It goes without saying after you read this article that watching TV and computer games etc. are brain killers when it comes to learning gemara and the like. So parents BEWARE:-)!. [At the foot of the article there were many sources of studies that confirm the facts presented here. You don't have to be a Rov in Williamsburg to appreciate the danger of TV and Internet].
From "The Biologist" by Alec Sigman
While controversy continues to surround the way the content of screen media affects our
thoughts and behaviour, a growing body of empirical evidence is indicating that watching
television causes physiological changes, and not for the better. Most of these effects occur
irrespective of the type of programme people watch – whether it is sex or violence. It is the medium, not the message. Children
aged 11 to 15 now spend 55% of their
waking lives – 53 hours a week, seven and
a half hours a day – watching TV and
computers, an increase of 40% in a decade
(BMRB, 2004). More than half of three year-olds
now have a TV set in their bedrooms.
(Rideout et al, 2003)
However, the biological sciences are fast
becoming the new arena for examining
the effects of society’s favourite pastime.
And in industrialised societies, the findings
are set to re-cast the role of the television
screen as the greatest unacknowledged
public health issue of our time.
Attention and cognition
In August 1999, the American Academy of
Pediatrics (AAP) issued guidelines recommending
that children under the age of
two watch no television or any screen
entertainment at all because television
‘can negatively affect early brain development’
and that children of all ages should
not have a television in their bedroom.
This announcement has more recently
been followed by a study of 2,500 children
(Christakis et al, 2004) published in their
journal, Pediatrics, looking at whether
early exposure to television during critical
periods of synaptic development would
be associated with subsequent attentional
problems.
About 5% of children now exhibit attention
deficit hyperactivity disorder (ADHD),
and its incidence appears to be increasing.
Although genetic inheritance accounts for
some of the prevalence of ADHD, and
despite decades of research, little thought
has gone in to the potentially crucial role
that early childhood experiences may have
on the development of attentional problems.
Christakis and his colleagues wondered
if there was an omnipresent environmental
agent that is putting some children at risk
of developing ADHD. They found that
early television exposure was associated
with attentional problems at age seven
which was consistent with a diagnosis of
ADHD. Children who watched television
at ages one and three had a significantly
increased risk of developing such attentional
problems by the time they were
seven. For every hour of television a child
watched per day, there was a 9% increase
in attentional problems. The authors suggest
that their findings may actually be an
understatement of the effects on children.
Yet attention is not merely confined to
everyday descriptions such as concentration
or attention span. New brain-imaging
studies are finding that different parts of
the brain deal with different types of
attention, and so there can be types of
attentional damage different from ADHD.
If early exposure to television does affect
aspects of attention later on, what mechanisms
may be involved?
Television elicits what Pavlov first
described as the orienting response, our
instinctive sensitivity to movement and
sudden changes in vision or sound. The
orienting response to television is apparent
almost from birth: infants, when lying on
their backs on the floor, will crane their
necks around 180 degrees to watch (Kubey
and Csikszentmihalyi, 2004). Twenty years
ago, studies began to look at whether the
medium of television alone – the stylistic
techniques of cuts, edits, zooms, pans, sudden
noises, not the content of the programme
– activates this orienting
response. By watching how electroencephalogram
(EEG) responses were
affected, Reeves et al found that these stylistic
techniques can indeed trigger involuntary
physiological responses of detecting
and attending to movement – dynamic
stimuli – something television has in
abundance. These techniques also cause us
to continue to pay attention to the screen.
Most of our stares at a television screen
are highly prone to termination, lasting
less than three seconds. But as we continue
to stare, our stare becomes progressively
less fragile gaining a powerful attentional
inertia after about 15 seconds. By increasing
the rate of edits – camera changes in
the same visual scene – one can increase
the subject’s physiological arousal along
with attention to the screen.
Modern television has increased the use
of these stylistic techniques. A study of
the pace and editing speed of Sesame
Street over 26 years observed that the
number of editing cuts on this popular
educational children’s programme actually
doubled during this period. Others have
compared the attentional demands of
children’s programmes made in the public
and private sectors, i.e. BBC and commercial
television. The duration of a typical
scene in a public children’s show lasted
over 70% longer than in a commercially
produced show. Children’s television programmes
increasingly demand constant
attentional shifts by their viewers but do
not require them to pay prolonged attentional
shifts to given events. Researchers
are now asking if it is possible that television’s
conditioning of short attentional span
may be related to some school children’s
attentional deficits in later classroom settings
and whether the recent increase of
attention deficit disorders in school age
children might be a natural reaction to our
modern speeded-up culture – an attention
deficit culture. Could it be the form, not the content, of television that is unique?
Television is the perfect medium to produce
strong rewards for paying attention
to something. Compared to the pace with
which real life unfolds and is experienced
by young children, television portrays life
with the fast-forward button fully pressed.
Rapidly changing images, scenery and
events, and high-fidelity sounds are highly
stimulating and extremely interesting.
