**7. Conclusions**

The near infrared spectroscopy (NIRS) is a powerful non-invasive method that probes brain oxygenation. The subject is of great interest to researchers and the medical profession, resulting in many clinical, neuroscience and physiology of exercise studies and publications. NIRS is a noninvasive and easy to handle method, and will provide a new direction for functional mapping.

We have verified that breathing may affect to great extent the brain physiology. With breathing exercises the arterial CO2 can be increased, which in turn increases CBF and brain oxygenation.

the EtCO2 periodic pattern and the corresponding HEG periodic pattern is depicted by their multiplication. The power spectra are normalized to unity. Maximal correlation is achieved

Fig. 6. The correlation between the power spectra of the EtCO2 periodic pattern and the corresponding HEG periodic pattern is depicted by their multiplication. The power spectra are normalized to unity. Maximal correlation is achieved when the multiplication is equal to

The near infrared spectroscopy (NIRS) is a powerful non-invasive method that probes brain oxygenation. The subject is of great interest to researchers and the medical profession, resulting in many clinical, neuroscience and physiology of exercise studies and publications. NIRS is a noninvasive and easy to handle method, and will provide a new direction for

We have verified that breathing may affect to great extent the brain physiology. With breathing exercises the arterial CO2 can be increased, which in turn increases CBF and brain

when the multiplication is equal to one.

one.

**7. Conclusions** 

functional mapping.

oxygenation.

The most important finding of our experiments is the periodic correlation between respiration, oxygenation and blood volume changes. The results clearly show a periodic change of cerebral oxygenation with the same period as the breathing exercises, indicating that with each breath the brain oxygenation was periodically changing. Similar periodic changes in blood volume indicate that the brain pulsates with a frequency of respiration.

Present results were achieved by using very slow breathing patterns with the INVOS Cerebral Oximeter (ICO). If the present ICO devices will be modified to allow sampling of rSO2 at frequencies higher than the frequency of normal respiration and higher than the heart rate, it will be possible to observe new types of brain waveforms. These waveforms may have new information about brain oxygenation, cognitive function, brain pulsation and brain motion. Under these circumstances it will be possible to understand much better the correlations between respiration and brain physiology. The sampling of rSO2 should go up to, or preferably above 4 Hz. The accuracy of the reading device also should be changed from 2 significant digits to 3 digits. We believe that these changes will enable new explorations and new insights on the influence of respiration on brain's physiology. The HEG, which does not measure directly the rSO2 can serve this purpose by using Eq. (3), which determines the ratios of rSO2. The difference between the ICO and the HEG is that the ICO penetrates dipper into the brain, while the HEG penetrates only the surface near the probe. The ICO results are more stable and are related to larger volumes in the brain.

Neurodegenerative diseases are characterized by low CBF, in our research we have found effective ways to increase CBF. We will continue our research in order to explore the possibilities of increased CBF and its influences on intellectual abilities and on fighting degenerative diseases. Devices displaying the oxygenation periodic waveforms should be developed for new diagnostic and research purposes.

Our method to obtain the above results is through the use of human subjects. This is a new avenue in approaching the study of CBF, brain oxygenation, improving the cognitive function and especially in view of the growing elderly population.

Our three methods used in simple execises can be used on the general population, are noninvasive, without the use of pharmaceuticals and have no side effects. They differ from each other in that the breathing affects mostly the global blood flow, arithmetic problem solving and biofeedback affects the regional blood flow (in our case the Fp1 region).

Both our theoretical and experimental work differs from other studies due the specific instrumentation and our experimental procedure. Most of the results came close to our expectation.

We concluded that breathing can be used effectively to control CBF by the ventilatory control of end tidal CO2. This research may have implications for complementary diagnosis and treatment of conditions involving regional cerebral metabolism such as cerebral vascular ischemia, seizures disorders, stroke, Alzheimer's disease, and more. Following that thought could lead us to improved cognitive function through a higher supply of oxygen to specific regions of the brain.

We foresee future more detailed investigations to be made in the area of the effect of CO2 on specific regions of the brain. This would be of great interest because a higher CO2 supply

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**9** 

**Comparison of Cortical Activation During Real** 

**Rehabilitation by Mental Imaginary of Walking** 

Non-invasive brain imaging technologies have become an increasingly important part of research in neurosciences. The thirst for information about brain function is universal, and imaging of the human brain has been used by many as a medium for the discussion. So far, Functional brain imaging with positron emission tomography (PET), functional magnetic resonance imaging (fMRI), electroencephalographic (EEG), and Magnetoencephalography (MEG) have greatly increased scientists' ability to study localized brain activity in humans and carry out studies for better understanding of the neural basis of mental states. They have been used extensively to map regional changes in brain activity, not only in neuroscience researches, as well as in social sciences to objectively and quantitatively evaluate psychological problems. PET and fMRI are based on changes in local circulation and metabolism (Raichle & Mintun, 2006). PET produces detailed three-dimensional images of certain processes in the brain by detecting gamma rays emitted indirectly by radioactive material which has been injected into the person's blood stream prior to scanning. fMRI produces high quality pictures of the brain's delicate soft tissue structures using strong magnets and pulses of radio waves to manipulate the natural magnetic properties of hydrogen, creating useful images of organs and soft tissues. MEG and EEG image electrical activity in the brain. MEG measures magnetic fields generated by small electrical currents in neurons of the brain using arrays of SQUIDs (superconducting quantum interference devices). EEG uses multiple electrodes fixed to the person's scalp to measure the dynamic pattern of electrical fields in the brain. In cognitive neuroscience, researchers use EEG technology to study event-related potentials (ERPs)—brain measurements that are

These methods provide information about changes in electrical, hemodynamic and metabolic activities. Each of these techniques has its advantages and disadvantages, but

**1. Introduction** 

associated with a response to a stimulus.

**Walking and Mental Imagery of Walking –** 

**The Possibility of Quickening Walking** 

Kenji Ishida2, Takeshi Ando3 and Masakatsu G. Fujie3

Jiang Yinlai1, Shuoyu Wang1, Renpeng Tan1,

*1Kochi University of Technology* 

*2Kochi University 3Waseda University* 

*Japan* 

*Neurotherapy* 8(3), pp 5-21 and In: Tinius T. (Ed.) *New Developments in Blood Flow Hemoencephalography*, Haworth Medical Press, pp 5-21.

