Bioeffects
of Selected Nonlethal Weapons - UNCLASSIFIED
Privately reported in 1998 by
the US Department of the Army
Unclassified in 2006
INTRODUCTION
INDEX
Below this line, all the text is a transcript of the original PDF
document, except for the [---comments
in
brackets like this---]
DEPARTMENT
OF THE ARMY
UNITED STATES ARMY INTELLIGENCE AND SECURITY COMMAND
FREEDOM OF INFORMATION/PRIVACY OFFICE
FORT GEORGE G. MEADE, MARYLAND 20755-5995
[Stamped
date: DEC 13 2006]
[---2006 is the year of the declassification---]
[---At the last page, you can read: "Information Cutoff Date: 17
February 1998"---]
REPLY TO:
ATTENTION OF:
Freedom of Information/
Privacy Office
Mr. Donald Friedman
Confidential Legal Correspondence
1125 Third Street
Napa, California 94559-3015
Dear Mr. Friedman:
References:
a. Your Freedom of Information Act (FOIA) request dated May 25,
2006, to the Department of the Army, Freedom of Information/Privacy Act
Division (DA FOIA/PA DIV), for all documents pertaining to the
microwave auditory effect, microwave hearing effect, Frey effect,
artificial telepathy, and/or any device/weapon which uses and./or
causes such effect; and any covert or undisclosed use of hypnosis. On
September 5, 2006, the DA FOIA/PA DIV referred a copy of your request
to this office. Yow request was received on September 11,2006.
b. Our letter of September 13, 2006, informing you of the search
for records at another element of our command and were unable to comply
with the 20-day statutory time limit in processing your request.
As noted in our letter, the search has been completed with another
element of this command and the record has been returned to this office
for our review and direct response to you.
We have completed a mandatory declassification review in accordance
with Executive Order (EO) 12958, as amended. As a result of this
review, it has been determined that the Army information no longer
warrants security classification protection and is releasable to you. A
copy of the record is enclosed for your use.
Fees for processing your request are waived.
[---PAGE 2 of the the PDF begins
after this line---]
If you have any questions concerning this action, please feel free to
contact this office at (301) 677-2308. Refer to case #614F-06.
Sincerely,
[Handwritten Signature]
Susan J. Butterfield
Director
Freedom of Information/Privacy Office
Investigative Records Repository
Enclosure
[---END
OF THE COVER LETTER---]
[---PAGE
3 of the PDF begins here---]
[---ENCLOSURE/APPENDIX BEGINS
HERE---]
[Stamped: UNCLASSIFIED]
[Strikethrough: SECRET]
[Strikethrough: NOFORN]
Bioeffects of
Selected Nonlethal Weapons (fn 1)
This addendum to the Nonlethal Technologies*Worldwide (NGIC-I
147-101-98) study addresses in summary, some of the most often asked
questions of nonlethal weapons technology, the physiological responses
observed in clinical settings of the biophysical coupling and
susceptibility of personnel to nonlethal effects weapons. These results
identify and validate some aspects of maturing nonlethal technologies
that may likely be encountered or used as nonlethal effectors in the
future including:
- Laser and other light phenomena.
- Radiofrequency directed energy.
- Aural bioeffects.
The study of electromagnetic fields and their influence on biological
systems is increasing rapidly. Much of this work is taking place
because of health concerns. For example, increased concern has arisen
regarding the effects of operator exposure to the electromagnetic
fields associated with short-wave diathermy devices, high power
microwave ovens, radar systems, magnetic resonance imaging units, etc.
In addition, much concern has arisen about extremely low frequency (60
Hz power frequency) electric and magnetic fields that originate from
high-voltage transmission lines, industrial equipment, and residential
appliances. Both occupational and residential long-term exposure have
been the focus of epidemiological studies. The studies have suggested
possible adverse effects on human health (e.9., cancer, reproduction,
etc.). Laboratory research is still being pursued to identify possible
mechanisms of interaction. However, other than thermal heating for
microwave frequencies, there is no yet agreed-upon mechanism faction.
As a co[sequence, our knowledge base is developed entirely with
phenomenological observations. Because of this fact, it is not possible
to predict how nonthermal biological effects may differ from one
exposure modality to another. It is especially difficult, because of
the small data base for fast pulses, to predict biological effects that
might be associated with high-power pulses of extremely short duration.
There is, however, a growing perception that microwave irradiation and
exposure to low frequency fields can be involved in a wide range of
biological interactions. [---PAGE
4 of the PDF begins after a few lines in the following paragraph---]
Some investigators are even beginning to describe similarities between
microwave irradiation and drugs regarding their effects on biological
systems. For example, some suggest that power density and specific
absorption rate of microwave irradiation may be thought of as analogous
to the concentration of the injection solution and the dosage of drug
administration, respectively. Clearly, the effects of microwaves on
brain tissue, chemistry, and functions arc complex and selective.
Observations of body weight and behavior revealed that ruts, exposed
under certain conditions to microwaves, eat and drink less, have
smaller body weight as a result of nonspecific stress mediated through
the central nervous system and have decreased motor activity. It has
been found that exposure of the animals to one modality of
radiofrequency electromagnetic energy substantially decreases
aggressive behavior during exposure. However, the opposite effects
of microwaves, in increasing the mobility and aggression of animals,
has
also been shown for a different exposure modality. Recent published
data implicates microwaves as a factor related to a deficit in spatial
memory function. A similar type of effect was observed with exposure to
a "resonance tuned" extremely low frequency magnetic field. Thus, the
data base is replete with phenomenological observations of biological
systems "affected" by exposure to electromagnetic energy. (The fact
that a biological system responds to an external influence does not
automatically nor easily translate to the suggestion of adverse
influence
on health.) The objective of the present study was to identify
information from this developing understanding of electromagnetic
effects
on animal systems that could be coupled with human biological
susceptibilities. Situations where the intersection of these two
domains coexist provide possibilities for use in nonlethal applications.
