Image: TinEye
-
The Wisdom of Psychopaths
In this engrossing journey into the lives of psychopaths and their infamously crafty behaviors, the renowned psychologist Kevin Dutton reveals that there is a...
Read More »
Once adult lab mice learn to associate a particular stimulus—a sound, a flash of light—with the pain of an electric shock, they don't easily forget it, even when researchers stop the shocks. But a new study in the December 23 issue of Science shows that the antidepressant Prozac (fluoxetine) gives mice the youthful brain plasticity they need to learn that a once-threatening stimulus is now benign. The research may help explain why a combination of therapy and antidepressants is more effective at treating depression, anxiety and post-traumatic stress disorder (PTSD) than either drugs or therapy alone. Antidepressants may prime the adult brain to rewire faulty circuits during therapy.
Nina Karpova, Eero Castrén and their colleagues at the University of Helsinki's Neuroscience Center created and extinguished fearful behaviors in mice. First, Castrén placed mice in a cage and repeatedly played a tone just before electrically shocking their feet. Soon the animals froze in fear whenever they heard the tone, at which point Castrén put them through "extinction training." He moved the mice to a different cage and played the same tone again. This time there was no electric shock.
Researchers have previously shown that young mice less than three weeks old quickly learn that the tone is no longer a herald of danger and stop freezing in fear. But adult mice are harder to put at ease. Even if the adults become less fearful during extinction training, their relaxation is not permanent—a week later the tone turns them into statues again.
In Castrén's study, adult mice that took fluoxetine while they went through extinction training behaved much like young mice—they lost their fear much faster than mice that were not taking the drug, and their anxiety did not return. In contrast, mice that were given fluoxetine but never went through extinction training remained anxious.
Castrén makes an analogy between these findings and the consensus that antidepressants in combination with therapy are almost always more effective than either antidepressants or therapy alone. Scientists know what most antidepressants do at the molecular level—they change the amounts of neurotransmitters in the spaces between neurons, for instance—but how these changes treat depression remains an open question. Research has not supported the idea that antidepressants treat depression simply by correcting chemical imbalances in the brain. More recently, researchers have hypothesized that depression kills neurons whereas antidepressants like Prozac encourage new neural growth in the brain. Castrén's study suggests Prozac returns regions of the brain to an immature state in which neurons make or break more connections with one another than is typical of the adult brain. In other words, Prozac increases brain plasticity.
Castrén looked for characteristic electrical and molecular signs of plasticity in the brains of mice that received fluoxetine and in those that did not. Specifically, Castrén looked in the amygdala at neural circuits responsible for fear responses. He found that fluoxetine increased levels of a cell-adhesion molecule associated with young neurons and decreased the levels of a transporter protein associated with adult neurons. He also found greater changes in membrane potential in neurons from the brains of mice that had learned to relax. These neurons were also better at synchronizing their communication through a process called long-term potentiation, which is crucial for learning and memory.
"We know that a combination of antidepressant treatment and cognitive behavioral therapy has better effects than either of these treatments alone, but the neurobiological basis is not known," Castrén says. "We show a possible mechanism is bringing the network into a more immature and plastic state."
See what we're tweeting about
24 Comments
Add CommentResearch of 2011 shows rats exposed fetally to SSRI (antidepressants) demonstrate autistic behavior. So this way to overcome learned helplessness is totally unacceptable. Consider that an enormous population of child bearing age women routinely take SSRIs and the mystery of the unusually large population of autistic children to educated women is solved.
Reply | Report Abuse | Link to thisThis wd also explain why I find that some of my mature friends who have been on SSRIs for a while seem to have developed a cheery but child-like attitude whilst still in their late 40s, early 50s. As parents they often seem to be eerily abstracted and happy-go-lucky, with great difficulty in spotting problems they might help avert let alone setting any sort of limits to their teenage children, trying to behave more like ´chums´. Interesting, but as katesisco reports, unacceptable?
Reply | Report Abuse | Link to thisPeople that are mentally ill pass these genes along to their kids.
Reply | Report Abuse | Link to thisAntidepressants are not needed.
Autistim has been proven, many times over, that it is NOT caused by outside factors.
Why do you have a problem with the truth?
A Winnepeg MB judge says it is ok to kill someone if you are on prozac.
Reply | Report Abuse | Link to thisto be blunt, im sure you could roll all your problems out the joint by just breathing right. inhaling...exhaling...inhaling...exhaling
Reply | Report Abuse | Link to thisvisit your local greenery and loosen up those synapses.
