Elsevier

NeuroImage

Volume 17, Issue 2, October 2002, Pages 1080-1086
NeuroImage

Rapid Communication
Reflective Self-Awareness and Conscious States: PET Evidence for a Common Midline Parietofrontal Core

https://doi.org/10.1006/nimg.2002.1230Get rights and content

Abstract

A recent meta-analysis has shown precuneus, angular gyri, anterior cingulate gyri, and adjacent structures to be highly metabolically active in support of resting consciousness. We hypothesize that these regions constitute a functional network of reflective self-awareness thought to be a core function of consciousness. Seven normal volunteers were asked to think intensely on how they would describe the personality traits and physical appearance of themselves and a neutral reference person known to all the subjects (the Danish Queen). During each of the four conditions cerebral blood flow distribution was measured by the intravenous H215O PET scanning technique. During scanning, no sensory or motor activity was intended. After each scan, the subjects reported the contents of their thoughts during the scan to ascertain that the instructions had been followed. The results confirmed our hypothesis: Statistical parametric mapping showed differential activity in precuneus and angular gyri during reflection on own personality traits and in anterior cingulate gyri during reflection on own physical traits. Connectivity analysis of synchrony showed these regions to be functionally connected during reflective self-awareness. The commonality between the neural networks of the resting conscious state and self-awareness reflects the phenomenological concept of a fundamental contribution of reflective self-awareness to the contents and coherence of the conscious state.

References (36)

  • S.J. Blakemore et al.

    Why can't you tickle yourself?

    NeuroReport

    (2000)
  • A.R. Braun et al.

    Dissociated pattern of activity in visual cortices and their projections during human rapid eye movement sleep

    Science

    (1998)
  • P. Fiset et al.

    Brain mechanisms of propofol-induced loss of consciousness in humans: A positron emission tomographic study

    J. Neurosci.

    (1999)
  • R.S.J. Frackowiak et al.

    Human Brain Function

    (1997)
  • K.J. Friston et al.

    Comparing functional (PET) images: The assessment of significant change

    J. Cereb. Blood Flow Metab.

    (1991)
  • C.D. Frith et al.

    Willed action and the prefrontal cortex in man: A study with PET

    Proc. R. Soc. London B

    (1991)
  • D.A. Gusnard et al.

    Searching for a baseline: Functional imaging and the resting human brain

    Nat. Rev. Neurosci.

    (2001)
  • Cited by (0)

    1

    Present address: Department of Clinical Neurophysiology, NF3063, Rigshospitalet University Hospital, DK-2100 Denmark.

    2

    Present address: Department of Clinical Physiology, Bispebjerg Hospital, DK-2400 Copenhagen, Denmark.

    3

    Present address: PET-Center, Aarhus University Hospital, DK-8000 Aarhus, Denmark.

    View full text