[---At the foot of PAGE 3 of the
PDF, the following stamp is found:---]
REGRADED UNCLASSIFIED per NGIC
ON 6 Dec 06
BY USAINSCOM FOI/PA
Auth Para 4-102 DOD 5200.IR
Incapacitating Effect:
Microwave Heating
Body heating to mimic a fever is the nature of the R.F incapacitation.
The objective is to provide heating in a very controlled way so that
the body receives nearly uniform heating and no organs are damaged.
Core temperates approximately 41º C are considered to be adequate.
At
such temperature a considerably changed demeanor will take place with
the individual. Most people, under fever conditions, become much less
aggressive; some people may become more irritable. The subjective
sensations produced by this buildup of heat are far more unpleasant
than those accompanying fever. In hyperthermia all the effector
processes are strained to the utmost, whereas in fever they are not. It
is also possible that microwave hyperthermia (even with only a 1º
C
increase in brain temperature) may disrupt working memory, thus
resulting in disorientation.
Biological
Target/Normal Functions/Disease State
The temperature of warm-blooded (homeothermic) animals like the human
remains practically unchanged although the surrounding temperature may
vary considerably. The normal human body temperature recorded from the
mouth is usually given as 37º C, with the rectal temperature one
degree
higher. Variation between individuals is typically between 35.8º C
and
37.8º C orally. Variation also occur in any one individual
throughout
the day-a difference of 1.0º C or even 2.0º C occurring
between the
maximum in the late afternoon or early evening, and the minimum between
3
and 5 o'clock in the morning. Strenuous muscular exercise causes a
temporary rise in body temperate that is proportional to the severity
of the exercise; the level may go as high as 40.0. c.
[---PAGE 5 of the PDF
begins after this paragraph---]
Extreme heat stress, such that the body's capacity for heat loss is
exceeded, causes a pathological increase in the temperature of the
body. The subjective sensations produced by this buildup of heat are
far more unpleasant than those accompanying fever. In hyperthermia all
the effector processes are stained to the utmost, whereas in fevers
they are not. The limiting temperature for survival, however, is the
same in both cases--a body temperature of 42º C. For brief
periods, people have been known to survive temperatures as high as
43º C.
In prolonged hyperthermia, with temperatures over 40º C to
41º C, the brain suffers severe damage that usually leads to
death. Periods hyperthermia are accompanied by cerebral edema that
damage neurons, and the victim exhibits disorientation, delirium, and
convulsions. This syndrome is popularly referred to as sunstroke, or
heatstroke, depending on the circumstances. When the hyperthermia is
prolonged, brain damage interferes with the central thermoregulatory
mechanisms. In particular, sweat secretion ceases, so that the
condition is further exacerbated.
Mechanism
to Produce the Desired Effects
This concept builds on about 40 years of experience with the heating
effects of microwaves. Numerous studies have been performed on animals
to identify characteristics of importance to the understanding of
energy deposition in animals. As a result of the physics, the
relationship between the size of the animal and the wavelength of the
radiofrequency energy is most important. In fact, the human exposure
guidelines to radiofrequency radiation are designed around knowledge of
the differential absorption as a function of frequency and body size.
The challenge is to minimize the time to effect while causing no
permanent injury to any organ or the total body and to optimize the
equipment function. The orientation of the incident energy with respect
to the orientation of the animal is also important.
In a study of the effect RF radiation on body temperature in the Rhesus
monkey, a frequency (225 MHz) is purposely chosen that deposits energy
deep within the body of the animal. A dose rate of 10 W/kg caused the
body temperature to increase to 42º C in a short time (10-15 min).
To avoid irreversible adverse effects, the exposure was terminated when
a temperature of 42º C was reached. A lower dose rate of 5 W/kg
caused the temperature to increase to 41.5º C in less than 2
hours. The reversible nature of this response was demonstrated by the
rapid drop in body temperature when RF exposure was terminated before a
critical temperature of 42º C was reached. It is estimated for
rats that the absorbed threshold convulsive dose lies between 22 and 35
J/g for exposure durations from less than a second to 15 minutes. For
30-minute exposure, the absorbed threshold dose for decrease in
endurance is near 20 J/g, the threshold for work stoppage approximately
9 J/g, and the threshold for work perturbation ranges from 5 to 7 J/g.
All of the above measures, except convulsions, are types of nonlethal
incapacitation. [---PAGE
6 of the PDF begins after a few lines in the following paragraph---]
A rough estimate of the power required to heat a human for this
technology is on the order of 10 W/kg given about 15 to 30 minutes of
target activation. Actual power levels depend on climatic factors,
clothing, and other considerations that affect the heat loss from the
individual concerned. A method for expressing dose rate in terms of
body surface area (i.e., watts per square meter) rather than body mass
(i.e., watts per kilogram) would permit a more reliable prediction of
thermal effects across species. However, there are large uncertainties
in the ability to extrapolate thermoregulatory effects in laboratory
animals to those in human beings.
This technology is an adaptation of technology which has been around
for many years. It is well known that microwaves can be used to heat
objects. Not only is microwave technology used to cook foods, but it is
also used as a directed source of heating in many industrial
applications. It was even the subject of the "Pound Proposal', a few
years ago in which the idea was to provide residential heating to
people, not living space. Because of the apparently safe nature of body
heating using microwave techniques, a variety of innovative uses EM
energy for human applications are being explored. The nonlethal
application would embody a highly sophisticated microwave assembly that
can be used to project microwaves in order to provide a controlled
heating of persons. This controlled heating will raise the core
temperature of the individuals to a predetermined level to mimic a high
fever with the intent of gaining a psychological/capability edge on the
enemy, while not inflicting deadly force, The concept of heating is
straightforward; the challenge is to identify and produce the correct
mix of frequencies and power levels needed to do the remote heating
while not injuring specific organs in the individuals illuminated by
the beam.
