This answer is honestly playing very hard into gender stereotypes.

@Obie2.0 if it had sourced these claims I’d be less wary, but as it is, it seems to be telling this man to act submissive. Without knowing more about the science behind this technique, I don’t think we can simply claim that it’s following stereotypes.

@Tim - "Women get startled and shocked pretty easily." With a possible subtext of "Better avoid talking to them because who knows what could happen".

Besides which the advice basically is to do weird things like nibbling one's thumbnail whenever the co-worker walks by the OP, with the aim of looking like "an idiot" (the poster's words). That seems counterproductive, to say the least.

@com.prehensible can you give some scientific evidence that it would work? The onus is on you to show it does work, not us to show it doesn’t.

@Obie2.0 you’re twisting words here. The aim is to avoid startling / scaring someone, not to act like an idiot. Com is saying it’s better to end up looking like an idiot than end up scaring someone, but it’s certainly not the aim.

That's a terrible characterization of the study that you linked. Besides the difficulties in reaching psychological conclusions (which the study notes, sayig that "sex differences in brain activity in the absence of behavioral differences have been observed in a number of cognitive domains"), it's mostly assessing emotional memory, and notes that "anxiety levels were within a normal range here with no differences between women and men" and notably that "the neural differences across men and women were not accompanied by differences in picture responding or memory performance."

I didn't tell him to slap his mouth like he had told a lie. That is what children do in behavioural science. That would be silly indeed Obie 2.0. I suggested to try nail biting which communicates a need for reassurance, and is also called "pacyfying" gesture. the OP clearly requires to reassure and pacify this previously friendly colleague. Do you think that manually masturbating at work is more of a male behaviour or is it equally female? Are stereotypes of no use? Do women grow beards and have twice the muscle mass of men? do men wear make-up? make-up behaviour stereotypes are wrong?

I didn't say that the The OP can try wearing lipstick and mascara for work and wear it if he has to deliver documents to the girl. Although it is a funny idea.

I don't know what sex has twice the average muscle mass of women, but it sure isn't men, since they have like no more than 40% more based on body weight and muscle percentage ratios. Maybe Klingons?

You are interpreting what I wrote with over-litteral negativity.Women startle more easily than men, in the context of sexual threat, like knowing a man that confidently masturbates at work. Women fall into many categories from "I woke up at a party and three men were masturbating presque over my head and i didn't mind at all" to "I haven't put that thing in my mouth in 30 years of marriage George, I had never never heard of a blow job, it's ludicrous"...

Some people are naturally less proficient at human behaviour Obie, and even simple stuff will seem contrary to their expectations, like data in star wars who says "please explain to me what emotions are" if the topic is that alien to you, you should try it for yourself, what is the opposite of flashing a woman ? raising your hand to your mouth. and avoiding eye contact. He should behave like a reformed flashed, that's all i'm alluding to.

“Women get startled and shocked pretty easily from sexual threats like flashers.” - This is incredibly sexiest.

I have never crossed paths with a male who looks like he is panicked on a country walk, that is what I mean. Where I live, 97 % of the rural cyclists are males. The women are too scared in France with the current modern culture clashes. 90% of women are simply too threatened to take a bike in the countryside. In town it's 50% in the countryside it's 97% male cyclists.

Your opinion is ridiculous to me because My cousins came running home crying after they saw a farmer pissing in the field with his penis out, they said he was a flasher, and they were very alarmed. Can you imagine a man running away crying if he sees a woman squatting in a field? Why do you think that they don't get shocked?

-1 This answer made me blush

I had to change the answer to be unnecessarily detailed because people said idiotic things which are characteristic of scientific autism, and have little bearing on human and animal psychology. I bet you that If i stuck a camera on my head and took a walk through town, we could count about 25 percent of women that go past me put their hand up to their mouth for no reason. I don't ask them to, they do, and boys don't. people are different.