains unclear, due to the inherent difficulties of recording subcortical neuronal activity in humans. Here, we asked neurological patients undergoing surgery for deep brain stimulation to detect weak...
Out-of-body experiences (OBEs) are characterized by the subjective experience of being located outside the physical body. Little is known about the neurophysiology of spontaneous OBEs, which are often reported by healthy individuals as occurring during states of reduced vigilance, particularly in proximity to or during sleep (sleep-related OBEs). In this paper, we review the current state of...
Grid cells in the entorhinal cortex (EC) encode an individual's location in space, integrating both environmental and multisensory bodily cues. Notably, body-derived signals are also primary signals for the sense of self. While studies have demonstrated that continuous application of visuo-tactile bodily stimuli can induce perceptual shifts in self-location, it remains unexplored whether these...
Inducing hallucinations under controlled experimental conditions in non-hallucinating individuals represents a novel research avenue oriented toward understanding complex hallucinatory phenomena, avoiding confounds observed in patients. Auditory-verbal hallucinations (AVH) are one of the most common and distressing psychotic symptoms, whose etiology remains largely unknown. Two prominent...
Out-of-body experiences (OBEs) are characterized by the subjective feeling of being located outside one's physical body and perceiving one's own body from an elevated perspective looking downwards. OBEs have been correlated with abnormal integration of bodily signals, including visual and vestibular information. In two studies, we used mixed reality combined with a motion platform to manipulate...
Out-of body experiences (OBEs) are characterized by the subjective experience of being located outside the physical body. Evidence supports that OBEs triggered by electrical stimulation and epileptic seizures are associated with disrupted brain activity in a distributed network centred at the temporo-parietal junction and the resulting multisensory disruption of body representation. However,...
Abstract Grid cells in entorhinal cortex (EC) encode an individual’s location in space and rely on environmental cues and multisensory bodily cues. Body-derived signals are also primary signals for the sense of self as the continuous application of visuo-tactile bodily stimuli elicits illusory drifts in perceived self-location. It is unknown whether illusory changes in self-location are...
A growing number of studies have focused on identifying cognitive processes that are modulated by interoceptive signals, particularly in relation to the respiratory or cardiac cycle. Considering the fundamental role of interoception in bodily self-consciousness, we here investigated whether interoceptive signals also impact self-voice perception. We applied an interactive, robotic paradigm...
Breathing is peculiar among autonomic functions through several characteristics. It generates a very rich afferent traffic from an array of structures belonging to the respiratory system to various areas of the brain. It is intimately associated with bodily movements. It bears particular relationships with consciousness as its efferent motor control can be automatic or voluntary. In this review...
A fundamental scientific question concerns the neural basis of perceptual consciousness and perceptual monitoring resulting from the processing of sensory events. Although recent studies identified neurons reflecting stimulus visibility, their functional role remains unknown. Here, we show that perceptual consciousness and monitoring involve evidence accumulation. We recorded single-neuron...
Adopting the perspective of another person is an important aspect of social cognition and has been shown to depend on multisensory signals from one's own body. Recent work suggests that interoceptive signals not only contribute to own-body perception and self-consciousness, but also to empathy. Here we investigated if social cognition - in particular adopting the perspective of another person -...
Autoscopic phenomena (AP) are illusory own body reduplications characterized by the visual perception of a second own body in extrapersonal space, and include three main forms: autoscopic hallucination (AH), heautoscopy (HAS) and out-of-body-experience (OBE). Past research showed that lesions were heterogeneously distributed and affected many different brain regions within and across patients,...
Episodic memory (EM) is classically conceived as a memory for events, localized in space and time, and characterized by autonoetic consciousness (ANC) allowing to mentally travel back in time and subjectively relive an event. Building on recent evidence that the first-person visual co-perception of one's own body during encoding impacts EM, we used a scene recognition task in immersive virtual...
Abstract Previous studies investigated bodily self‐consciousness (BSC) by experimentally exposing subjects to multisensory conflicts (i.e., visuo‐tactile, audio‐tactile, visuo‐cardiac) in virtual reality (VR) that involve the participant's torso in a paradigm known as the full‐body illusion (FBI). Using a modified FBI paradigm, we found that synchrony of visuo‐respiratory stimulation (i.e., a...
Neural evidence suggests that mechanisms associated with conscious access (i.e., the ability to report on a conscious state) are "all-or-none". Upon crossing some threshold, neural signals are globally broadcast throughout the brain and allow conscious reports. However, whether subjective experience (phenomenal consciousness) is categorical (i.e., transitioning abruptly from unconscious to...
Although recent studies on self-consciousness emphasized the importance of bodily processing and multisensory integration, such research has focused solely on bodily signals originating from the outside of the body (i.e., exteroceptive bodily signals) or internal bodily signals from visceral organs (i.e., interoceptive bodily signals) and how each system contributes to self-consciousness,...
Nightmares are characterized by the experience of strong negative emotions occurring mainly during REM sleep. Some people suffer from nightmare disorder, which is defined by the repeated occurrence of nightmares and by significant distress in wakefulness. Yet, whether frequent nightmares relate to a general increase in emotional reactivity or arousal during sleep remains unclear. To address...