Television is the flavour enhancer of the
audiovisual world, providing unnatural
levels of sensory stimulation. Little in real
life is comparable to this. Television may
overpay the child for paying attention to it,
and in so doing it may physically corrupt
the reward system underpinning his ability
to pay attention when the TV is off.
The actual currency used to pay off and
corrupt the reward system may come in
the form of the neurotransmitter, dopamine.
The release of dopamine in the brain is
associated with reward. In particular,
dopamine is seen as rewarding us for paying
attention, especially to things that are
novel and stimulating. Screen entertainment
causes our brain to release dopamine.
It is increasingly clear that ADHD is linked
to a change in dopamine functioning. Genes
necessary for synthesis, uptake and binding
have been implicated in ADHD, and
dopamine underfunctioning is also found
in the Spontaneously Hypertensive Rat
animal model of ADHD. This underfunctioning
of dopamine may fail to reward
the brain’s attention systems, so they do
not function effectively (Sagvolden et al,
2005). Interestingly, adults with attention
deficit disorder given dopamine-boosting
methylphenidate (Ritalin) before doing a
maths test find it easier to concentrate.
This is partly because the task seems more
interesting.
More research is needed into the extent
to which this reward system involving
dopamine (and other neurotransmitters) is
set in childhood by exposure to electronic
media such as television.
Early exposure to television is now
implicated in another childhood condition.
The very latest research from Cornell
University strongly suggests that early
childhood television viewing may be an
important trigger for autism, the incidence
of which appears to be increasing (Waldman
et al, 2006).
At the other end of the age spectrum, a
new study (Lindstrom et al, 2005) addressing
the relationships between how much
television we watch during our middle
years (20-60 yrs) and the development of
Alzheimer’s disease are concluding that
for each additional daily hour of middleadulthood
television viewing, the associated
risk of Alzheimer’s disease development
increases. Watching television was
described by the neuroscientists as a nonintellectually
stimulating activity for
brain function. A study examining the
association between soap operas, talk shows
and poorer cognition in older women found
clinically significant cognitive impairment
in all measures, including attention,
memory and psychomotor speed (Fogel and
Carlson, 2006).
While playing computer games are
thought to be more stimulating than passively
watching a soap opera, evidence
indicates that even this interactive media
is associated with limited neurological
activity. For example, a study looking at
differences in cerebral blood flow between
children playing computer games and
children doing very simple repetitive
arithmetic adding single digit numbers found that computer games only stimulated
activity in those parts of the brain
associated with vision and movement as
compared to arithmetic-stimulated brain
activity (Kawashima, 2001). Adding single
digit numbers activated areas throughout
the left and right frontal lobes. Playing
computer games did not. The findings
were described by the World Federation of
Neurology as “alarming …computer games
stunted the developing mind …”
Television viewing among children
under three years of age is found to have
deleterious effects on mathematical ability,
reading recognition and comprehension in
later childhood. Along with television viewing
displacing educational and play activities,
it is suspected this harm may be due
to the visual and auditory output from the
television actually affecting the child’s
rapidly developing brain. A 26-year study,
tracking children from birth, has recently
concluded that television viewing in childhood
and adolescence is associated with
poor educational achievement by 26 years
of age (Hancox et al, 2005). Early exposure
to television may have long-lasting adverse
consequences for educational achievement
and later socioeconomic status and wellbeing.
The authors describe a dose-response
relationship between the amount of television
watched and declining educational
performance which has ‘biological plausibility’.
Significant long-term effects
occurred even at so-called modest levels of
television viewing: between one and two
hours per day.
Sleep
An increasing number of studies have
found that children are getting less sleep
than previous generations and are experiencing
more sleeping difficulties. New
research has found a significant relationship
between exposure to television and
sleeping difficulties in different age
groups ranging from infants to adults.
A study by Thompson and Christakis
(2005) of 2068 children found that television
viewing among infants and toddlers was
associated with irregular sleep patterns.
The number of hours of television watched
per day was independently associated
with both irregular naptime schedule and
irregular bedtime schedules.
Another
study of 5-6 year olds found that both
active TV viewing and passive TV exposure
was related to shorter sleep duration,
sleeping disorders, and overall sleep disturbances.
Moreover, passive exposure to
TV of more than two hours per day was
strongly related to sleep disturbances. TV
viewing and particularly passive TV exposure
“significantly increase the risk of sleeping
difficulties” (Paavonen et al, 2006). A
study at Columbia University found that
young adolescents who watched three or
more hours of television a day ended up at
a significantly increased risk for frequent
sleep problems as adults. Remember that
this amount of screen time is actually less
than the average. On the other hand, those
adolescents who reduced their television
viewing from one hour or longer to less
than one hour per day experienced a significant
reduction in risk for subsequent
sleep problems (Johnson et al, 2004).
The implications may be serious. Stanford
University Medical Center has found evidence
that a lack of sleep can significantly
alter levels of the hormone melatonin, an
extremely powerful antioxidant. Reduced
amounts of melatonin may result in a
greater chance that cell DNA will produce
cancer-causing mutations (Sephton and
Speigel, 2003). Melatonin is also sleeppromoting.
