Neuropsychologia
August 28, 2013
Keisuke Suzuki, Sarah N. Garfinkel, Hugo Critchley et al.
491 citations
Identifying with a body is central to being a conscious self. The classic rubber hand illusion shows that body-ownership can be modulated by timing visual and tactile feedback, and its strength relates to individual differences in sensitivity to internal bodily signals (interoception). Here, an innovative cardiac rubber hand illusion using augmented reality and feedback of cardiac information demonstrates that both subjective and objective measures of virtual-hand ownership are enhanced by cardio-visual feedback in-time with the actual heartbeat compared to asynchronous feedback. These measures correlate with interoceptive sensitivity and are also modulated by integrating proprioceptive signals via real-time visual remapping of finger movements. Interoceptive signals directly influence body ownership through multisensory integration, supporting models of conscious selfhood based on interoceptive predictive coding.
Cognitive Neuropsychiatry
February 27, 2018
Geoff Davies, Charlotte L. Rae, Sarah N. Garfinkel et al.
23 citations
People in the early stages of psychosis show a reduced ability to accurately evaluate their own perceptions, a metacognitive deficit. In a perceptual decision-making task, individuals with first-episode psychosis performed worse on metacognitive accuracy than healthy controls, even when their basic perceptual performance was accounted for. Grey matter volume was also reduced in the superior frontal gyrus, a brain region linked to metacognition. However, no direct relationship was found between grey matter volume and metacognitive accuracy, leaving the neural basis of this deficit unclear. These findings suggest that a specific problem in scrutinizing one's own perceptions may underlie later functional difficulties in schizophrenia.
bioRxiv (Cold Spring Harbor Laboratory)
November 9, 2023
Fernando E. Rosas, Pedro A. M. Mediano, Christopher Timmermann et al.
14 citations
preprint
Autonomic signals can reveal aspects of subjective and neural states. A Bayesian framework estimated heart rate entropy under psychedelics. Across four drugs—LSD, DMT, psilocybin, and ketamine—mean heart rate, high-frequency heart rate variability, and heart rate entropy consistently increased during the psychedelic experience. These changes predicted various dimensions of the experience. Heart rate entropy increases correlated with brain entropy increases, while other autonomic markers did not. Cost-efficient autonomic measures can reveal detail about subjective and brain states, opening new research avenues in neuroscience.