By George Dvorsky
The human brain is unquestioningly an amazing thing. But for all its strengths, it can be pretty glitchy at times. And indeed, as new research from Case Western Reserve has revealed, our brains have two very important functions that tend to work quite well — just not simultaneously. It turns out that when we’re being analytical, the empathetic parts of our brain shuts down, and vice versa. The insight may help to explain not just the limits to human cognition, but also what may be going wrong in the brains of people with social disorders.
According to new research by Anthony Jack and his colleagues, the brain contains two different networks that are in constant tension. Normally, when we’re not called upon to think too deeply or consider moral issues, our brains idle and toggle between two cognitive modes, what are called the social network and the analytical network.
So, when we do things like math or our personal accounting, we’re pulling from the analytical network. And when we’re thinking about the needs of others or certain ethical conundrums, we draw from the social network.
However, as Jack’s research has shown, the human brain has evolved a physiological constraint in its ability to engage both of these networks at the same time — networks that are both crucial to our understanding of the external world. When we’re called upon to do one or the other our brains shut down the network that’s not being used — what the researchers are calling a ‘neural constraint’ on account of two incompatible cognitive modes.
To prove that this is the case, Jack took 45 volunteers and asked each of them to take five 10-minute turns inside an fMRI machine. While their brains were being scanned and imaged, they were randomly presented with 40 written and 40 video problems that tested social cognition (reasoning about the mental states of other persons) and physical cognition (reasoning about the causal/mechanical properties of inanimate objects). The participants were also given periods to rest and not think about anything too deeply.
When the subsequent scans were analyzed, the researchers saw that social problems had shut down the analytical portion of the brain while the social network areas lit up. And vice versa when the analytical questions were presented. Essentially, the appropriate neural pathways lit up depending on which network was being called upon.
It’s worth noting that the study did not assess the participants’ ability to be compassionate while conducting analytical tasks; the neuroscientists were strictly looking at the physiological responses to their tests and making inferences based upon that.
The researchers say that the new insight could help explain such conditions as anxiety, depression, ADHD, and autism — conditions that tend to involve a social dysfunction of some sort. Future treatments may work to target a balance between the two networks.
And as for normal functioning people, the research could also explain why we might make poor moral decisions when having to work on a complex task — including such things as budgeting or performance assessments. And conversely, it’s also a reminder to set aside some quality “thinking time” when we have to consider the logic of our moral views. Read the entire study at NeuroImage.