A variety of factors contribute to the attractiveness of this nonlethal
technology. First, it is based on a well-known effect, heating. Every
human is subject to the effects of heating; therefore, it would have a
predictability rating of 100%. The time to onset can probably be
engineered to between 15 and 30 minutes; however, timing is the subject
of additional research to maximize heating while minimizing adverse
effects of localized heating. the onset can be slow enough and,/or of
such frequency to be unrecognized by the person(s) being irradiated.
Safety to innocents could be enhanced by the application and additional
development of advanced sensor technologies. Incapacitation time could
be extended to almost any desired period consistent with safety. (Given
suitable R&D, temperature or other vital signs could be monitored
remotely, and temperature could be maintained at a minimum effective
point).
Time
to Onset
The time to onset is a function of the power level being used.
Carefully monitored uniform heating could probably take place in
between l5 and 30 minutes. Time to onset could be reduced but with
increased risk of adverse effects. Minimum time is dependent on the
power level of the equipment and the efficiency of the aiming device.
Duration
of Effect
Assuming that the heating is done carefully, reversal of elevated body
temperature would begin as soon as the source of heat is removed.
[---PAGE 7 of the PDF begins
after this paragraph---]
Tunability
This concept is tunable in that any rate of heating, up to the maximum
capacity of the source, may be obtained. Thus it is suitable for use in
a gradual force or "rheostatic" approach. If the situation allows, and
the source is sufficiently powerful, there is the possibility to use
this technology in a lethal mode as well. Prolonged body temperature
above 43' C is almost certain to result in permanent damage to the
brain and death.
Distribution
of Human Sensitivities to Desired Effects
No reason has been identified to suggest that anyone would be immune to
this technology. Individuals with compromised thermoregulatory
mechanisms would be susceptible with a lower incident energy density.
This would include people with organic damage to the hypothalamus, the
part of the brain that integrates the autonomic mechanisms which
control heat loss as well as people with compromised somatic features
of heat loss (e.g., respiration, water balance, etc.).
The technologies needed for the thermal technology concept are
relatively well developed because of the known biophysical mechanism,
the universal susceptibility of humans to the mechanism of heating, and
because of a well developed technology base for the production of
radiofrequency radiation. Because the human body is inhomogeneous,
certain organs are, by virtue of their size and geometry, more easily
coupled with one radiofrequency wavelength than another. Therefore,to
avoid permanent damage to the suspect or to innocent bystanders, it
maybe necessary to vary the frequency to avoid localized heating and
consequent damage to any organ, Additionally, it will be necessary to
avoid the conditions thought to be associated with the induction of
cataracts. Thus, while the technology of microwave heating in general
is mature, adaptation as a nonlethal technology will require
sophisticated biophysical calculations k) identify the proper regimen
of microwave frequencies and intensities; it will also be necessary to
optimize existing hardware to meet the biophysical requirements.
Possible
Influence or Subject(s)
If the technology functions approximately as envisioned, the targeted
individual could be incapacitated within l5 to 30 minutes. Because this
technology is focused on a relatively slow onset, it should only be
used in situations where speed is not important. The very uncomfortable
nature oaf high body temperature may be useful in negotiations or
possibly for controlling crowds. It would be equally useful on single
persons or crowds. Evidence also indicates a disruption of working
memory thus disorientation may occur because fall inability to
consolidate memory of the recent (minutes) past. [---PAGE 8 of the PDF begins after a
few lines in the following paragraph---]
Technological
Status of Generator/Aiming Device
Equipment needed to explore this concept in the laboratory is available
today. Design and construction of the RF/microwave generator will
depend on the constraints posed by the calculations, potential
generation devices, and energy-directing structures. A variety of
options exist for both of these equipment needs. The use of advanced
frequency and modulation-agile RF generation and amplification
circuitry will be required to assess fully the frequency/power/time
envelope of RF heating profiles required. Although much equipment is
commercially available, it is likely that custom hardware and software
will be necessary because available equipment has not been designed
with the need for frequency/intensity variability, which w.ill probably
be needed for safety purposes. In addition, the design of antennas and
other energy-directing structures will almost certainly involve unique
configurations. Since this technology utilizes radiofrequency energy,
it can be defeated by the use of shielding provided by conductive
barriers like metal or metal screen.
[Back to Index]
Incapacitating Effect:
Microwave Hearing
Microwave hearing is a phenomenon, described by human observers. as.
the sensations of buzzing, ticking, hissing, or knocking sounds that
originate within or immediately behind the head. There is no sound
propagating through the air like normal sound. This technology in its
crudes! form could be used to distract individuals; if refined. it
could also be used to communicate with hostages or hostage taken
directly by Morse code or other message systems, possibly even by voice
communication.
Biological
Target/Normal Functions/Disease
State This technology makes use of a phenomenon first described in the
literature over 30 years ago. Different types of sounds were heard
depending on the particulars of the pulse characteristics. Various
experiments were performed on humans and laboratory animals exploring
the origin of this phenomenon. At this time, virtually all
investigators who have studied the phenomenon now accept thermoelastic
expansion of the brain,-the pressure wave of which is received and
processed by the cochlear microphonic system, to be the mechanism of
acoustic perception of short pulses of RF energy. One study (in 1975)
using human volunteers, identified the threshold energy of
microwave-auditory responses in humans as a function of pulse width for
2450 MHz radiofrequency energy. it is also found that about 40 J/cm2
incident energy density per pulse was required.
