Mind-brain identity theory proposes that mental states are identical to brain states. One worry with this philosophy of mind is how a person can have mental states if the brain is just a lump of meat? Interestingly, the effect of this worry is very similar to a well-known phenomenon in developmental psychology – the ‘still-face effect’.

First reported in 1975 by Ed Tronick and colleagues, the still-face effect describes a type of event in which an infant, following three minutes of face-to-face ‘interaction’ with a non-responsive and expressionless (‘still-face’) mother, ‘rapidly sobers and grows wary. He makes repeated attempts to get the interaction into its usual reciprocal pattern. When these attempts fail, the infant withdraws [and] orients his face and body away from his mother with a withdrawn, hopeless facial expression.’

Perceiving the brain as a lifeless piece of matter, rather than the astonishing ‘wonder tissue’ it really is (in the words of Daniel Dennett), encourages aversion, as observed in the infant in interaction with the still-face parent. So, it seems as though there is a genuine ‘still-brain effect’. The irony in the worry is that the perception of the brain as inert is itself caused by brain activity. Would stating this fact to the worrier make any difference?