Brain Shows Transition Between Conscious and Unconscious State, Using functional Electrical Impedance Tomography

The BBC News website, reporting on results presented at the European Anaesthesiology Congress in Amsterdam on June 14th, show a  tomographic video of a  patient loosing consciousness following the administration of anesthesia.

Below are some still images from the video which give an idea of the changes that take place.  The images are indirect measures of  neural firing in the brain and hence have a very high resolution time.  The device resembles an EEG more than an MRI device both in terms of cost and size.



This is the latest development of EIT technology from Manchester University, which hosted an international meeting in 2009 entitled International Conference on Biomedical Applications of Electrical Impedance Tomography (EIT).

The technology used is described in further detail in a published paper which is available as a downloadable PDF file, “fEITER – a new EIT instrument for functional brain imaging” by J L Davidson, P Wright, S T Ahsan, R L Robinson, C J D Pomfrett & H McCann.

Further links to this technology may be found <here> and below:


[1] Tidswell A T, Gibson R H, Bayford and D S Holder 2001 Three-dimensional electrical impedance tomography of human brain activity Neuroimage 13 283-294

[2] Gilad O and Holder D S 2009 Impedance changes recorded with scalp electrodes during visual evoked responses: implications for EIT of fast neural activity Neuroimage 47 514-522

[3] McCann H et al 2006 Sub-second functional imaging by Electrical Impedance Tomography in Proc. of 28th Annual Int. Conf. of the IEEE EMBS (New York City, NY, USA) 4269-4272

[4] Polydorides N, Lionheart W R B and McCann H 2002 Krylov subspace iterative techniques: on detection of brain activity with electrical impedance tomography IEEE Trans. Med. Imag., 21 596-603

[5] Rafiei-Naeini M and McCann H 2008 Low-noise current excitation sub-system for medical EIT Physiol. Meas. 29(6) S173-S184

[6] Davidson J L et al 2009 fEITER – a new instrument for OR and ICU applications in Proc. of 10th International Conference on Biomedical Applications of Electrical Impedance Tomography (Manchester,UK) Available:

[7] Sirotin Y B et al 2009 Spatiotemporal precision and hemodynamic mechanism of optical point spreads in alert primates Proc. Natl. Acad. Sci. 106(43) 18390-18395


About Robert Fields

This entry was posted in Uncategorized. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s