Mechanism
to Produce the Desired Effects
After the phenomenon was discovered, several mechanisms were suggested
to explain the hearing of pulsed RF fields. Thermoelastic expansion
within the brain in response to RF pulses was first studied and
demonstrated in inert materials and was proposed as the mechanism of
hearing of pulsed RF fields. A pressure wave is generated in most solid
and liquid materials by a pulse of RF energy--a pressure wave that is
several orders of magnitude larger in amplitude than that resulting
from radiation pressure or from electrostictive forces. The
characteristics of the field-induced cochlear microphonic in guinea
pigs and cats. the relationship of pulse duration and threshold,
physical measurements in water and in tissue-simulating materials, as
well as numerous theoretical calculations-all point to thermoelastic
expansion as the mechanism of the hearing phenomenon. [---PAGE 9 of the PDF begins after
this paragraph---]
Scientists have determined the threshold energy level for human
observers exposed to pulsed 2450-MHz fields (0.5-to 32 micron pulse
widths). They found that, regardless of the peak of the power density
and the pulse width, the per-pulse threshold for a normal subject is
near 20 mJ/kg. The average elevation of brain temperature associated
with
a just-perceptible pulse was estimated to be about 5x10-6º
C.
Time
to Onset
The physical nature of this thermoelastic expansion dictates that the
sounds are heard as the individual pulses are absorbed. Thus, the
effect is immediate (within milliseconds). Humans have been exposed to
R.F energy that resulted in the production of sounds.
Duration
of Effect
Microwave hearing lasts only as long as the exposure. There is no
residual effect after cessation of RF energy.
Tunability
The phenomenon is tunable in that the characteristic sounds and
intensities of those sounds depend on the characteristics of the RF
energy as delivered. Because the frequency of the sound heard is
dependent on the pulse characteristic of the RF energy, it seems
possible that this technology could be developed to the point where
words could be transmitted to be heard like the spoken word, except
that
it could only be heard within a person's head. In one experiment,
communication of the words from one to ten using "speech modulated"
microwave energy was successfully demonstrated. Microphones next to the
person experiencing the voice could not pick up the sound. Additional
development of this would open up a wide range of possibilities.
Distribution
of Human Sensitivities to Desired Effects
Because the phenomenon acts directly on cochlear precesses, the
thermoelastic pressure waves produce sounds of varying frequency. Many
of
the tests run to evaluate the phenomenon produced sounds in the 5 kHz
range and higher. Because humans are known to experience a wide range
of hearing loss due to cochlear damage, it is possible that some people
can hear RF induced sounds that others with high frequency hearing
loss cannot. Thus, there is a likely range of sensitivity, primarily
based on the type of pulse and the condition of the cochlea. Bilateral
destruction of the cochlea has been demonstrated to abolish all
RF-induced auditory stimuli.
Recovery/Safety
Humans have been subjected to this phenomenon for many years. The
energy deposition required to produce this effect is so small that it
is not considered hazardous experimentation when investigating
responses at the just-perceptible levels. [---PAGE 10 of the PDF begins after
this paragraph---]
Possible
Influence on Subject(s)
Application of the microwave hearing technology could facilitate a
private message transmission. It may be useful to provide a disruptive
condition to a person not aware of the technology. Not only might it be
disruptive to the sense of hearing, it could be psychologically
devastating if one suddenly heard "voices within one's head. "
Technological
Status of Generator/Aiming Device
This technology requires no extrapolation to estimate its usefulness.
Microwave energy can be applied at a distance, and the appropriate
technology can be adapted from existing radar units. Aiming devices
likewise are available but for special circumstances which require
extreme specificity, there may be a need for additional development.
Extreme directional specificity would be required to transmit a message
to a single hostage surrounded by his captors. Signals can be
transmitted long distances (hundreds of meters) using current
technology. Longer distances and more sophisticated signal types will
require more bulky equipment, but it seems possible to transmit some
the of signals at closer ranges using man-potable equipment.
Range
The effective range could be hundreds of meters.
[Back to Index]
Incapacitating Effect:
Disruption of Neural Control
The nature of the incapacitation is a rhythmic-activity synchronization
of brain neurons that disrupts normal cortical control of the
corticospinal and corticobulbar pathways; this disrupts normal
functioning of the spinal motor neurons which control muscle
contraction and body movements. Persons suffering from this condition
lose voluntary control of their body. This synchronization may be
accompanied by a sudden loss of consciousness and intense muscle spasms.
Biological
Target/Normal Functions/Disease State
The normal function of the brain is to control all forms of behavior,
voluntary control of body, and the homeostatic parameters of the
organism. In normal conditions, all the brain structures, neuron
populations, networks, and single units function with specific rhythmic
activity depending on the incoming sensory information, information
from mnemonic structures, and signals from visceral organs. Each single
neuron provides specific processing of information it receives and
forms a specific pattern of impulse firing as outgoing information.
Synchronization of neuron activity is a natural mechanism of the brain
function that uses such controlling processes as motivation, attention
and memory (experience) in order to organize behavior. For example,
motivational processes are considered as activating ascending signals
that synchronize the neuron activity of specific brain structures and
neuron networks; this activation/synchronization in turn activates
specific forms of behavior such as sexual, aggressive, ingestive
activities. [---PAGE 11
of the PDF begins after this paragraph---]
In normal functioning the degree of neuronal synchronization is highly
controlled. From experiments that record the neuronal activity in
different brain areas simultaneously in animals, it is known that
correlation of spike activity between neurons (measured bl the
correlation level of synchronization) changes depending on the stage of
behavior, motivation, attention, or activation of the memory processes.
However, under some conditions, such as physical stress, heat shock, or
strong emotional stress, the level of synchronization may become
higher, involving nonspecific large populations of brain neurons and
the synchronization may become uncontrollable.
