Earlier this year a 22-year-old college dropout, Jared Lee Loughner, shot Arizona congresswoman Gabrielle Giffords through the head near a Tucson supermarket, causing significant damage to Giffords’s brain. In the same shooting spree, Loughner killed or wounded 18 others, including a federal judge and a nine-year-old girl.

Information from Loughner’s postings on YouTube and elsewhere online suggests that he is severely mentally ill. Individuals with serious mental illnesses have perpetrated other recent shoot-ings, including the massacre in 2007 at ­Virginia Tech in which a college senior, ­Seung-Hui Cho, killed 32 people and wounded 17. These events and the accompanying media coverage have probably fed the public’s perception that most profoundly mentally ill people are violent. Surveys show that 60 to 80 percent of the public believes that those diagnosed with schizophrenia, in particular, are likely to commit violent acts.

Although studies have pointed to a slight increase in the risk of violent behaviors among those afflicted with major psychiatric ailments, a closer examination of the research suggests that these disorders are not strong predictors of aggressive behavior. In reality, severely mentally ill people account for only 3 to 5 percent of violent crimes in the general population. The data indicate that other behaviors are likely to be better harbingers of physical aggression—an insight that may help us prevent outbursts of rage in the future.

A Tenuous Tie
Not all psychological and emotional disorders portend violence, even in society’s eyes. In this column, we refer only to severe mental illness—meaning schizophrenia, bipolar disorder or psychotic depression. Symptoms of schizophrenia include marked disturbances in thoughts, emotions and behaviors; delusions (fixed false beliefs); hallucinations (perceiving things that are not physically present); disorganization; and withdrawal from social activities. Bipolar disorder is usually characterized by swings between depression and mania, which involves euphoria and grandiosity, a boost in energy and less need for sleep. Psychotic depression includes acute depressive symptoms, along with delusions or hallucinations, or both.

Most researchers investigating the question of aggression in the mentally ill have found a small but telling association between violence and significant psychological disturbance. In a 2009 meta-analysis, or quantitative review, of 204 studies exploring this connection, psychologist Kevin S. Douglas of Simon Fraser University and his associates found a slightly greater likelihood of aggressive behaviors among those with severe mental illnesses.

Yet this connection is much weaker than the public seems to believe it is and does not necessarily mean that these serious disorders cause violence. The causation could be in the reverse direction: engaging in chronic aggression (stemming from some other source) may create stress that triggers the illness in those predisposed to it. Alternatively, a third factor could spawn both a psychiatric condition and violence.

Rather than thinking of people with severe mental illness as generally dangerous, scientists are now pinpointing those other factors that might augur violent behavior more reliably. One strong candidate is drug abuse. Revealing results from the MacArthur Violence Risk Assessment Study in 1998, sociologist Henry J. Steadman of Policy Research Associates and his colleagues reported that almost a third of severely mentally ill patients with substance abuse problems engaged in one or more violent acts in the year after they left the hospital. For discharged patients who did not abuse drugs, the corresponding figure was only 18 percent. (That figure suggests that less than one fifth of severely mentally ill individuals without other issues are dangerously aggressive.)

In its meta-analysis, Douglas’s team also flagged drug abuse as one of several factors that contributed to the connection between mental illness and violence. In addition, it found the link was even stronger for patients who suffered from delusions, hallucinations or disorganized thinking. Thus, a mentally ill person is more at risk of committing an act of aggression when that individual is also abusing a drug and shows particular symptoms.

10 Comments

1. 1. Atomboy 05:37 PM 7/8/11

   I work with people who have a serious mental illness. I've been punched once in seven years and have never felt that I was in danger of dying. Aside from those whose disease prevents good communication I enjoy the company of our patients and look forward to seeing them. The only serious beatings I ever received in life came from "normal" people.

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2. 2. pabloson 05:52 PM 7/8/11

   I agree with Atomboy. I work with the mentally ill as well and facilitate a mental illness forum on the internet. My forum is much more civil than any other forum I have ever come across! Mentally ill people are often characterized by a high level of empathy and sensitivity. When you spend your life struggling and suffering, it can help to develop heightened empathy which is probably a deterrent to violence.
   
   One thing I thought was missing from the article is a mention of antisocial personality disorder (formerly sociopathic disorder). This disorder IS characterized by uncivil and violent acts against people and society. Ted Bundy is one famous example and you could probably lump most terrorists in there as well. Sociopaths are characterized by lack of remorse so they don't need drugs to impair their impulse control before committing a violent act.

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3. 3. jtdwyer in reply to pabloson 12:07 AM 7/9/11

   Good point regarding sociopathic behavior, which seems to me to be common among serial killers.
   
   It also seems to me that when severely disturbed people do lash out at others their violent actions often seem to be without rational motive that the public can relate to.
   
   I think this is why the public finds such seemingly pointless violent behavior so shocking, while they can generally comprehend that Ted Bundy was acting out of some desire for twisted self-gratification...

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4. 4. bloomingdedalus 08:04 AM 7/9/11

   pabloson -> I find your characterization of mentally ill as being highly empathetic interesting. An empathetic person is not only prone to depressive behavior for their own suffering, but also engages in it because of others. American society, at large, is not empathetic. You can find a recent article in Scientific American that even states there is a massive decline in empathy among young persons in the United States.
   
