October 2011
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A recent paper by Zotev and group (citation below) has added another neurofeedback result to the several already on record. The subjects were instructed to contemplate happy memories and attempt to increased the BOLD signal from their left amygdala while real time feedback of the BOLD activity was relayed to them. Effective controls (sham feedback most importantly) were used.


What does this tell us about consciousness?


First, this type of learning uses consciousness – the feedback is explicit and so are the efforts to obtain the desired neural effects. Bio-feedback, in general, is a way of involving consciousness in controlling systems that are usually controlled unconsciously.


Secondly, the success in using the neurofeedback seems to depend somewhat in the subjects ability to bring their emotions to conscious awareness.

Across the individual subjects from the experimental group, the training effect in the left amygdala BOLD activity correlated inversely with scores on the Difficulty Identifying Feelings subscale of the Toronto Alexithymia Scale, suggesting that the better subjects rated their ability to identify their emotions, the more effectively they learned to regulate left amygdala activity via training.


Thirdly, The effect was different for the left and right amygdala. The left increased in BOLD activity while the right was only slightly raised.

Although the right amygdala showed a nominal increase in BOLD activity across the neurofeedback trials, this effect was only marginally significant. The statistically significant self-regulation was only specific to the left amygdala.

The functional difference between the left and right amygdala is probably due to their temporal dynamics.

Recent evidence from quantitative meta-analyses of functional neuroimaging studies has suggested a functional dissociation between left and right amygdala in terms of temporal dynamics, with the left amygdala involved in more detailed and elaborate stimulus evaluation and the right amygdala involved in rapid, short and relatively automatic detection of emotional stimuli… Consistent with this hypothesis, predominantly left-sided amygdala activation has been hypothesized to relate to left-lateralized higher cognitive processes associated with recognition and analytic processing and to cognitive representation of emotion.

Zotev, V., Krueger, F., Phillips, R., Alvarez, R., Simmons, W., Bellgowan, P., Drevets, W., & Bodurka, J. (2011). Self-Regulation of Amygdala Activation Using Real-Time fMRI Neurofeedback PLoS ONE, 6 (9) DOI: 10.1371/journal.pone.0024522

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