Anesthesia and Functional Connectivity: An Analysis of fMRI Changes

Summary

Functional connectivity is defined as a correlation in neural activity between distinct regions of the brain. Several recent studies have demonstrated areas of low-frequency functional connectivity inherent to brain tissue at rest. These oscillations can be measured using functional magnetic resonance imaging (fMRI) and appear to be synchronized between related areas of the brain. To date, no investigators have examined the effects of low-dose anesthesia on functional connectivity. This study will image the human brain under conditions of rest, and low-dose anesthetic induced sedation. Quality of the acquired signals will be evaluated and functional networks in the brain will be examined. Of interest is whether administration of a low-dose anesthetic disrupts functional connectivity in the brain, and whether a disruption of functional connectivity is responsible for the reported analgesic and antidepressant effects of a anesthetic. Participation in the study includes four visits: an in-person interview, an initial fMRI scan, the anesthesia infusion, and a second fMRI scan. There is an optional follow-up fMRI scan one week post infusion.

Timeline

Start

2008-02

Primary completion

2015-05

Completion

2015-05

Outcome

Outcome not reported

Stopped (Business): “Funding cessation.”

Publications

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• Background Lowe MJ, Phillips MD, Lurito JT, Mattson D, Dzemidzic M, Mathews VP. Multiple sclerosis: low-frequency temporal blood oxygen level-dependent fluctuations indicate reduced functional connectivity initial results. Radiology. 2002 Jul;224(1):184-92. doi: 10.1148/radiol.2241011005.
• Background Baliki MN, Geha PY, Apkarian AV, Chialvo DR. Beyond feeling: chronic pain hurts the brain, disrupting the default-mode network dynamics. J Neurosci. 2008 Feb 6;28(6):1398-403. doi: 10.1523/JNEUROSCI.4123-07.2008.
• Background Greicius MD, Flores BH, Menon V, Glover GH, Solvason HB, Kenna H, Reiss AL, Schatzberg AF. Resting-state functional connectivity in major depression: abnormally increased contributions from subgenual cingulate cortex and thalamus. Biol Psychiatry. 2007 Sep 1;62(5):429-37. doi: 10.1016/j.biopsych.2006.09.020. Epub 2007 Jan 8.
• Background Mayberg HS, Lozano AM, Voon V, McNeely HE, Seminowicz D, Hamani C, Schwalb JM, Kennedy SH. Deep brain stimulation for treatment-resistant depression. Neuron. 2005 Mar 3;45(5):651-60. doi: 10.1016/j.neuron.2005.02.014.
• Background Zarate CA Jr, Singh JB, Carlson PJ, Brutsche NE, Ameli R, Luckenbaugh DA, Charney DS, Manji HK. A randomized trial of an N-methyl-D-aspartate antagonist in treatment-resistant major depression. Arch Gen Psychiatry. 2006 Aug;63(8):856-64. doi: 10.1001/archpsyc.63.8.856.
• Background Woods RP, Grafton ST, Holmes CJ, Cherry SR, Mazziotta JC. Automated image registration: I. General methods and intrasubject, intramodality validation. J Comput Assist Tomogr. 1998 Jan-Feb;22(1):139-52. doi: 10.1097/00004728-199801000-00027.
• Background Tzourio-Mazoyer N, Landeau B, Papathanassiou D, Crivello F, Etard O, Delcroix N, Mazoyer B, Joliot M. Automated anatomical labeling of activations in SPM using a macroscopic anatomical parcellation of the MNI MRI single-subject brain. Neuroimage. 2002 Jan;15(1):273-89. doi: 10.1006/nimg.2001.0978.
• Background Genovese CR, Lazar NA, Nichols T. Thresholding of statistical maps in functional neuroimaging using the false discovery rate. Neuroimage. 2002 Apr;15(4):870-8. doi: 10.1006/nimg.2001.1037.
• Background Peltier SJ, Kerssens C, Hamann SB, Sebel PS, Byas-Smith M, Hu X. Functional connectivity changes with concentration of sevoflurane anesthesia. Neuroreport. 2005 Feb 28;16(3):285-8. doi: 10.1097/00001756-200502280-00017.

Drugs

Indications

No indication recorded.