As it grows dark melatonin
levels rise and help facilitate sleep.
Researchers have recently reported (Salti
et al, 2006) that when children aged 6-12
were deprived of their TV sets, computers
and video games, their melatonin production
increased by an average 30%.
Exposure to a television screen was associated
with lower urinary melatonin levels,
particularly affecting younger children at
a pubertal stage when important changes
in melatonin’s role take place. The lead
author speculated that girls are reaching
puberty much earlier than in the 1950s.
One reason is due to their average
increase in weight; but another may be
due to reduced levels of melatonin. Animal
studies have shown that low melatonin
levels have an important role in promoting
an early onset of puberty.
Body fat
Research from as far apart as China and
Mexico is increasingly identifying television
exposure as an independent factor in obesity.
Mexico’s health ministry has reported
that obesity has risen by 170% in a single
decade, with odds ratios of obesity 12%
higher for each hour of television watched
per day. While in China, a study of 10,000
people found that for each hour of television
viewing there was a significant
increase in the prevalence of obesity. A
study in New Zealand following children
from birth to age 15 recently found the
amount of television viewing to be a more
significant factor in obesity than the
effect sizes often reported for nutritional
Volume 54 Number 1, February 2007 Biologist 15
The impact of TV |IOB
intake and physical activity. A study of
girls aged five and nine found that even in
families where neither parent was overweight,
television was the only significant
predictor of girls’ increase in Body Mass
Index.
Beyond displacing physical activity, a new
study (Cooper et al, 2006) has reported a
significant dose-response relationship in
which REE [resting metabolic rate]
decreased as average weekly hours of TV
viewing increased. A recent study looking
at the association between television viewing
and meal frequency adds to the findings
that watching television makes both
children and adults eat significantly more,
even if they are not physically hungry.
One of the mechanisms by which television
may induce us to eat more is through
causing our brain to monitor external nonfood
cues – the television screen – as
opposed to internal food cues telling us
that we have eaten enough and can stop.
Experiments (Epstein et al, 1977) have
found that when distracted in this way
humans continue to salivate unnaturally
in response to more and more food when
normally they would not. All of these
observations occur at a time in our history
when 75% of dinners are eaten in front of
the television.
A 26-year study of the Association
Between Child and Adolescent Television
Viewing and Adult Health recently published
in The Lancet (Hancox et al, 2004),
involving 1,000 children found that children
who watched more than two hours of
television a day between the ages of five
and 15 developed significant health risks
many years later. The study concluded that
15% of cases of raised blood cholesterol,
17% of obesity, 17% of smoking and 15% of
reduced cardiovascular fitness were linked
to the television viewing that took place
years before when the adults were children.
This link remained, irrespective of other
factors such as social background, body
mass index (BMI) at age five, parents’ BMI,
parental smoking and how physically
active the children were by the age of 15.
Other biological changes strongly associated
with watching television range from
clinically increased risk of abnormal glucose
metabolism and new Type 2 diabetes
in adults, through substantial increases in
myopia, to increases in migration of cutaneous
immune system mast cells which
also “lost their granular content and the
cytoplasm shrunk”.
Conclusion
Watching television, irrespective of the
content, is increasingly associated with
unfavourable biological and cognitive
changes. These alterations occur at viewing
levels far below the population norm. Given
the population’s sheer exposure time to
this environmental factor it is more than
puzzling to consider how little awareness
and action has resulted.
Perhaps because television is not a dangerous
substance or a visibly risky activity,
it has eluded the scrutiny that other
health issues attract. Additionally, there
is little funding and public gratitude in
looking for the negative effects of the
world’s favourite pastime. Conversely,
when research is directed at identifying
what is termed ‘opportunities in the
media-rich home’ and methods to increase
so-called ‘media literacy’ or ‘visual literacy’,
encouragement and funding appear
highly forthcoming. Therefore it is hardly
surprising that the incriminating
research concerning screen media is coming
from beyond the domains of media
studies, education and psychology.
An editorial in the American Medical
Association’s Archives of Pediatric and
Adolescent Medicine now asks: “Why is it
that something that is widely recognised
as being so influential and potentially
dangerous has resulted in so little effective
action? To be sure, there has been
some lack of political will to take on the
enormously powerful and influential
entertainment industry ... [Screen] media
need to be recognised as a major public
health issue” (Christakis and
Zimmerman, 2006). So it is particularly
disconcerting to hear some academics
urging caution in interpreting these studies
and warning of the risk of over-reacting.
We must ask them, when considering
whether to expose infants and toddlers to
television, how exactly can one overreact?
What harm could result from preventing
very young children from watching
television and from reducing the
amount of television watched by those
over three years of age? Others respond
with claims that these findings do not
apply to children watching age-appropriate
or educational material. Again, this
confuses the nature of the message with
the effect of the medium and is highly
misleading. Policy makers and government
should consider these questions urgently.
The biological sciences are instrumental
in providing an alternative account of the
influence of screen media. And by ignoring
their findings we may ultimately be
responsible for the greatest health scandal
of our time.
