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Thursday, July 14, 2016
The Michigan Daily — michigandaily.com NEWS
Study shows marijuana affects
user’s pleasure-related cognition
RESEARCH
Drug users feel less
pleasure to monetary
rewards compared to
non-users
By MADELEINE GERSON
Daily Staff Reporter
According to a recent study
conducted
by
University
of
Michigan researchers, long-term
marijuana usage is associated with
a decrease in the brain’s response
time. The study, published in
JAMA Psychiatry medical journal,
brought forth new information
about the effect marijuana can
have on the brain of a young adult
user.
Marijuana’s reputation as both a
risky gateway drug and a harmless
substance with medical benefits is
a major component in the current
legislation discussion surrounding
its
legalization.
Currently,
recreational marijuana is legal in
four states — Alaska, Colorado,
Oregon and Washington — and
Washington, D.C., and medical
marijuana is legal in 20 states.
According to an article in the
Los Angeles Times, California will
vote this November on whether to
legalize recreational marijuana.
In Michigan, medical marijuana is
legal and marijuana possession has
been decriminalized by a total of 14
cities since November 2014.
The majority of studies on long-
term marijuana usage have been
associative and limited due to
the fact that correlation does not
imply causation. Mary Heitzeg, a
University assistant professor of
psychiatry and the senior author
of the study, said her team’s study
is the first longitudinal study
about marijuana usage that is not
refutable.
“Our study is unique in that we
actually look at brain activation
measures over time as opposed to
cross-sectional studies looking at
marijuana users and non-users,”
Heitzeg
said.
“Those
studies
cannot
necessarily
disentangle
cause and effect.”
The
participants
—
108
marijuana users in their early 20s
— were asked to play a game while
their brains were being scanned in
a functional magnetic resonance
imaging scanner. In each round, the
players were informed they could
either win money for winning the
round or no money was at stake.
Dopamine is a neurotransmitter
that affects the feeling of pleasure
and
pleasure-related
cognition,
and
when
people
engage
in
rewarding
behavior,
levels
of
dopamine increase in the reward
centers of the brain — the nucleus
accumbens.
The
neuroimaging
showed
that, in participants who reported
higher usage of marijuana, less
dopamine was released. This means
marijuana users felt less pleasure in
response to the monetary rewards
presented throughout the game
compared to non-users.
On
the
contrary,
when
researchers looked at the same
participants’ responses to the
reward of drug anticipation, there
was a higher amount of dopamine
in the nucleus accumbens — which
could be a sign of addiction.
Heitzeg explained that this
could occur when a drug “hijacks”
the user’s reward system, referring
to when a user becomes dependent
on a drug to experience the feeling
of reward.
“This means that something
that would be rewarding to most
people was no longer rewarding
to them,” Heitzeg said. “This
suggests but not proves that their
reward system has been ‘hijacked’
by the drug, and that they need
the drug to feel reward — or that
their emotional response has been
dampened.”
The work of Heitzeg’s team has
led to the rise of potential future
research
questions.
Rackham
student
Meghan
Martz,
the
primary author of the study,
said
non-drug-related
rewards
other than money could produce
comparable outcomes.
“This task happens to use
monetary incentives, but there are
a number of other non-drug related
rewards that could also be tested,
such as food,” Martz said.
Martz added that the study is
relevant in today’s politics since
marijuana usage is increasing at
a high rate, which may lead to a
belief that the drug does not pose
any severe consequences to health.
“The legalization of marijuana
See MARIJUANA, Page 10
Marchers were eager to get more
people involved, encouraging many
bystanders to join the protest. Many
passing-by cars honked in support
of the protesters, and some drivers
got out of their vehicles to record
the protest.
Most bystanders either joined in
the chants or observed in silence,
but one woman, in response to
the chants of “Black lives matter!”
replied with: “All lives matter!”
The climate between protesters
and police during the protest was
friendly, with several protesters
shaking the hands of police officers
and speakers calling for the crowd
to thank the police department.
However, protest organizer Diante
Harris, a Kinesiology junior, said
the department still has work to
do build relationships with the
community.
Harris further argued that the
need for increased civilian oversight
doesnt necessarily imply the police
department has been neglecting its
responsibilities, adding that local
officers should have nothing to fear.
“The chief is probably just
thinking that this is all out of spite,
or, you know, a quick reaction, but
as people who pay these officers
to protect and serve them, and
as people that are a part of the
communities that these officers
work in, I don’t see what bad could
come out of having a say in some
of the matters,” Harris said. “Right
now the police chief doesn’t want to
hear that in Ann Arbor. He believes
that this is a local problem, and that
everyone is overreacting because of
what happened to Aura (Rosser),”
he continued, to boos from the
crowd.
In front of a crowd of hundreds
gathered on the Diag, Kinesiology
senior Nas Ali lamented the death
of Philando Castile, who was killed
on the same street Ali lived on as a
child, where his family still lives.
“Last week, when Philando
Castile passed away –– I live here, I
go to school here, but that happened
half a block from where I grew up,”
Ali said. “The cop who killed him
has pulled me over so many times,
and I can’t even put into words
the things that he has said to me.
This time it changed. As much as
I’ve grieved for everyone who has
happened before, this time I wasn’t
removed from it. It wasn’t St. Louis.
It wasn’t Florida. It was in my
backyard.”
Harris
also
spoke
to
the
experiences he’d had with police.
“Growing up, I only saw them
when someone in my community
was being arrested,” Harris said.
“What do you think that does to you
when you’re a kid, to your psyche?
You’re going to not trust the police.
You’re going to be afraid of the
police.”
Despite the distrust he described,
Harris ended by encouraging unity.
“We need more community
involvement
with
our
police
officers,” he said. “And that’s the
truth — I know not everyone wants
to hear that. A lot of people don’t
want any unity between the police
officers and the community, but
they are part of the communities
whether we like it or not. And we
are part of the communities that
they serve, whether we like it or
not.”
Protester
Johnny
Anderson
challenged
stereotypes
of
protesters, saying their message
wasn’t so unpalatable as some
believed and that demonstrators
like himself don’t condone violence.
“Everybody has this vision in
their head, that the revolution’s
going to be this violent gunfire
against the government,” Anderson
said. “No, it’s going to be peace, it’s
going to be this right here. This is
the revolution right here. CNN ain’t
coming here to see this peace, ain’t
nothing to talk about.”
Ann Arbor resident Brionne
Fonville said that the revolution
would require more than protesting
and marching.
“What I saw here tonight was
beautiful,” Fonville said. “There’s so
much power and potential in what
we did, marching. But we need to
start thinking about what we’re
going to do next. You all have the
same equal power and potential.
I’m going to paraphrase Dr. King
for a second, and all I want to say is
think about what you’re doing with
your life. Think about what you do
every day. Think about the people
you come into contact with and
think about how you can use that to
bend the moral arc towards justice.”
AAPD
Officer
Thomas
Hickey, while also encouraging
communication
between
police
and civilians, argued the AAPD has
done much to engage its community.
“I can tell you that at the Ann
Arbor Police Department, we have
been proactive about diversity and
multicultural training,” Hickey said.
“We probably go above the standard
for training. We pride ourselves on
staying current with what’s going
on, and that makes for a better
police department, and probably
overall transparent. We have great
communication with some of the
folks
here.
Communication
is
basically the bottom line.”
PROTEST
From Page 1