Brain Gauge scores show improvement with treatment.
A 54 year old male was tested before and after a NUCCA correction for his C-1 vertebra being out of alignment.
Brain Gauge tests were collected before correction and 4 hours after correction. Note significant across the board improvement in all metrics, which matched the patient’s qualitative self-report on the outcome.
The next issue of corticalmetrics insights will feature a mTBI case contributed by Dr. George Roth.
Acknowledgment: Thanks to Dr. Kerry Johnson for his contribution.
Understanding mechanisms of information processing: lateral inhibition.
Lateral inhibition is the brain's way of improving contrast between adjacent or near-adjacent cortical areas. In the 1960s, Nobel prize winner Georg Von Bekesy postulated the idea of lateral inhibition. The basic idea was that when you deliver a stimulus, brain activity will be correlated with the stimulus site, and the surrounding areas will be inhibited or turned off. Long story short Von Bekesy’s predictions, which were based on sensory testing turned out to be true.
Fast forward to more modern neuroscientific techniques, and we can actually observe changes in lateral inhibition. The image at the left is a set of images that depict a slice of brain (cortex) tissue stimulated at two sites (“x” marks the spot). The dark areas are where the cortex is activated.
The difference between the conditions in the two images is that a drug has been administered on the right side that blocks inhibition. Looking at the graphs below each of the images, it is easy to see that the contrast between the two sites is lowered when the inhibition is lowered.
Sample results from an ongoing study:Amplitude Discrimination (AD) data collected from healthy controls and individuals with migraines plotted at right. (Note that smaller numbers indicate better performance) We are consistently finding that patients that are getting relief from pain demonstrate a significant shift from high AD scores to scores in the normative range.
How we measure lateral inhibition with Brain Gauge
The easiest way to tell if lateral inhibition is intact is to look at a subject's amplitude discrimination capacity. When two stimuli are simultaneously delivered, a subject will have a difficult time performing the task if lateral inhibition is below norm (which could be due to impaired GABA). The best comparison for this is sequential vs. simultaneous amplitude discrimination: lateral inhibition is maximally tasked in the simultaneous condition but not the sequential condition. If there is a significant difference between the two metrics (i.e., AD simult ADseq) then lateral inhibition is impaired.
Interested in reading further? A good description of the metrics of lateral inhibition can be found in Zhang et al, 2008
Read Zhang et al. 2008 here
Plasticity reduced with higher levels of alcohol consumption in 18-22 year olds. Summary: A study was performed on a large cohort of 18-22 year olds. Drinking behavior of the subjects was collected via interview and a number of cortical metrics tests were administered. The results demonstrated that subjects in this age group who drank more than 60 drinks per month demonstrated plasticity levels that were significantly lower than the norm. Peripherally dominated measures (i.e., those tied most closely to skin sensitivity) were not impacted but centrally mediated measures were. Plasticity is an integral part of learning and cognitive function, and speculation from this study supports the idea that excessive drinking at this age significantly impacts brain health.
For full report, see Nguyen et al, 2012
Read Nguyen et al. 2012 here
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