Posts Tagged ‘Columbia University’


A new study finds an algorithmic word analysis is flawless at determining whether a person will have a psychotic episode.

by ADRIENNE LAFRANCE

Although the language of thinking is deliberate—let me think, I have to do some thinking—the actual experience of having thoughts is often passive. Ideas pop up like dandelions; thoughts occur suddenly and escape without warning. People swim in and out of pools of thought in a way that can feel, paradoxically, mindless.

Most of the time, people don’t actively track the way one thought flows into the next. But in psychiatry, much attention is paid to such intricacies of thinking. For instance, disorganized thought, evidenced by disjointed patterns in speech, is considered a hallmark characteristic of schizophrenia. Several studies of at-risk youths have found that doctors are able to guess with impressive accuracy—the best predictive models hover around 79 percent—whether a person will develop psychosis based on tracking that person’s speech patterns in interviews.

A computer, it seems, can do better.

That’s according to a researchers at Columbia University, the New York State Psychiatric Institute, and the IBM T. J. Watson Research Center. They used an automated speech-analysis program to correctly differentiate—with 100-percent accuracy—between at-risk young people who developed psychosis over a two-and-a-half year period and those who did not. The computer model also outperformed other advanced screening technologies, like biomarkers from neuroimaging and EEG recordings of brain activity.

“In our study, we found that minimal semantic coherence—the flow of meaning from one sentence to the next—was characteristic of those young people at risk who later developed psychosis,” said Guillermo Cecchi, a biometaphorical-computing researcher for IBM Research, in an email. “It was not the average. What this means is that over 45 minutes of interviewing, these young people had at least one occasion of a jarring disruption in meaning from one sentence to the next. As an interviewer, if my mind wandered briefly, I might miss it. But a computer would pick it up.”

Researchers used an algorithm to root out such “jarring disruptions” in otherwise ordinary speech. Their semantic analysis measured coherence and two syntactic markers of speech complexity—including the length of a sentence and how many clauses it entailed. “When people speak, they can speak in short, simple sentences. Or they can speak in longer, more complex sentences, that have clauses added that further elaborate and describe the main idea,” Cecchi said. “The measures of complexity and coherence are separate and are not correlated with one another. However, simple syntax and semantic incoherence do tend to aggregate together in schizophrenia.”

Here’s an example of a sentence, provided by Cecchi and revised for patient confidentiality, from one of the study’s participants who later developed psychosis:

I was always into video games. I mean, I don’t feel the urge to do that with this, but it would be fun. You know, so the one block thing is okay. I kind of lied though and I’m nervous about going back.

While the researchers conclude that language processing appears to reveal “subtle, clinically relevant mental-state changes in emergent psychosis,” their work poses several outstanding questions. For one thing, their sample size of 34 patients was tiny. Researchers are planning to attempt to replicate their findings using transcripts from a larger cohort of at-risk youths.

They’re also working to contextualize what their findings might mean more broadly. “We know that thought disorder is an early core feature of schizophrenia evident before psychosis onset,” said Cheryl Corcoran, an assistant professor of clinical psychiatry at Columbia University. “The main question then is: What are the brain mechanisms underlying this abnormality in language? And how might we intervene to address it and possibly improve prognosis? Could we improve the concurrent language problems and function of children and teenagers at risk, and either prevent psychosis or at least modify its course?”

Intervention has long been the goal. And so far it has been an elusive one. Clinicians are already quite good at identifying people who are at increased risk of developing schizophrenia, but taking that one step farther and determining which of those people will actually end up having the illness remains a huge challenge.

“Better characterizing a behavioral component of schizophrenia may lead to a clearer understanding of the alterations to neural circuitry underlying the development of these symptoms,” said Gillinder Bedi, an assistant professor of clinical psychology at Columbia University. “If speech analyses could identify those people most likely to develop schizophrenia, this could allow for more targeted preventive treatment before the onset of psychosis, potentially delaying onset or reducing the severity of the symptoms which do develop.”

All this raises another question about the nature of human language. If the way a person speaks can be a window into how that person is thinking, and further, a means of assessing how they’re doing, which mechanisms of language are really most meaningful? It isn’t what you say, the aphorism goes, it’s how you say it. Actually, though, it’s both.

