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“The hopes and claims for brain imaging in psychiatry have far outpaced the science,” writes Benedict Carey in the New York Times. “In this field,” one expert told him, “every year you hear, ‘Oh, it’s more complicated than we thought.’ Well, you hear that for 10 years, and you start to see a pattern.” This has led to “a growing sense that brain scan research is still years away from providing psychiatry with anything like the kind of clear tests for mental illness that were hoped for,” says Carey.

Wide variation in the brains of different individuals and at different ages within the individual further complicates an already complex organ. For example, while a ten percent reduction in brain volume can suggest schizophrenia, brain volume itself varies by at least ten percent from person to person. Or “what looks like a ‘hot spot’ of activity change in one person’s brain may be a normal change in someone else’s.”

Then there are differences of scientific opinion about the conclusions of brain imaging research. And “Most fundamentally, imaging research has not answered the underlying question that the technology itself has raised: which comes first, the disease or the apparent difference in brain structure or function that is being observed?” It would take a massive and prohibitively expensive longitudinal study to answer that question.

Still, there are tantalizing instances where scanning appears, at first glance, to have paid off. One is PET scan-based research at Emory University that led to the discovery that Brodmann area 25 in the brain is involved in depression, which in turn led to a study at the Rotman Research Institute in Toronto of six depressed patients who had electrodes implanted in their brains next to Brodmann area 25. Four of the six patients had significant and lasting recovery as of October. However, this study’s results may not be generalizable to the larger population of depressed people.

Even with its drawbacks, one doctor consider it “unconscionable” that psychiatrists do not make more use of brain scans. He claims the many SPECT scans he performs help him to distinguish between children with attention deficit problems who respond well or poorly to specific stimulants. He also argues that imaging provides patients with evidence of a biological basis to behavior problems they might otherwise deny.

Imaging technology and our understanding of the brain are both advancing, and the story is not over yet.

Menstrual Software

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Research showing contrasts in brain activity over the course of a month may help explain the emotional and behavioral changes that 75 percent of pre-menopausal women experience before, during, and after menstruation, reports Scientific American.

Cornell University’s Weill Medical College neuroscientists used functional magnetic resonance imaging (fMRI) to monitor the activity of the orbital frontal cortex, which is known to be associated with regulating emotion and controlling behavior, in 12 healthy women between the ages of 22 and 35 while they read a series of negative, neutral, and positive words intended to provoke emotional responses.

At different phases of the menstrual cycle, the subjects showed greater activity in different parts of the brain. The researchers speculate that the reallocation of activity from one part of the brain region to another may reflect the organ’s ability to compensate for hormonal changes and help a woman maintain a consistent emotional state.

Nanoimaging

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Materials scientists at Northwestern University have developed a method called “scanning near-field ultrasound holography” able to see up to one micron deep inside materials and cells, where the researcher can then spot nanoscale defects in microelectronic structures or watch malaria parasites inside living red blood cells in real time.

Its developers say it is “a pretty cheap technology that can fit on any scanning probe microscopy platform.” The current version uses piezoelectric crystals oscillating at roughly 30 or 40 megahertz, which enable it to resolve objects as small as 20 nanometers. The next version will have gigahertz oscillators enabling it to resolve 1-nanometer-sized details up to 3 microns below the surface. A future version may be able to produce three-dimensional images.