For many men, this can happen several times a day because this is autopilot behaviour for the male brain.They don't think it's a big deal and they can't understand why women find it so threatening - until the tables are turned.
It is the classic complaint: men accuse women of being too emotional and women accuse men of not being emotional enough.
Each thinks the other could just decide to be different - if they really wanted to.
But the brain circuitry for emotional processing is different in men and women.
Until recently, the chasm between how men and women feel and express emotions was thought to be due to upbringing.
But while culturally females may consider men to be rather simple creatures, nothing could be further from the truth.
My clinical work and research as a neuropsychiatrist and professor of clinical psychiatry, in fields from neuroscience to evolutionary biology, convinced me that the unique brain structures of men create a male reality, fundamentally different from the female one. You're chatting to your partner in a cafe when you catch him salivating over your shoulder at a buxom 20-something. Like it or not, the lust centre in the male brain automatically directs men to visually take in the details of attractive females.To your partner's brain, the buxom woman was like a colourful hummingbird.She flew into his line of vision, caught his attention for a few seconds, then flew off, out of his mind.Of course, how parents raise us can reinforce or suppress parts of our biology, but we now know that the emotional processing in the male and female brain is not the same.Research suggests that our brains have two emotional systems that work simultaneously: system or MNS (which allows us to emotionally empathise with people); and the parietal junction system or TPJ (which fires the brain's analyse-and-fix-it circuits to look for solutions to emotional problems - cognitive empathy). This prevents their thought processes from being clouded by emotions, strengthening their ability to find practical solutions, but at times, it can make them appear to be uncaring.Male or female, when we see an emotion on someone else's face, our MNS (emotional empathy system) activates.