concept

perturbational complexity index

Also known as: PCI

Facts (13)

Sources

Global Versus Local Theories of Consciousness and the ... link.springer.com Springer 11 facts

procedureThe perturbational complexity index (PCI) measures complexity by stimulating a localized part of the brain and assessing the global impact of that local stimulation.

claimThe perturbational complexity index (PCI) methodology has proven reliable for predicting the capacity for consciousness in awake or anesthetized participants and has produced results in the clinical assessment of unresponsive patients in a vegetative state.

claimThe Perturbational Complexity Index (PCI) is inspired by Integrated Information Theory (IIT) and was introduced as a proxy for the Φ (Phi) index, though it may be compatible with other theories such as the Global Neuronal Workspace Theory (GNWT).

claimLavazza and Massimini claim that the perturbational complexity index (PCI) method could be adapted to organoids if transcranial magnetic stimulation (TMS) and electroencephalography (EEG) were replaced with more subtle measurement tools.

claimIn the context of the Perturbational Complexity Index (PCI), consciousness is indicated by the global consequences of local stimulation, rather than local perturbations resulting from a localized stimulus.

claimIntegrated Information Theory (IIT) does not currently provide an empirically validated and uncontested methodology for measuring consciousness in humans or other systems, despite the Perturbational Complexity Index (PCI) making steps toward clinical validation.

claimWhen using the perturbational complexity index (PCI), a local perturbation in the nervous system leads to massive and unpredictable changes in the system if it is integrated, which is interpreted as a sign of consciousness; if the system is modular, the perturbation leads to only small changes in the global activity pattern.

procedureThe perturbational complexity index (PCI) methodology uses transcranial magnetic stimulation (TMS) combined with electroencephalography (EEG) recording to measure brain complexity.

claimThe 'perturbational complexity index' (PCI) is a measurement of brain complexity proposed by Massimini and colleagues that serves as a proxy for the Phi index in Integrated Information Theory.

claimThe Perturbational Complexity Index (PCI) utilizes Transcranial Magnetic Stimulation (TMS) and Electroencephalography (EEG) as its primary tools for assessing consciousness in the human brain.

referenceMichele Farisco and Jean-Pierre Changeux published an analysis regarding the compatibility between the perturbational complexity index and the global neuronal workspace theory of consciousness in 2023.

A Synergistic Workspace for Human Consciousness Revealed by ... elifesciences.org eLife 2 facts

claimThe Perturbational Complexity Index (PCI) is used to assess the brain's current state, while stimulation protocols can be adopted to directly induce transitions between states of consciousness.

claimThe Perturbational Complexity Index (PCI) is considered one of the most discriminative indices of consciousness available to date, as it measures the brain's EEG response to brief magnetic pulses.