Wake up: The ‘Ascending reticular activating system’ (ARAS) and its role in consciousness & attention

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The reticular formation is essential for governing some of the basic functions of higher organisms and is one of the phylogenetically oldest portions of the brain.

The ascending reticular activating system (ARAS), also known as the extrathalamic control modulatory system or simply the reticular activating system (RAS), is a set of connected nuclei in the brains of vertebrates that is responsible for regulating wakefulness and sleep-wake transitions. The ARAS is a part of the reticular formation and is mostly composed of various nuclei in the thalamus and a number of dopaminergic, noradrenergic, serotonergic, histaminergic, cholinergic, and glutamatergic brain nuclei.

The ascending reticular activating system is an important enabling factor for the state of consciousness.  The ARAS also helps mediate transitions from relaxed wakefulness to periods of high attention. There is increased regional blood flow (presumably indicating an increased measure of neuronal activity) in the midbrain reticular formation (MRF) and thalamic intralaminar nuclei during tasks requiring increased alertness and attention.

The reticular formation is divided into three columns: raphe nuclei (median), gigantocellular reticular nuclei (medial zone), and parvocellular reticular nuclei (lateral zone). The raphe nuclei are the place of synthesis of the neurotransmitter serotonin, which plays an important role in mood regulation. The gigantocellular nuclei are involved in motor coordination. The parvocellular nuclei regulate exhalation.


Further References

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Plain numerical DOI: 10.1016/0149-7634(94)00043-Z
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Edlow, B. L., Takahashi, E., Wu, O., Benner, T., Dai, G., Bu, L., … Folkerth, R. D.. (2012). Neuroanatomic connectivity of the human ascending arousal system critical to consciousness and its disorders. Journal of Neuropathology and Experimental Neurology, 71(6), 531–546.

Plain numerical DOI: 10.1097/NEN.0b013e3182588293
DOI URL
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Englot, D. J., D’Haese, P. F., Konrad, P. E., Jacobs, M. L., Gore, J. C., Abou-Khalil, B. W., & Morgan, V. L.. (2017). Functional connectivity disturbances of the ascending reticular activating system in temporal lobe epilepsy. Journal of Neurology, Neurosurgery and Psychiatry, 88(11), 925–932.

Plain numerical DOI: 10.1136/jnnp-2017-315732
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Jones, B. E.. (2011). Neurobiology of waking and sleeping. Handbook of Clinical Neurology (Vol. 98)

Plain numerical DOI: 10.1016/B978-0-444-52006-7.00009-5
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Kinomura, S., Larsson, J., Gulyás, B., & Roland, P. E.. (1996). Activation by attention of the human reticular formation and thalamic intralaminar nuclei. Science, 271(5248), 512–515.

Plain numerical DOI: 10.1126/science.271.5248.512
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Yeo, S. S., Chang, P. H., & Jang, S. H.. (2013). The Ascending Reticular Activating System from Pontine Reticular Formation to the Thalamus in the Human Brain. Frontiers in Human Neuroscience, 7

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Killing babies in incubators – The fake Nayirah testimony (PR PsyOp)

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The Nayirah testimony (aka the incubator lie) is a paradigmatic case as it demonstrates how the psychology of emotions is abused in the mass-media. Psychology in action!

The whole things was a staged PsyOp by the PR firm “Hill and Knowlton”.

en.wikipedia.org/wiki/Nayirah_testimony

Darda, J.. (2017). Kicking the Vietnam Syndrome Narrative: Human Rights, the Nayirah Testimony, and the Gulf War. American Quarterly, 69(1), 71–92.

Plain numerical DOI: 10.1353/aq.2017.0004
DOI URL
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Marlin, R.. (1993). Public Relations Ethics: Ivy Lee, Hill and Knowlton, and the Gulf War. International Journal of Moral and Social Studies

Fowler, G., & Fedler, F.. (1994). A Farewell to Truth: Lies, Rumors and Propaganda as the Press Goes to War.. Florida Communication Journal