XIX Sympozjum Srodowiskowe PTZE - materialy.pdf

XIX Sympozjum PTZE, Worliny 2009
BLOOD BRAIN BARRIER, EVOKED BRAIN WAVES
AND SCHUMANN RESONANCES
REVISITED
Andrzej J. Turski, Barbara Atamaniuk
Space Research Center, PAS, Bartycka 18A, 00-716, Warsaw, Poland
Institute of Fundamental Technological Research, PAS, Świętokrzyska 21, 00-049 Warsaw, Poland
aturski@ippt.gov.pl batama@ippt.gov.pl
The blood-brain barrier (BBB) is a metabolic or cellular structure in the central nervous
system (CNS) that restricts the passage of various chemical substances and microscopic
objects (e.g. bacteria) between the bloodstream and the neural tissue itself, while still allowing
the passage of substances essential to metabolic function (e.g. oxygen).
The blood-brain barrier has been shown to be affected by radiation in animal studies. There
is a lot of uncertainty about whether this happens in humans. There has been shown that some
biological effects are caused by EM signals of selected parameters (windows). If it did happen
it could lead to disturbances, (particularly in case of medicine and drug taking), such as
headaches, feeling tired or problems with sleeping. A study by a Swedish research group even
suggested it could lead to Alzheimer’s disease.
On the other hand there can be a problem of drugs targeting the brain. Overcoming the
difficulty of delivering therapeutic agents to specific regions of the brain presents a major
challenge to treatment of most brain disorders. In its neuroprotective role, the blood-brain
barrier functions to hinder the delivery of many potentially important diagnostic and
therapeutic agents to the brain. Therapeutic molecules and genes that might otherwise be
effective in diagnosis and therapy do not cross the BBB in adequate amounts.
Apart of the natural waves of the human brain (alpha, beta, theta and delta waves) the other
potentials can be noticed. The brain works by a series of nerve impulses, which cause
electrical signals within the brain. These signals (also called brainwaves) can be recorded
through the scalp. When a part of the body is stimulated, for instance, the eyes by a flashing
light, or the ears by a clicking sound, the brain responds to this stimulation. This response is
called an ‘evoked potential’. The response is often very small, but it can be recorded using
special techniques. Usually, we repeat each stimulus a number of times so that plenty of
responses are recorded. The computer then averages these to show how the nerve pathways
are working. There are various types of evoked potential, each with a different method of
stimulation.
• A visual evoked potential (VEP) test looks at the pathway from the optic nerve to
the part of the brain where images are interpreted and turned into pictures.
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