Well, that seems an accurate observation of today's people's behaviours. However, are you sure that it correlates with SSRIs? There are many other factors which could easily explain that trend. To name just a few:
Reply | Report Abuse | Link to this- until 2 generations ago most people grew up with several siblings, today many grow up as only kids; this could have two effects:
1st: only kids do not learn to set limits early on as well, since they do not have to fight constant competition from their siblings
2nd: since today's parents are generally older than in former times and have less children, they treat their kids more like treasures and tend to pamper them too much
- advertisers are increasingly tricking people into an adolescent kind of consuming behaviour
- it's en vogue to "stay young" both in looks and behaviour (see the stats about cosmetic surgery for a start)
I truly think that sdmace's observations are not due to SSRIs...
Does either CBT or Prozaic give the rat better behavior when the rat is shocked? It seems to me that stopping the shocks would be the key prerequisite to the desired behavior. Can the rat continue to get shocked and become resilient with the combined treatment?
Reply | Report Abuse | Link to thisIn many cases humans unavoidably continue to receive stressors while they are in therapy and on medication. Do they become more resilient and adaptable in the face of the continuing stressors?
"People that are mentally ill pass these genes along to their kids"
Reply | Report Abuse | Link to thisI wonder what illness you are referring to? Because it's mostly something like "mental illnesses" have a genetic component that varies from 0 to 50%.
"Antidepressants are not needed"
What do you mean? Placebos are just about as good? Or
"Autistim has been proven, many times over, that it is NOT caused by outside factors"
Certain factors have been shown to not be specific causes of autism but that does not mean outside factors or combinations of outside factors are not causes of autism (and the dichotomy between inside and outside factors is not as clear as it may appear).
"Why do you have a problem with the truth?"
Latest research on autism found that mothers who took a multi-vitamin reduced incidence of autism by 42%. This is similar to reduction in neural tube defects of up to 80% if mother takes enough folic acid/folate. Poor nutrition of mother, even father-sperm-DNA donor, show up in children and later generations. Any drug in a mother is a bad idea. Any improvement in nutrition is a good idea, especially the basics of protein, multi-vitamin, minerals, vitamin D3, and Omega 3's (brain developement.) Lots of USA's poor health statistics relate directly to bad food choices and the rise of fast food.
Reply | Report Abuse | Link to thisA disorder can be genetic without coming from the parents. If there is a de novo mutation in the germ line of the affected individual, then the parents will not be the source of the genetic mutation. This is thought to occur in a fairly large percentage of cases of developmental brain disorders such as schizophrenia and autism.
Reply | Report Abuse | Link to thisThese genes tend not to persist because these disorders tend to greatly reduce reproductive fitness. Moreover, there are many genes which affect brain developmebnt in humans, so there are many possible mutations which can cause developmental brain disorders. This may explain why schizophrenia has been linked to many different mutations, none of which account for more than a small percentage of cases.
Good points which I recognize, yes, but the ones on SSRIs are quite different from the ones not taking anti-depressants; their behaviour is more child-like, happy-go-lucky and interestingly, now that you mention it, less focussed on their looks, more casual about ageing.
Reply | Report Abuse | Link to thisMy ex loved getting prozac from immigrant doctors. The side effects occurred on those around her. One was born mentally challenge,my neighbour drove into a truck. Isn't that sweet.
Reply | Report Abuse | Link to thisI think you have bad information. Some genetecists claim autism is 90% genetic, but there is lots of evidence for a very big environmental factor. And of the environmental part, the prenatal environment is very important. I don't know if there is any reason to suspect SSRIs particularly but drugs and pregnant women are a dangerous combination for the children.
Reply | Report Abuse | Link to thisSome autism points:
Reply | Report Abuse | Link to this1. Scientists at UC Davis have discovered a pattern of maternal antibody to fetal brain in about 12% of mothers of autistic children, NEVER found in mothers of non-autistic children. Additionally, a related antibody pattern accounts for about another 5%. So, that's between 15% and 20% of all cases.
2. A recent twin study from Stanford found concordance rate for fraternal twins MUCH higher than for siblings. This means a very large environmental component to autism. Environmental does not mean mercury, lead, vaccines, etc, it means the maternal antibodies and other in utero effects, but that could include drugs taken by mother in pregnancy.
i totally agree. While reading i was finding the article interesting however i was wondering about the adverse effects of such "dumbing down" of one's adult brain. It seems that an adult effectively looses their ability to "reason" or this thing we consider "wisdom".
Reply | Report Abuse | Link to thisWhat do you define as "mentally ill"? Can you provide an example (for discussion sake)?
Reply | Report Abuse | Link to thisYes, I agree that these are important causes as well - however, the people I refer too and are on SSRI are different, insofar as they are a bit zoned out, and do take the no limits to extremes, not as a stance, but as a ´could not be bothered´ attitude, and all is always fine and 'ok by me'as long as i am not troubled by things.