   For myself, empathy has been a devastating condition which has tormented me wherever I go. It draws me toward people who cannot help me advance in the world and alienates me from those who are not afraid to whole-heartedly embrace brutal and selfish capitalism. It has alienated me from studying trade skills in favor of religious and humanistic literature.
   
   Empathetic behavior in society, especially in excess, is always a threat to the status quo. Major empathetic types in the world have been persistently assassinated or executed, such as Jesus of Nazarath, MLK, John Lennon, etc..
   
   For this reason, it is hard to dismiss the plausibility given your assertion as well as my own encounters with meek persons who have been categorized as mentally ill that some diagnoses of mental illness are politically motivated.
   
   It is disturbing that people place so much inherent trust in the DSM's assertions regarding what constitutes "ill" behavior when in few cases can it be empirically verified. We must remember that the APA considered homosexuality to be a mental illness until as late as the 70's, completely proving their lack of empirical evidence for that which they assert as being disorders.
   
   In my personal experience with mental health professionals, I have found their desire to use the DSM as a weapon rather than a guide quite distasteful, and have, more than once, had these professionals disregard actual experiences as delusions while I was pursuing litigation against some fairly large organizations who had, multiple times, threatened to murder me.
   
   Essentially, it is hard to regard the American Psychological Association's criteria for mental disorders as evident of anything other than a blind categorical book based on nothing but some sociologist's arbitrary taxonomy of mental paradigms purposed only for the control of the labor population.
   
   Your characterization of the empathetic as those who get dismissed as crazy is not only accurate, it is a CONSTANT because group-think overshadows the individual in all circumstances.
   
   Twain wrote of this tendency in "War Prayer," I believe you would find it enlightening.
   
   

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5. 5. letxequalx 08:53 AM 7/9/11

   I don't know if it "holds water" statistically but wouldn't it makes sense that less of these individuals would act out violently if they had another way to communicate or connect. I notice that Jared Lee Loughner didn't become violent while he was in therapy or attending classes or while he owned a pet. It seems that in many of these cases violence occurs after the individuals illness has put them in social isolation.

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6. 6. bloomingdedalus 09:53 AM 7/9/11

   Illness is not the only cause of social isolation. There are people in the world who have no friends and consistently cannot make them. Poverty, religion, race, gender, and social lines also contribute to social isolation.
   
   If you ask me though, I think there's groups of people who intentionally target socially isolated people and try to torment them to death, like foxhunting used to be a popular sport for rich kids.

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7. 7. mrbadhabits 07:48 PM 7/25/11

   symptoms of serious mental illness such as schizophrenia usually begin by young adulthood, and the victims have great difficulty finding appropriate therapy. few psychiatrists in private practice treat them, focusing instead on patients who have money to pay the bill, usually show up for appointments, and take the inevitably prescribed meds - in short, nice neurotics aka the "worried well". meanwhile the really sick people have to do something overtly "crazy" (not to say violent) in order to be taken to a local psych emergency room and then perhaps on to the local psych hospital. they are "stabilized" for a few weeks on meds, released, only to return again and again. no surprise that those few who do act out violently are not effectively treated earlier - neither are the many others who are non-violent.

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8. 8. Loren Wingblade Ph.D. 05:18 PM 7/26/11

   To bloomingdedalus:
   I hate to say this but you are wrong. Empathy does not lead to depression or mental illness. The latest findings from a new sub-discipline of psychology called "moral psychology" an outgrowth from cognitive psychology finds that both psychopaths and autistics lack empathy. Now, the research is focused on why psychopaths break the law and autistics generally don't. The best guess is that psychopaths want to dominate and autistics don't. Read the book "The Science of Evil: On Empathy and the Origins of Cruelty" by Simon Baron-Cohen, or look up on Google, Jonathan Haidt's papers on moral psychology, or better still go to Amazon.com and look up the three volume set titled "Moral Psychology."
   Depression is not linked to having/not having empathy but to hopelessness. Hoplessness is the best predictor of depression.
   Loren Wingblade

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9. 9. Squeedle in reply to pabloson 05:02 AM 10/6/11

   Psychologists have interviewed terrorists and concluded that they are not mentally ill, in general, so no, you can't "probably lump in most terrorists" in that category. ( Sources: http://news.bbc.co.uk/2/hi/3880777.stm and http://www.project-syndicate.org/commentary/dphoughton1/English )
   

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10. 10. davinjoel in reply to Loren Wingblade Ph.D. 05:20 AM 4/23/13

    Unfortunately, Dr. Wingblade, your assertion about empathy in regard to psychopaths and autistics is false - the distinction must be made between cognitive and affective empathy. The former is known as 'theory of mind' and autistics lack this greatly. However, psychopaths have a great ability with theory of mind - in other words, they are able to predict states of mind of other people. What they significantly lack, however, is affective empathy. An emotional caring for the wellbeing of others. They simply disregard this. Autistics, on the other hand, have normal-to-above-average affective empathy levels, but below-average cognitive empathy. They have greater difficulty inferring states of mind than most others, but this does not imply they do not care about others. I agree with your comments on depression though - a loss of hope is often what precipitates such a drop in mood that can trigger a depressive episode.

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