As Cecchi points out, the computer analysis at the center of the study didn’t include any acoustic features like intonation, cadence, volume—all characteristics which could be meaningful in interpreting a person’s pattern of speaking and, by extension, thinking. “There is a deeper limitation, related to our current understanding of language and how to measure the full extent of what is being expressed and communicated when people speak to each other, or write,” Cecchi said. “The discriminative features that we identified are still a very simplified description of language. Finally, while language provides a unique window into the mind, it is still just one aspect of human behavior and cannot fully substitute for a close observation and interaction with the patient.”

http://www.theatlantic.com/technology/archive/2015/08/speech-analysis-schizophrenia-algorithm/402265/

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We have all experienced the aftermath of a bad night’s sleep: grogginess, irritability, difficulty carrying out even the simplest of tasks. A growing amount of research suggests that not getting enough shut-eye could also have insidious effects on heart disease, obesity and other conditions.

The American Academy of Sleep Medicine, the largest physician-based organization for sleep medicine, recently put out their first recommendations for what is the right amount of sleep. It advises that adults get at least seven hours every night based on research on the link between inadequate sleep and a number of poor health outcomes.

Although most of us already know that we should get at least seven hours of sleep, a study last month suggested that Americans are creeping down to that cutoff. The average amount of sleep that they reported getting a night has dropped from 7.4 hours in 1985 to 7.29 hours in 1990 to 7.18 in 2004 and 2012.

The Centers for Disease Control and Prevention, which requested and helped support the development of the current recommendations, has called not getting enough sleep a public health epidemic.

For many aspects of health, “it was quite clear that seven to nine hours was good,” said Dr. Nathaniel F. Watson, president of the American Academy of Sleep Medicine and a professor of neurology at University of Washington. Watson led the panel of experts that wrote the recommendations. The group looked at more than 300 studies.

Getting only six hours of sleep a night or less was associated with setbacks in performance, including mental alertness and driving ability, and increased risk of heart attack, stroke, diabetes and obesity, Watson said.

There were not enough studies looking at the health of people who got between six and seven hours of sleep or more than nine hours to know how their health fared.

The panel did not put an upper cutoff on the amount of sleep a person should get because, in addition to the lack of evidence, “there are instances where a person might sleep longer if they are recovering from a sleep debt or illness, and we had trouble coming up with a biological way that sleep would be bad for you,” Watson said.

Although there have been reports that sleeping nine hours or more a night is associated with increased risk of death, that link probably has more to do with the fact that the people who slept a lot had underlying illnesses that ultimately did them in, said James Gangwisch, a sleep researcher at Columbia University who helped develop the current recommendations.

In addition, reports of sleeping a lot may actually be an indicator that a person is not exercising or socializing, which can carry health risks.

Sleep and how it relates to body mass and more

The panel looked at studies that reported connections between the amount of sleep that people said they got and their health over long periods. The panel also took into consideration studies that monitored people in sleep labs that controlled how much sleep they got.

For example, Gangwisch and his colleagues have reported a connection between getting less than seven hours of sleep a night and high body mass index. Separate studies in sleep labs suggest how inadequate sleep could lead to obesity: it drives up the levels of appetite-inducing hormones.

The weight gain that might be caused by inadequate shut-eye could, in turn, increase the risk of heart attack and stroke, Gangwisch said. In addition, sleep deficits seem to increase blood pressure as several studies have found, which could be bad for heart health.

One small study found that healthy adults had higher blood pressure after a night when they were only allowed to sleep four hours compared with a night when they were allowed to sleep for eight hours.

It is hard to say, however, if depriving people of sleep for an extended period would have lasting effects on blood pressure and appetite, even though studies linking sleep deprivation with heart disease and weight gain suggest so.

Sleep lab studies usually only investigate the effect of abridged snoozing for several nights, but people might adjust somewhat to sleep deprivation if it became the norm for them, Gangwisch said.

Although the recent recommendations are for the appropriate amount of shut-eye, getting bad sleep could be just as harmful as not getting enough sleep. Among the most common sleep disorders are insomnia and obstructive sleep apnea, which causes people to stop breathing intermittently throughout the night. About 10% of adults have chronic insomnia; obstructive sleep apnea affects an estimated 24% of men and 9% of women.