Reply | Report Abuse | Link to this"Learned helplessness"
Reply | Report Abuse | Link to thisHmm.
I suffer from depression and let me tell you, it's a lot more complicated than that. It's debilitating. You have periods of overwhelming sorrow for no reason and you know it's for no reason, so you get SO angry for yourself for how "stupid" you're being and it's a self perpetuating self-hate spiral. It's almost impossible to concentrate on anything because you just can't bring yourself to care. You go through the motions of work and class and fail midterms and finals because as much as half of your brain tells you that you NEED to do this, you still can't bring yourself to care.
If you go through that for years and you find a drug that HELPS you, I find that acceptable.
As someone who has taken Prozac, I am rather skeptical of these claims. I can verify the observation of the commenter who spoke of the eerie 'cheery but child-like attitude whilst still in their late 40s, early 50s. As parents they often seem to be eerily abstracted and happy-go-lucky...'
Reply | Report Abuse | Link to thisIt was like that from the inside too, plus some nasty side effects: anxiety (yes!), craving for sugar, alcohol... I do not normally like either. Dopamine is crucial to learning and memory (and feeling well), so downregulating it seems an unlikely way to increase those functions. Rather one seeks out other means of getting the dopamine back. Shopping, gambling, etc.
My brain felt *made* of plastic, but that's about as far as that went.
Interesting the talk about autism: a recent study shows that SSRIs in particular cause significant increase in incidence of ASD: http://www.medpagetoday.com/Pediatrics/Autism/27403?utm_content&utm_medium=email&utm_campaign=DailyHeadlines&utm_source=WC&userid=356450
And that environmental causes apparently do trump genetic ones: http://www.medpagetoday.com/Pediatrics/Autism/27407?utm_content&utm_medium=email&utm_campaign=DailyHeadlines&utm_source=WC&userid=356450
It's also a perfect storm of (epi)genetic factors and poisoning from neurotoxic metals and the other chemicals with which we've saturated our environment... based on the mounting evidence I believe that this accounts for the sharp increase in severely affected children. A new and thorough study on aluminum used as a vaccine adjuvant and ASDs is looking like a smoking gun, and there was a sharp spike in autism right after we began using fetal cell lines to create vaccines. I'm sure the intention was only the best, but the potential for increased autoimmune problems seems rather obvious in hindsight.
Prozac has its place. If you're too depressed to get off the floor, it's certainly worth trying. But for most people, SSRIs simply do not live up to their early (and corrupted) studies. Meta-analyses have shown that for most people, an active placebo would be just as effective, and without the risks of suicide and homicide.
katesisko is correct about the possible adverse effect of SSRIs pre- or perinatally, or in children. The same authors had a paper about early postnatal fluoxetine that led to a depression-like effect in adult mice.
Reply | Report Abuse | Link to thisThe current paper in Science is pointing out the necessity of the exposure therapy (psychotherapy) in addition to the SSRI in order to get the beneficial effect, and explains some molecular mechanisms of SSRI effect.
Thus, one of the important message of that study is not just to take Prozac, but to do it on purpose and under psychologist's surveillance and his/her treatnment.
"Prozac (fluoxetine) gives mice the youthful brain plasticity they need to learn that a once-threatening stimulus is now benign."
Reply | Report Abuse | Link to this'learn' or 'forget'. Huge difference.
It's really scary that we don't know how Prozac actually works and what its effects are. Can we please stop prescribing things that we don't understand entirely?
Reply | Report Abuse | Link to thisSince Fluoxetine increases plasticity as stated threw the empirical evidence in this text, it should be equally stated that if one of the hypothetical conclusion is that because of greater plasticity, patient in therapie rewire to have better faculty that, people using fluoxetine with no therapie or even worse, left in a dysfunctional environment would probably rewire but with the dysfunctional learned behavior.
Reply | Report Abuse | Link to thisTherefore, Fluoxetine should only be given in conjunction with therapie and a removal of the patient with dysfunctional environments and dysfunctional people.
What is this facination about drugs? They are not intelligent, they can never cure the reasons for you anxiety, nor the effects of bulling 20 years ago or the fear you felt everytime your parents were drunk during your childhood. The last 50 years has proven that pills do not cure bad emotions. But here is news for some of you, energy psychology does! I treat and cure anxiety according to my patients, several times a week. And I have done so for many years. SA should write about those results which is easy observable and documented by the only trustable person, the one with anxiety. I live in Europe and are astonished over the trust people in US have in their pills. This is outdated knowledge, and the people who suffers deserves better. We can cure irrational feelings, quick and often. Why is it not interesting for SA to look into that truth? Do I smell money?
Reply | Report Abuse | Link to this