Depending on at which frequency the synchronization rhythm occurs and
how many neurons are involved, it may produce different physical
effects; muscle weakness, involuntary muscle contractions, loss of
consciousness, or intense (tonic) muscle spasms. The higher level of
synchronization takes place in persons affected with epilepsy when they
experience periodic seizures since they have a pathologic source (e.g.,
from injury to the brain) of rhythmic synchronization. Because the
neurophysiological mechanisms of epiteptiform synchronization are
better documented, this incapacitating technology is described in terms
of epileptogenesis.
The neurophysiological mechanisms active in epileptogenesis involve
changes in membrane conductances and neurotransmitter alterations as
they affect neuronal interaction. In the process of epileptogenesis,
either some neurons arc discharging too easily because of alterations
in membrane conductances or there is a failure inhibitory
neurotransmission. The actual discharges have been recognized to result
from a neuronal depolarization shift with electrical synchrony in cell
populations related in part to changes in membrane conductances. The
ionic basis and biochemical substrate of this activation have been
areas of considerable study but still leave many questions unanswered.
What are the basic cellular properties, present in normal cells and
tissue, that could contribute to the generation of abnormal activity?
What parts of the systems are low threshold and function as trigger
elements?
One of the current hypotheses is involved with microcircuitry,
particularly local synaptic interactions in neocortical and limbic
system structures. In the hippocampus, the role of the trigger element
has been long attributed to the CA3 pyramidal cells - a hypothesis
based on the fact that spontaneous synchronous burst discharge can be
established in CA3 neurons Some studies describe an intrinsically
bursting -e[ type in the neocortex that plays a role similar to that of
CA3 cells in the hippocampus and that of deep cells in the pyriform
cortex. The intrinsic nature of these cells appears to be all important
contributor to the establishment of synchronized bursting in these
regions. Another apparent requirement in such a population is for a
certain degree of synaptic interaction among neurons, such that
discharge of even one cell enlists the activity of its neighbors. Given
the presence of these bursting cells and the occurrence of excitatory
interactions among them in normal tissue, it may actually be the
morphologic substrate for epileptiform discharges. [---PAGE 12 of the PDF begins after
a few lines in the following paragraph---]
Another hypothesis has focused particularly on the role of
N-methyl-D-aspartate (NMDA) receptors. Various factors regulate the
efficacy of NMDA receptors: their voltage-dependent blockade by
magnesium and modulation by glycine and polyamines. For example, in the
low magnesium model, spontaneous synchronous burst discharge in
hippocampal pyramidal cell populations is sensitive to NMDA
antagonists. That finding suggests that it is the opening of NMDA
channels, by relieving the magnesium blockade, that facilitates
epileptiform activity.
Significant attention in the literature is also being given to
gamma-amino butyric acid (GABA) receptors for the potential role in
control of excitability. Changes in GABA inhibitory efficacy can lead
to important effects on the excitability of the system. GABAergic
inhibitory post-synaptic potentials (lPSPs) have been shown to be quite
labile in response to repetitive activation of cortical cell
populations, as may occur during epileptiform discharge. Scientists
have shown that even a small percentage change in GABA inhibition can
have profound effects on neocortical epileptogenesis. These changes in
CABAergic inhibition may be the key to an explanation of how repetitive
discharge patterns give rise to ictal discharge. Further, there appears
to be a significant increase in excitatory postsynaptic potential
(EPSP) frequency prior to seizure initiation an observation that is
consistent with loss of IPSP efficacy prior to ictal onset.
The above hypotheses describe different mechanisms of epileptogenesis,
but it is quite possible that all of these mechanisms take place, and
they reflect large variety of types of epileptic seizures. The common
principle of the mechanisms proposed is the change of membrane
properties (i.e., conductance, permeability etc.) of certain neurons
which results in depolarization and burst discharging. Some factors
(e,g., trauma) can affect these specific neurons and initiate synchrony
for neurons that control internal communication and communication with
various muscle systems not associated with vital functions (i.e., head
beating, breathing). High strength pulsed electric fields could also be
such a factor.
Mechanism
to Reproduce the Desired Effects
Application of electromagnetic pulses is also a conceptual nonlethal
technology that uses electromagnetic energy to induce neural synchrony
and disruption of voluntary muscle control. The effectiveness of this
concept has not been demonstrated. However, from past work in
evaluating the potential for electromagnetic pulse generators to affect
humans, it is estimated that sufficiently strong internal fields can be
generated within the brain to trigger neurons. Estimates are that 50 to
100 kV/m free field of very sharp pulses (~ -1 nS) are required to
produce a cell membranic potential of approximately 2 V; this would
probably be sufficient to trigger neurons or make them more susceptible
to firing. [---PAGE 13
of the PDF begins in the middle the following paragraph---]
The electromagnetic pulse concept is one in which a very fast
(nanosecond time frame) high voltage (approximately 100 kV/m or
greater) electromagnetic pulse is repeated at the alpha brain wave
frequency (about l5 Hz). It is known that a similar frequency of
pulsing light can trigger sensitive individuals (those with some degree
of light-sensitivity epilepsy) into a seizure and it is thought that by
using a method that could actually trigger nerve synapses directly with
an electrical field essentially 100% of individuals would be
susceptible to seizure induction. The photic-induced seizure phenomenon
was borne out demonstrably on December 16, 1997 on Japanese television
when hundreds of viewers of a popular cartoon show were treated,
inadvertently, to photic seizure induction (figure 31). The
photic-induced seizure is indirect in that the eye must receive and
transmit the impulses which initially activate a portion of the brain
associated with the optic nerve. From that point the excitability
spreads to other portions of the brain. With the electromagnetic
concept, excitation is directly on the brain, and all regions are
excited concurrently. The onset of synchrony and disruption of muscular
control is anticipated to be nearly instantaneous. Recovery times are
expected to be consistent with, or more rapid than, that which is
observed in epileptic seizures.
