Researchers at the University of British Columbia (UBC) have conducted a study that shows chemotherapy can lead to mind-wandering and an inability to concentrate. Long suspected to cause cognitive impairment, the cancer treatment causes what has been dubbed "chemo brain," according to the new study's results.

According to a press release from UBC, breast cancer survivors were asked to complete a set of tasks while researchers monitored their brain activity. What they found is that the minds of people with chemo brain lack the ability for sustained focused thought.

"A healthy brain spends some time wandering and some time engaged," said Todd Handy, a professor of psychology at UBC, according to the press release. "We found that chemo brain is a chronically wandering brain, they're essentially stuck in a shut out mode."

Handy explains that healthy brains function in a cyclic way. People can focus on a task and be completely engaged for a few seconds and then will let their mind wander a bit, but the research team found that chemo brains tend to stay in that disengaged state. To make matters worse, even when women thought they were focusing on a task, the measurements indicated that a large part of their brain was turned off and their mind was wandering.

The researchers also found evidence that these women were more focused on their inner world. When the women were not performing a task and simply asked to relax, their brain was more active compared to healthy women.

"Physicians now recognize that the effects of cancer treatment persist long after it's over and these effects can really impact a person's life," said Kristin Campbell, an associate professor in the Department of Physical Therapy, according to the press release.

Tests developed for other cognitive disorders like brain injury or Alzheimer's have proven ineffective for measuring chemo brain. Cancer survivors tend to be able to complete these tests but then struggle to cope at work or in social situations because they find they are forgetful.

"These findings could offer a new way to test for chemo brain in patients and to monitor if they are getting better over time," said Campbell, according to the press release.

The study appears in the journal Clinical Neurophysiology and received funding from the Canadian Breast Cancer Foundation BC/Yukon.