Abstract :
We propose a model for interhemispheric (IH) communication through the callosum, based on previous computer analysis of electric (EEG) and magnetic (MEG) recordings. Intralaminar oscillators, producing a synchronic front-occipital sweep in each hemisphere of 12.5 ms, improve the use of the callosal fibers by time multiplex, coincident-redundant multiplexing and “tuning” between homologous regions. It permits IH sampling from integration zones, phase modulation (PM) with respect to a periodic (or referenced) spikes, coding by the shape of the action potential and sensitivity to tiny electrical variations. It is postulated that the intralaminar complex is part of a set of parallel chains of oscillators in nested loops (“cascade control”) through the nervous system, swept by different waves such as, for instance, a motor-sensory wave. These chains could be closed at different levels as in REM sleep and awake state. Phase lags in the chain permit “periodic sensitivity” and decoding of collective signals for specific neurons. Reduction of resonance in Alzheimer´s disease has been reported during MEG. Hence, synchronization pathologies caused by unilateral lesions, result in “cross talk”, lack of access to working memory and hallucinosis
Keywords :
biocontrol; bioelectric potentials; brain models; cascade control; electroencephalography; magnetoencephalography; medical signal processing; neurophysiology; phase modulation; physiological models; 12.5 ms; EEG; MEG; action potential; callosal fibers; cascade control; homologous regions; integration zones; interhemispheric communication; intralaminar complex; intralaminar oscillators; motor-sensory wave; nervous system; nested loops; parallel oscillator chains; periodic spikes; phase lags; phase modulation; synchronic front-occipital sweep; synchronization pathologies; thalamic electric oscillator; time multiplex coincident-redundant multiplexing; Brain modeling; Control systems; Electroencephalography; Magnetic analysis; Magnetic recording; Optical fiber communication; Oscillators; Phase modulation; Sampling methods; Shape;