Electronic mapping of brain signals can assist in diagnosing mental conditions.
Credit: Photolibrary
LAUREN BACK ALWAYS KNEW something was wrong with her mind, she just didn’t know what it was. “I always tried so hard at school but just wasn’t able to do it,” she says. “When I struggle, my mind is always where I don’t want it to be. I can’t help it if I don’t like the light, or if I’m not the right temperature. I can’t help it if I just had an argument on the phone before studying … But I knew that couldn’t be normal.”
With a family melting pot of disorders – her father has bipolar disorder and attention deficit hyperactivity disorder (ADHD), and her mother suffers from chronic fatigue syndrome, alcoholism and depression – Back inherited a susceptibility to psychiatric conditions.
At 16, the American teenager was diagnosed and treated for depression and anxiety, but her slow reading skills, poor time management, lack of concentration and procrastination continued. When the stresses of Back’s first year at the University of Colorado at Boulder tipped the journalism student into a breakdown, she knew there was more to her problems. “I just wasn’t surviving,” she says.
Determined to find out what was going on in her head, Back, now 23, sought help at a clinic in Boulder, Colorado. “I brought in a list of things that I knew just weren’t right,” she says. “It was a page long.”
The clinic used a powerful new technique which helps diagnose and treat mental disorders by peering into patients’ brains and analysing waves of electrical activity. Called quantitative EEG (short for electroencephalogram), or QEEG, the process detects biological markers for psychiatric disorders by measuring distinct patterns in a person’s brain waves.
Back’s QEEG results boiled down to charts, numbers and a two-dimensional map of her brain highlighting areas of weakness. Her brain waves revealed classic markers of ADHD.
Brain waves are electrical signals generated when neurons fire, and like instruments in an orchestra, different neurons have different frequencies at which they discharge.
Advances in computing in recent decades have allowed scientists to apply increasingly powerful mathematics to help glean more from an EEG than they can see unaided. These computations – the QEEG – show patterns such as the strength of brain waves at a particular frequency, the relationship between the waves, or how much the waves are in sync. The data are represented by scores and charts and mapped onto two-dimensional pictures of the brain. And slowly, researchers have found specific brainwave patterns that correlate to dozens of conditions, from ADHD and schizophrenia, to depression and dementia.
“The profile of a schizophrenic patient looks very different from a depressed patient. They each indicate abnormalities, but there are distinctive patterns,” says neuropsychiatrist Leslie Prichep, associate director of the Brain Research Laboratories at New York University, based at New York’s famed Bellevue Hospital. She has spent more than 30 years researching QEEG.
The use of such technology in psychiatry signifies the current shift in the field from a symptoms-based approach to diagnosing and treating mental disorders, to a more evidence-based approach that looks at the underlying causes of malfunctions in the mind.
As part of this shift, psychiatrists are beginning to readdress how disorders are classified and what ‘normal’ really means.
“It’s a wonderfully exciting time,” says Kerry Coburn, professor of psychiatry and behavioural sciences at Mercer University School of Medicine in Macon, Georgia. “ We’re moving from general psychiatry to an era of neuropsychiatry where psychiatric disorders, or at least the major ones, are considered to be disorders of the brain.”
