Injections Temporarily Turn Slacker Monkeys Into Model Workers

[Guest guest]

Maybe 60 - 70 hours in a workweek isn't enough. ;-)

 

> SSRI-Research

> Fri, 13 Aug 2004 23:19:12 -0400

> [sSRI-Research] Injections Temporarily Turn

> Slacker Monkeys Into Model Workers

>

>

> [--they never stop............. ;-( ]

>

>

> Injections Temporarily Turn Slacker Monkeys Into

> Model Workers

>

>

http://story.news./news?tmpl=story & u=/latimests/injectionstemporarilytu\

rnslackermonkeysintomodelworkers

>

> Thu Aug 12, 7:55 AM

>

> By Alan Zarembo Times Staff Writer

>

> Laboratory monkeys that started out as careless

> procrastinators became

> super-efficient workers after injections into their

> brains that suppressed a

> gene linked to their ability to anticipate a reward.

>

> The monkeys, which had been taught a computer game

> that rewarded them with

> drops of water and juice, lost their slacker ways

> and worked faster while

> making fewer errors.

>

> Government researchers used a new technique to

> temporarily block a gene,

> known as D2, that normally produces receptors for

> the brain chemical

> dopamine - a component in the perception of pleasure

> and satisfaction.

>

> Terrence Sejnowski, a neurobiologist at the Salk

> Institute for Biological

> Studies in La Jolla, called the experiment a " tour

> de force " for opening a

> new way of modulating brain chemistry. " The ability

> to block a specific type

> of receptor in a specific part of the brain could

> allow a new generation of

> therapeutics with fewer side effects, " he said.

>

> The results, reported Tuesday in the Proceedings of

> the National Academy of

> Sciences (news - web sites), could also shed light

> on mental illnesses that

> involve motivation, such as obsessive compulsive

> disorder and mania.

>

> It turns out that the work ethic of rhesus monkeys

> resembles that of many

> humans.

>

> " If the reward is not immediate, you procrastinate, "

> said Barry Richmond, a

> neurologist who led the study at the National

> Institute of Mental Health.

>

> The task at hand was a computer game in which a

> monkey, perched in a

> plexiglass cage in front of a computer monitor,

> would release a lever each

> time a red dot on the screen turned green. Only

> quick responses counted.

>

> The number of successes needed for a reward varied -

> one, two or three. A

> gray bar on the monitor told the seven monkeys in

> the experiment of their

> progress, brightening as a drink became imminent.

> Before their genetic treatment, the monkeys in the

> test dawdled when the

> gray bar was dim. Only when it glowed did they

> become conscientious.

>

> All that changed after a snippet of DNA known as an

> " anti-sense expression

> vector " was injected into a part of the brain known

> as the rhinal cortex.

> The vector suppressed the expression of the D2 gene

> for several weeks,

> hampering the ability of the rhinal cortex to detect

> dopamine.

>

> The monkeys no longer understood the meaning of the

> gray bars. As a result,

> their interest never waned. They worked their levers

> like obsessed gamblers,

> never knowing when the jackpot would be delivered.

> They stopped only after

> their thirst was quenched.

>

> To the researchers, the results made sense.

>

> Dopamine is related to the reward pathways in the

> brain. The rhinal cortex

> is a part of the brain where meaning is attached to

> recognized objects. The

> hardworking monkeys acted as if their rhinal

> cortexes had been removed.

>

> But don't expect any gene-suppressing injections for

> chatty office workers

> or inattentive students.

> " Perhaps they would look like manic people all the

> time, " Richmond said.

>

> The research could help in understanding the neural

> circuitry in people who

> have any of a variety of disorders.

>

> Schizophrenia and Parkinson's disease (news - web

> sites) are related to

> dopamine pathways.

>

> Other illnesses are linked to some fault in the

> reward circuitry of the

> brain. Manic people work even when the rewards are

> insignificant. In

> depression, no amount of work seems worth the

> reward. In obsessive

> compulsive disorder, the rewards never seem to

> register. Drug abusers risk

> danger for their reward.

>

> The research also advances the use of the vector

> technique, which had been

> used before in mice but never in primates.

>

> Because it can be used to target specific genes in

> specific parts of the

> brain, the technique could become a valuable tool in

> brain research, said

> Mortimer Mishkin, an NIH neuroscientist who was not

> part of the study.

> " And it's temporary, which is a huge advantage,

> because you can look both

> before and after, " he said.

>