Time
to Onset
No experimental evidence is available for this concept. However,
light-induced seizures latency onset in photosensitive epileptics
varies from 0.1 to about l0 seconds. Because of the fact that the
electrical impulses triggered by light must spread to other parts of
the brain, photic-induced seizures are expected to have a generally
slower onset than neural synchrony induced by high-strength pulsed
electric fields.
Duration of Effect
For epileptic individuals, the typical duration of a petit mal event or
a psychomotor event is 1 minute or 2, possibly longer, while the
duration of a grand mal seizure is 1 to 5 minutes. In a non-epileptic
individual who is induced by electromagnetic means, the durations of
the different events are expected to be roughly the same as the
epileptic individual's events after the external excitation is removed.
Tunability
There are many degrees of epileptic seizure in diseased persons, and it
seems reasonable that electromagnetic stimulation of neural synchrony
might be tunable with regard to type and degree of bodily influence,
depending on the parameters associated with the chosen stimulus.
Because there are no actual data to build on, these statements must be
considered tentative. It is known that in the study of photic-induced
seizures, parameters can be varied so that the individual under study
does not actually undergo a grand mal seizure. This knowledge gives
confidence that the proposed technology would be tunable.
Distribution
of Human Sensitivities to Desired Effects
It is anticipated that 100% of the population would be susceptible. The
mechanism is one that could act on many individual neuronal cells
concurrently and hence does not depend on spreading regions of
electrical activity as in the disease state. [---PAGE 14 of the PDF begins after
a few lines in the following paragraph---]
Possible
Influence on Subjects(s)
If the technology functions approximately as envisioned, the targeted
individual could be incapacitated very quickly. Because there have been
no reported studies using the I\ conditions specified, experimental
work is required to characterize onset time. Different types of
technologies could be employed to influence wide areas or single
individuals. Because this technology is considered to be tunable, the
influence on subjects could vary from mild disruption of concentration
to muscle spasms and loss of consciousness. The subject(s) would have
varying degrees of voluntary control depending on the chosen degree of
incapacitation.
Technological
Status of Generator/Aiming Device
An electric field strength of roughly 100 Kv/m over a time period of 1
nanosecond is approximately the condition thought to be necessary to
produce the desired effect when provided to an overall repetition rate
of 15 Hz. Such a field may be developed using a radarlike,
high-peak-power, pulsed source or an electromagnetic pulse generator
operated at 15 Hz. These technologies exist today sufficient to
evaluate the disabling concept. Power requirements are not high because
the duty factor is so low. Aiming devices are currently available, but
a high degree of directionality at long distances will require
development, It may be necessary to provide bursts of these nanosecond
pulses in order to stimulate the desired effect. As the duty time
increases so does the average power requirement for power source,
Because there were no open literature reports from which to make
inferences, there is some uncertainty about the power levels required.
Range
The effective range could be hundreds of meters.
Defeat
Capabilities/Limitations
Shielding can be provided by conductive barriers like metal or metal
screen. There arc a number of drugs that are capable of inducing
convulsive seizures and others, like phenobarbital, diphenyllhydantoin,
trimethadione, 2-4 dinitrophenol, and acetazolamide, which are
anticonvulsive. Anticolvulsive drugs are known to be helpful in
reducing the effect of seizures in epileptic patients, but their
ability to reduce the effect of the proposed technology is unknown
(possibly no effect) but expected to be less than for photic- induced
seizures.
[Back to Index]
Incapacitating Effect: Acoustic Energy
The nature of the incapacitation consists of severe pressure
sensations, nystagnus (a spasmodic, involuntary motion of the eyes),
and nausea caused by high intensities of 9140-155 dB). Nystagmus occurs
when convection currents are produced (cupula movement) in the lateral
ear canal. This cupula movement causes the eyes to move involuntarily;
hence, the external world is interpreted as moving. The subject "sees"
his surroundings turning round him and at the same time experiences a
sensation of turning. Persons exposed to these levels of sound
experience nausea. [---PAGE
15 of the PDF begins after the heading of the following paragraph---]
Biological
Target/Normal Functions/Disease State
The two lateral semicircular canals, one located in each inner ear,
alert a person to the fact that his upright head is experiencing
angular acceleration. Within the ampulla of the canal are several so
called hair cells. The cilia of these cells protrude into the lumen of
the ampulla where they are encased in a mass of jelly-like material
(the cupula) which is attached to the opposite wall of the canal. As
the head accelerates, the cilia arc bent by an inertial force of the
cupula and the viscous liquid in the canal lumen. The bending of the
cilia excites hair cells which in tum excite afferent neurons; these
then alert the brain that a change of position of the head has
occurred. Similar events occur when the head stops moving. The result
of a strong hair cell stimulus to the brain is a rapid eye movement,
call nystagmus, a feeling of dizziness and disorientation, and a
possibility of nausea and vomiting.
Normal hearing is in the range between the frequencies of20,000 to
16,000 Hz with the optimal sensitivity for most people between the
frequencies of 500 to 6000 Hz.
Mechanism
to Produce the Desired Effects
Because the end organs for acoustic and vestibular perception are so
closely related, intense acoustic stimulation can result in vestibular
effects. The hypothesis is that the sound of normal intensity produces
oscillations of the endolymph and perilymph, compensated for by
oscillations of the round window. High intensity sound produces eddy
currents, which are localized rotational fluid displacements. High
intensity sound can also produce nonlinear displacement of the stapes,
causing a volume displacement, the result of which can be a fluid void
in the labyrinth. To fill the void, fluid may be displaced along the
endolymphatic duct and/or block capillary pathways, which, in tum,
could stimulate vestibular receptors. Stimulation of the vestibular
receptors may lead to nausea and vomiting if the sound pressure level
is high enough. Conclude that both eddy currents and volume
displacement serve to stimulate vestibular receptors in humans, when
exposed to high levels of noise.
