Neuroanatomy of Arousal

Structures

of

Importance

• pontomesencephalic reticular formation

• thalamic nuclei

  • rostral intralaminar: central lateral, paracentral, central medial nuclei

  • midline thalamic nuclei

  • ventral medial nucleus

• hypothalamus

• basal forebrain: nucleus basalis, nucleus of the diagonal band, medial septal nucleus

• cerebral cortex

Images

• reticular formation

• thalamus

• hypothalamus

• nucleus basalis

afferent: sensory pathways especially from cord; association cortex; limbic cortex; ? superior colliculi; ? cerebellum

projections to thalamic intralaminar nuclei; hypothalamus; basal forebrain

1. glutamate: pontomesencephalic reticular nuclei

2. histamine: hypothalamus (tuberomamillary nucleus)

3. acetylcholine: basal nucleus of Meynart; diagonal band nucleus; septal nuclei

References

• Neuroanatomy through Clinical Cases: Case 5.2 (p166 ff); p 859-61; p588 – 592

• Van der Werf YD, Witter MP, Groenewegen HJ; The intralaminar and midline nuclei of the thalamus. Anatomical and functional evidence for participation in processes of arousal and awareness; Brain Res Rev. 2002 Sep;39(2-3):107-40.

• Schiff, Plum. The Role of Arousal and Gating Systems in the Neurology of Impaired Consciousness; Journal of Clinical Neurophysiology 17(5): 438 - 452   (http://www.uni-tuebingen.de/cog/lehre/ss2003/seminar_bewusstsein/epapers/SchiffPlum00.pdf)

1. What thalamic nuclei are especially important for arousal of the brain?

2. List the important afferent pathways to the pontomesencephalic reticular formation.

3. What transmitters are important in cerebral arousal and where are the neurons that make them?