Depression focus of NZ study
AUCKLAND: A New Zealand study will attempt to reveal what happens to our brains when we take antidepressants and whether these changes can be easily measured.
Despite the widespread prevalence of depression (one in seven Kiwis experience it before the age of 24), accepted treatments fail to work for about onethird of patients.
A lack of understanding of the biological causes of depression has hampered drug development but there is hope advances in brain imaging technology could offer new ways to measure the socalled ‘‘biomarkers’’ of central nervous system disorders.
These natural indicators in the brain could help scientists not only get to grips with what causes disorders such as depression, but how these disorders might be predicted and how treatments can be effectively evaluated.
A project by a University of Auckland researcher will draw on widely used brain imaging technology, MRI and electroencephalography (EEG), to measure biomarkers of signs of excitation and inhibition in the cortex.
The study would also hunt for changes in the brain’s ‘‘neural plasticity’’, something Rachael Sumner, of the university’s School of Psychology, expected to see increase after antidepressants were taken.
‘‘Neural plasticity is a term we use to describe learning and memory but it means learning and memory at every level of the brain,’’ she said.
It meant the brain itself did not grow larger but that neural pathways became better connected.
‘‘So it’s not simply learning one plus one equals two, but that the brain learns to function more effectively in everything that it does.’’
Reduced neural plasticity has been implicated in various brainbased disorders, including depression.
‘‘Whether it mediates the antidepressant response, however . . . that’s something we are still working out.’’
Patients in the study would look at patterns and listen to tones that trigger visual or auditory activity.
‘‘We’ll be using an antidepressant that we know works very quickly and should allow us to study the effects in a way that hasn’t been done before.’’
Ultimately, she hoped identified changes in sensory neural plasticity could be used as biomarkers of general brain health in depression.
The study would also be one of the first in the world to search for these changes with the simultaneous use of MRI and EEG.
‘‘A big part of it will be whether we can actually measure it with EEG, which is already in hospitals and clinically available.’’
Being able to use this technology, much more affordable than MRI or magnetoencephalography, could improve development of new drugs.
The study will take two years.