One study found nystagmum in guinea pigs exposed to high levels of
infrasound via stimulation of the vestibular receptors. However, the
same lab was unable to produce nystagmus in human subjects at 5- and
10-second exposures to a pure tone at 135 dB, broadband engine noise,
or a I 00 Hz tone at I 20 dB, pulsed three times/s or 2 minutes. The
same research was unable to elicit nystagmus at levels up to 155 dB,
and also equally unable to produce nystagmus using infrasound levels of
I l2-150 dB in guinea pigs, monkeys, and humans. However, research with
audible components in the sound spectrum with guinea pigs and monkeys
produced nystagmus. Other researchers report other vestibular effects
in addition to nystagmus at the following thresholds: 125 dB from
200-500 Hz, 140 dB at 1000 Hz, and 155 dB at 200 Hz. Decrements in
vestibular function occur consistently for broadband noise levels of
140 dB (with hearing protection). [---PAGE 16 of the PDF begins after
a few lines in the following paragraph---]
Human subjects listened to very high levels of low-frequency noise and
infrasound in the protected or unprotected modes. Two-minute duration
as high as 140 to 155 dB produced a range of effects from mild
discomfort to severe pressure sensations, nausea, gagging, and
giddiness. Effects also included blurred vision and visual field
distortions in some exposure conditions. The nature and degree of all
effects was dependent on both sound level and frequency with the most
severe effects occurring in the audible frequency range (as opposed to
infrasound), at levels above about 145 dB. The investigators found no
temporary threshold shift (TTS) among their subjects, and the use of
hearing protection greatly alleviated the adverse effects.
Since the early days of jet-engine testing and maintenance, anecdotal
evidence has appeared linking exposure to intense noise, with such
complaints as dizziness, vertigo, nausea, and vomiting. As a result of
siren noise at 140 dB, subjects consistently reported a feeling of
being pushed sideways, usually away from the exposed ear, and one
subject reported difficulty standing on one foot.
These effects were not as dramatic as from the jet engine (broadband)
noise at 140 dB. This research concludes that the threshold of
labyrinthine dysfunction is about 135 to 140 dB and that these effects
occur during, but not after, exposure.
Time
to Onset
No times to onset of nausea or nystagmus were identified in the
literature but is presumed to be relatively immediate based on effects
to the labyrinth system occurring during, but not after, exposure to
sound pressure levels of 135 to 140 dB.
Duration
of Effect
The incapacitation la6ts only as long as the incapacitating sound is
present.
Tunability
Based on the data presented above, it is unclear whether the degree of
nausea or nystagmus is tunable, but similar symptoms caused by other
stimuli a.re variable in degree.
Distribution
of Human Sensitivities to Desired Effects
It is most probable that all individuals will be susceptible to this
stimulus with the exception of those with a disease or defect (i.e.,
deaf mutes) of some part or parts of the vestibular system. Data showed
no consistent decrease in vestibulo-ocular reflects with increased
age. [---PAGE 17 of the
PDF begins in the middle the following paragraph---]
Recovery/Safety
Normal subjects are likely to recover immediately and experience no or
unmeasurable changes in hearing unless well known
frequency-intensity-time factors are exceeded. This is based on studies
which found no temporary threshold shift in hearing of subjects tested
at low frequency. Occupational safety personnel generally recognize
that 115 dB(A) is to be avoided and that 70 dB(A) is assumed safe. Is
believed that the noise energy with predominating frequencies above 500
Hz have a greater potential for hearing loss than noise energy at lower
frequencies. Occupational standards for noise state that a person may
be exposed continuously for 8 hours to 90 dB(A) or 1 5 minutes to 115
dB(A).
Possible
Influence on Subject(s)
Induction of nystagmus and nausea will have variable effects on
individuals. Effects may be sufficiently incapacitation to allow
offensive advantage; the perception of sickness may make a subject
susceptible to persuasion. It would be difficult to target single
individuals at the present level of sound directing technology. This
technology may be better suited for groups of people.
Technological
Status of Generator/Aiming Device
Sound generating technology is well developed but not highly portable.
Aiming devices are poorly developed.
Range
Under normal circumstances the sound pressure level decreases 6 dB(A)
when the distance from the source is doubled. For example if the sound
is 100 dB(A) at 100 It, at 200 ft the sound would be 94 dB(A). At very
high sound levels, certain conditions may lead to nonlinear effects in
propagation and greatly increase range accuracy.
Defeat
Capabilities/Limitations
Negative effects of audible sound are greatly decreased if hearing
protection is worn. High frequency sound is more easily blocked than
low frequency sou[d due to wavelength effects.
[Back to Index]
Laser-Induced
Biological Effects
There are three basic damage mechanisms associated with exposure to
laser radiation: chemical, thermal, and mechanical or
acoustic-mechanical.
The laser-induced, chemical alterations in irradiated tissue are
referred to as photochemical damage. The likelihood of laser radiation
in the blue-light portion of the electromagnetic spectrum (.380 to .550
microns) inducing photochemical reactions progressively decreases with
increasing wavelength. Photochemical effects are not observed upon
exposure to radiation with wavelengths exceeding .550 to .650 microns
because the kinetic energy associated with these photons is
insufficient to initiate a photochemical change. [---PAGE 18 of the PDF begins after
this paragraph---]
On the other hand, the thermal effect is a primary mechanism for
laser-induced injury. The extent of the injuries induced depends upon
the wavelength and energy of the incident radiation, duration of
exposure, and the nature of the exposed tissue and its absorption
characteristics. Generally, this mechanism predominates in the visible
and the near-infrared (.760 to 1.4 microns) portions of the
electromagnetic spectrum and for almost all CW and pulsed exposures
between 0.1 milliseconds and I to 5 seconds.
