The human brain is a pretty spectacular organ that continues to surprise researchers as more and more is revealed about it. At the same time, it isn't perfect. Researchers have just found out more about the limitations of the human brain, potentially pinpointing why we tend to ignore other things when focused on one particular task.
In the last few years, researchers from University College London (UCL) have developed a new way to scan brains. As reported by New Scientist, the method was recently used to show that when the brain is engaged in a complicated task, its cells are essentially working at full capacity, so we begin to ignore things going on around us.
The new scanning technique is called functional near-infrared spectroscopy (fNIRS) and measures the activity of a certain enzyme in the mitochondria of neurons. Mitochondria are the powerhouses of cells, so by measuring the enzyme, the team can track the level of activity. This method is similar to functional MRI scans, although despite being cheaper and easier to use, it isn't quite as precise.
Using fNIRS, researchers looked at changes in brain activity during an attention test. Participants were asked to perform a visual task that was either hard or easy. It involved looking out for certain colors or shapes and half of the time a checkered pattern would appear at the side of the screen.
In the easy task, the checkered pattern had an effect. Brain cells associated with peripheral vision became a lot more active. However, in the hard task, a much less significant effect was seen. The findings, presented at the UCL Neuroscience Symposium earlier this summer, suggest that activity in regions not focused on the matter at hand becomes suppressed.
This is not the first study to suggest why focusing on multiple things is extremely difficult for most people and why multitasking can have a negative impact on performance. The new work brings more evidence to this discussion. How easy or how hard a task is affects how much attention we pay to our surroundings.
[H/T: New Scientist]