In 2006 Akgul, Akin and Sankur published an article in Med Bio Eng Comput, vol. 44:945-958, entitled “Extraction of cognitive activity-related waveforms from functional near-infrared spectroscopy signals.” The article describes a new technology to identify cognitive waveform activity. I am posting several excerpts from this article and will show its historical relevance TO THE WORK OF jOHN C. ECCLES in a subsequent post.
“the main objective of most neuroimaging studies has been the precise and accurate detection of the evoked responses to single-event trial stimulation. since the evoked responses are usually minute in amplitude, and deeply buried under the background activity of the brain, researchers have to resort to advanced signal-processing techniques to extract these evoked responses. a promising new neuroimaging modality is the functional near-infrared spectroscopy (fNIRS), which can capture cerebrovascular changes in the surface of the cortex. [This modality] can potentially detect and tract cerebrovascular changes, called blood oxygenation dependent (BOLD) signals by the use of optical methods. similar to fmri, fnirs is sensitive to deoxyhemoglobin while complimentarily it can measure the changes in oxyhemoglobin.
“. . . functional neuroimaging studies performed by both fmri and fnirs methods have confirmed that the increase of regional cerebral blood flow towards activated areas exceeds the regional oxygen consumption, and hence the signal pattern observed in the bold response resembles the oxyhemoglobin signal of fnirs. similar to fmri signal analysis, fnirs analysis is concerned with the varying cerebrovascular alterations due to stimuli. these are termed as brAIN HEMODYNAMIC RESPONSE . . . AND THEY TEND TO LAST SEVERAL SECONDS. . . . INDEPENDENT COMPONENT ANALYSIS PROVES TO BE A VIABLE SCHEME IN EXTRACTING COGNITIVE ACTIVITY-RELATED WAVEFORMS. . . . WAVEFORMS ESTIMATED BY INDEPENDENT COMPONENT ANALYSIS ARE PLAUSIBLY RELATED TO COGNITIVE ACTIVITY.”
AS THIS TECHNOLOGY ADVANCES WE HOPE TO SEE DOCUMENTED THAT THE IMMATERIAL COGNITIVE MIND GENERATES WAVEFORMS, INCLUDING GENERATION BY CREATIVE THINKING, WILL, INTENT AND ATTENTION. FOR EXAMPLE, CAN THIS TECHNOLOGY IDENTIFY THE PRECISE TEMPORAL ORIGINATION OF AN INTENT TO RAISE AN ARM?
MY NEXT BLOG WILL CITE WORK BY jOHN c. eCCLES DESCRIBED IN HIS 1994 BOOK, HOW THE SELF CONTROLS ITS BRAIN, WHICH STUDIED THE RELATION OF REGIONAL BLOOD FLOW TO THE NEURAL ACTIVITY OF ATTENTION.