Bioelectromagnetisim presention
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Transcript of Bioelectromagnetisim presention
BIOELECTROMAGNETISIM
Supervisor
Dr.SADIQULLAH
Group members
Naveed Ahmad
Adil Muhammad
Subhan Ali
Dawood Khan
M.Younas khan
Umar Bin Mumtaz
First mentioned when the ancient Egyptians had problems catching a particular kind of fish(Stingray) which would give them powerful electric shocks (>450V), forcing them to drop the fish back into the water
In the first medical application of bioelectromagnetism, a similar kind of fish was used to treat headaches and arthritis from 46CE until the 17th century CE.
Definition of BEM
Discipline that examines the electric, electromagnetic, and
magnetic phenomena which arise in biological tissues. These
phenomena include
The behavior of excitable tissue (the sources)
The magnetic field at and beyond the body
The response of excitable cells to electric and magnetic field
stimulation
The intrinsic electric and magnetic properties of the tissue
Examples
Membrane potentials
Action potentials
Electric currents that
flow through
nerves/muscles
Brain Oscillations
Magnetic field of the
heart
Virtually all scientists and science
students are aware of bioelectricity
(though they may not call it that)
Not many are aware of the importance of
biomagnetism: the magnetic fields
surrounding all living organisms produced
by the internal ongoing electrical activity
Pioneered by David Cohen – 60's, 70's
SUBDIVISIONS OF BIOELECTROMAGNETISM
Maxwell's equations (the electromagnetic connection)
principle of reciprocity
Division on Theoretical Basis
The electromagnetic connection, connect
time-varying electric and magnetic fields so
that when there are bioelectric fields there
always are also Biomagnetic fields, and vice
versa (Maxwell, 1865). Depending on
whether we discuss electric, electromagnetic,
or magnetic phenomena.
The sensitivity distribution in the detection of
bioelectric signals, the energy distribution in
electric stimulation, and the sensitivity
distribution of electric impedance
measurements are the same.
SUBDIVISIONS OF BIOELECTROMAGNETISM
Division on Conceptual Basis
Bioelectricity
Bioelectromagnetism
Biomagnetism
Now these three can be subdivided into three categories
(I) Measurement of an electric or a magnetic field from a bioelectric source or
(the magnetic field from) magnetic material.
(II) Electric stimulation with an electric or a magnetic field or the magnetization
of materials (with magnetic field)
(III) Measurement of the intrinsic electric or magnetic properties of tissue.
Applications of BEM
TMS and related effects
A strong changing magnetic field can induce electrical currents in conductive tissue such
as the brain. Since the magnetic field penetrates tissue, it can be generated outside of the
head to induce currents within, causing transcranial magnetic stimulation (TMS). These
currents depolarize neurons in a selected part of the brain, leading to changes in the
patterns of neural activity. A number of scientists and clinicians are attempting to use TMS
to replace electroconvulsive therapy (ECT) to treat disorders such as severe depression.
Applications of BEM
Magnetic Stimulation of Neural Tissue
Biomagnetic field is the electric activity of biological tissue.
This bioelectric activity produces an electric current in the volume conductor which induces the
biomagnetic field.
Magnetic stimulation is a method for stimulating excitable tissue with an electric current induced by an
external time-varying magnetic field
To stimulate nerve cell by magnetism
The nerve cell require +40 mv to be stimulated. Which can be achieved by
creating magnetic field outside the body to induce current in nerve cell.
Applications of BEM
It is used for monitoring and diagnosing a variety of heart conditions.
The EEG (Electroencephalography) is a test that records the electrical activity of the brain.
It is used for monitoring and diagnosing epilepsy, sleep disorders, coma and brain-death.
Applications of BEM
Adverse effects of BEM
Thermal effects:
Most of the molecules in the human body interact weakly
with electromagnetic fields in the radio frequency or
extremely low frequency bands. One such interaction is
absorption of energy from the fields, which can cause
tissue to heat up; more intense fields will produce greater
heating. This can lead to biological effects ranging from
muscle relaxation (as produced by a diathermy device) to
burns.
Adverse effects of BEM
Behavourial effects
A research was conducted in USA on wifi effects on sleepness when
the wifi modem was turned on they did not sleep well but in the case
When the wifi modem was turned off they slept well.so from this they
concluded that EMF waves have great impact on sleeping.
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Electricity VDTs Cell phones
Before EMF
Low EMF
EMF Today
THE BASIC MECHANISM FOR THE ELECTRICAL
STIMULATION OF THE NERVOUS SYSTEM
This paper is written by F. RATTAY of TU-BioMed,
Vienna University of Technology, A-1040 Vienna,
Austria
In this paper he described that how the nervous
system can be stimulated artificialy by magnetisim.
Birds can sense and use the Earth's magnetic field to migrate to certain areas
Scientists speculate that birds have two distinct magnetic sensing mechanisms in their bodies, each
with a different function.
In birds, both of these magneto-receptors are believed to be in the head.
Wiltschkos suggested in a 2005 paper, one of the receptors probably acts as a
magnetometer - which measures magnetic intensity - and the other as a compass.
As a bird flies over them during a migration, its magnetometer may detect these anomalies and enable it
to compile a mental map of magnetic signposts for future use
The second mechanism, the compass, may indicate direction. But unlike a conventional compass, it
doesn't distinguish between north and south; it tells the bird only where a pole is and where the equator
is.