Obstructive sleep apnea in particular can take a toll in many ways beyond just shortening the amount of sleep you get, Watson said. The condition can increase blood pressure (separately from the effect of not getting enough sleep), deprive the body of oxygen, cause irregular heartbeat and make the blood more sticky, all of which can increase the risk of heart disease and stroke, he said.

A study that was presented this week at the European Society of Cardiology meeting found that men who had a sleep disorder were between 2 and 2.6 times more likely to have a heart attack and 1.5 to 4 times more likely to have a stroke over the 14-year period of the study.

Not sleeping well? Talk to the doc

“This study underscores to me the importance that if a person doesn’t think they are sleeping well, they should talk to their doctor,” said Kristen Knutson, an assistant professor of medicine at the University of Chicago who was not involved in the study.

Signs that you are not sleeping well or enough include needing a lot of caffeine to get through the day and falling asleep during a meeting or movie, which Knutson said does not usually happen in well-rested people no matter how bored they are.

ome people might need more or less than seven hours of shut-eye. To know what is right for you, see how long you sleep when you are a couple of days into a vacation and the alarm does not go off, Knutson suggested. (The first couple of days you might sleep longer because you are catching up.)

Knutson agrees with the advice that there does not seem to be a danger in sleeping too much. “People generally don’t sleep more than they should, and if you are laying in bed and can’t sleep, the general recommendation is to get up,” she said.

There are a number of strategies for making the most of your slumber. These include going to sleep and waking up about the same time every day, making your bedroom dark and cool and avoiding caffeine too close to bedtime.

“Some people view sleep as an obstruction to success, and we would rather have people view it as a tool for success,” Watson said. “We really want people to prioritize their sleep and understand that it is as important to their overall well being as diet and exercise,” he added.

http://www.cnn.com/2015/06/19/health/sleep-or-die/index.html

“I grew up in the hood in Miami in a poor neighborhood. I came from a community in which drug use was prevalent. I kept a gun in my car. I engaged in petty crime. I used and sold drugs. But I stand before you today also — emphasis on also — a professor at Columbia University who studies drug addiction.”

That’s how Dr. Carl Hart, a neuroscientist and professor of psychology and psychiatry, opened a recent TED talk he gave about his research into addiction. After his difficult youth, Hart said he toed the drug war line for a number of years: “I fully believed that the crime and poverty in my community was a direct result of crack cocaine.” He bought into the notion, pushed by policymakers in the 1980s and 1990s, that you could get hooked on crack and other drugs after just one hit.

But his research has disabused him of these notions. He recruited cocaine and meth users into his lab, and over a period of several days offered them some options: they could either receive hits of their drug of choice, or they could take payments of five dollars instead. Crucially, the payments offered were less than the value of the drugs they could consume.

Contrary to the notion of the craven drug fiend who will do literally anything for one more hit, Hart found that half of cocaine and meth users opted for the money over the drugs. And when he increased the payments to 20 dollars, closer to 80 percent of meth users chose the money. The lesson? “Attractive alternatives dramatically decrease drug use,” he said in his talk.

This speaks to another point Hart made, which is worth quoting at length:

80 to 90 percent of people who use illegal drugs are not addicts. They don’t have a drug problem. Most are responsible members of our society. They are employed. They pay their taxes. They take care of their families. And in some cases they even become president of the United States.

He’s right, of course. Among people who have ever used marijuana, only 9 percent become addicted. That rate is 11 percent for cocaine and 17 percent for stimulants like meth. Even the vast majority of people who use heroin — 77 percent of them — never get addicted to the drug.

When it comes to his own kids, Hart, who is black, is less worried about drugs and more worried about the people who enforce drug laws. He says that the effects of drugs at the individual-level are predictable and easy to understand: you smoke some weed, you will experience X effects after Y amount of time. But interactions with the police are a different story. “I don’t know how to keep my children safe with the police because, particularly when it comes to Black folks, interactions with police are not predictable,” he said in a recent Q&A hosted by the Drug Policy Alliance and reported in Ebony magazine.

Thanks to Kebmodee for bringing this to the It’s Interesting community.