The third injury mechanism associated with exposure to laser radiation
is the mechanical or acoustical-mechanical effect. The radiant energy
is absorbed into the tissue and, as a result of rapid thermal expansion
following a short (l nanosecond to 0.1 millisecond) laser radiation
pulse, a pressure wave is generated that may result in explosive tissue
injury.
Generally, all three mechanisms operate concurrently in an irradiated
animal. Thermal effects currently predominate for continuous wave (CW)
lasers, while mechanical effects are of increased significance for
pulsed-mode lasers. With even higher power, one must also consider
nonlinear phenomena such as multiphoton absorption and electromagnetic
field effects.
The organs most susceptible to external laser radiation are the skin
and eyes. The severity of injury is affected by the nature of the
target, the energy density delivered to the target, the frequency and
power of the laser, atmospheric attenuation of the beam, and the use of
filtering or amplifying optics by the target, etc.
The primary effect on the skin is thermal damage (bums). The severity
varies from slight erythema or reddening to severe blistering or
charring, depending on such factors as total energy deposition, skin
pigmentation, and the tissue,s ability to dissipate heat.
The eye is particularly susceptible to intense pulse of laser radiation
because of its unique sensitivity to light. The focusing effect is
similar to that of a magnifying lens, which focuses the energy on a
particular spot. Since the cornea and lens of the eye amplify the
intensity of the light incident upon the retina, the retina is
extremely sensitive to visible and near-infrared light, and damage to
the retina may result in temporary or permanent loss of visual acuity.
Laser eye injuries vary according to incident power, spot size, beam
angle, temporal mode (CW or pulsed), and pulse repetition frequency.
Reported effects include corneal lesions, bums, cataracts, and retinal
lesions.
Some high-power lasers can cause antipersonnel effects by the
deposition of thermal energy. These lasers must operate at a wavelength
that is readily absorbed by the skin or the cornea. These generally
include the far- and mid-IR regions (10 to 12 microns and 3 to 5
microns) as well as the ultraviolet region (<0.4 microns). However.
ultraviolet wavelengths generally do not propagate well in the
atmosphere, so the primary threat wavelengths to be considered are
between 3 and l2 microns. Although relatively modest amounts of far-IR
laser power are required to produce superficial bums on the skin at
short ranges, and efforts to design rheostatically lethal laser weapons
are on going. [---PAGE
19 of the PDF begins after this paragraph---]
Nonlethal blinding laser weapons generally use collimated beams with
very low beam divergence, and the energy contained in the beam
diminishes relatively slowly over great distances. Imaging systems such
as eyes and EO vision systems have focusing optics that bring the
incident plane wave of light to focus at the sensor plane. This results
in a high optical gain (greater than 100,000 for eyes), which makes the
associated sensor vulnerable to relatively low fluences of laser energy.
The effects of lasers on eyes are threefold:
- Dazzling or induced g1are.
- Flashblinding or loss of night adaptation.
- Permanent or semipermanent blinding.
The severity of laser eye injuries varies according to the incident
power, spot size, beam angle, pupil diameter (ambient light
conditions), temporal mode (CW or pulsed), and PRF of the laser.
Reported effects include corneal bums, cataracts (a permanent
cloudiness of the lens), and retinal bums and perforations. Low-energy
laser weapons arc capable of causing the latter.
Exposure to relatively low laser energies can produce temporary changes
in the ability to see without producing permanent injury. Exposure to
laser light can produce an effect called glare or dazzle, which is
similar to the temporary loss of vision experience when viewing the
headlights of an oncoming car. The visual effects last only as long as
the light is present in the field of view (FOV). At slightly higher
energy exposures, the same laser radiation can saturate or flashblind
the photoreceptor cells, resulting in after images that fade with time
after exposure. Only visible radiation will induce veiling glare or
after images; near-IR radiation will not produce these effects even
though the radiant energy reaches the photoreceptor cells.
Flashblindness and dazzle, while not permanent injuries, can cause
discomfort and temporary loss of vision. Some studies have shown that
dazzle and flashblindness can seriously impact mission performance,
especially in highly visual tasks such as piloting an aircraft or
aiming.
Blinding is the permanent or semipermanent loss of visual acuity. The
effect can last from several hours onward and generally is evidenced by
a dark spot in the field of vision. This spot is called a scotoma. The
impact of the scotoma on visual acuity will vary with the size and
position of the injury. Human vision is greatly affected when the laser
damage is to the central vision area of the retina called the fovea.
Nonfoveal laser damage may be less severe or even go unnoticed because
it affects only the peripheral vision. The most serious retinal
injuries occur when the incident light is so intense that a perforation
in the retina is formed, resulting in a hemorrhage into either the
subretinal layer or, in the most severe cases, the vitreous humor of
the eve. Less severe exposures result in lesions on the retina.
[Back to Index]
Footnote: 1-(U) This appendix
is classified FOR OFFICIAL USE ONLY in its entirety.
[---PAGE 20 of the PDF begins
here---]
Information Cutoff Date: 17 February
1998
[Strikethrough: Derived
from: Multiple sources]
[Strikethrough: Declassify
on: Source marked "OADR"]
[Strikethrough: Date
of Source: 17 February 1998]
[---At the foot of PAGE 20 of the
PDF, the following stamp is found:---]
REGRADED UNCLASSIFIED per NGIC
ON 6 Dec 06
BY USAINSCOM FOI/PA
Auth Para 4-102 DOD 5200.IR
[Back to Index]