Functional anatomy of intrinsic alertness: evidence for a fronto-parietal-thalamic-brainstem network in the right hemisphere

Neuropsychologia. 1999 Jun;37(7):797-805. doi: 10.1016/s0028-3932(98)00141-9.


Alertness, the most basic intensity aspect of attention, probably is a prerequisite for the more complex and capacity demanding domains of attention selectivity. Behaviorally, intrinsic alertness represents the internal (cognitive) control of wakefulness and arousal; typical tasks to assess optimal levels of intrinsic alertness are simple reaction time measurements without preceding warning stimuli. Up until now only parts of the cerebral network subserving alertness have been revealed in animal, lesion, and functional imaging studies. Here, in a 15O-butanol PET activation study in 15 right-handed young healthy male volunteers for this basic attention function we found an extended right hemisphere network including frontal (anterior cingulate-dorsolateral cortical)-inferior parietal-thalamic (pulvinar and possibly the reticular nucleus) and brainstem (ponto-mesencephalic tegmentum, possibly involving the locus coeruleus) structures, when subjects waited for and rapidly responded to a centrally presented white dot by pressing a response key with the right-hand thumb.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Analysis of Variance
  • Attention / physiology*
  • Brain / anatomy & histology*
  • Brain / physiology*
  • Brain Stem / anatomy & histology
  • Brain Stem / physiology
  • Frontal Lobe / anatomy & histology
  • Frontal Lobe / physiology
  • Humans
  • Male
  • Nerve Net / anatomy & histology
  • Nerve Net / physiology
  • Parietal Lobe / anatomy & histology
  • Parietal Lobe / physiology
  • Reaction Time
  • Reference Values
  • Signal Detection, Psychological*
  • Thalamus / anatomy & histology
  • Thalamus / physiology
  • Tomography, Emission-Computed
  • Volunteers