we start to inhabit their emotional space;

[keannu]

When we see a happy face (or an angry one), it subtly generates the corresponding emotion in us. To the degree we take on the pace, posture, and facial expression of another person, we start to inhabit their emotional space; as our body mimics the other’s, we begin to experience emotional matching. Our nervous system is automatically set to engage in this emotional empathy. But how well we use this capacity is largely a learned ability. Animals－and people－who have been raised in extreme social isolation are poor at reading emotional cues in those around them not because they lack the basic circuitry for empathy but because, lacking emotional tutors, they have never learned to pay attention to these messages and so haven’t practiced this skill.

What does this mean? Does it mean "we imitate or follow others' emotions"? It's really hard to understand.
we start to inhabit their emotional space;

 

[emsr2d2]

It means that we are able to put ourselves in the emotional position of the person we are looking at and, as a result, we start to copy them. I think I've heard this referred to as "mirroring".

 

[keannu]

Is mimicking others' emotions same as empathy? Does it mean we understand others' emotions or just imitate them?

 

[Raymott]

Yes, it's called mirroring in psychology. No, it's not exactly imitation, which is a conscious action. This is an instinctual evolutionary behaviour. Babies smile when mothers smile, and vice versa. But the emotional mirroring refers more to feeling happy (or whatever the emotion is - fear, hatred, etc) rather than just to the external sign (a smile or frown, etc.)

I'm not sure whether it is learned (as you paragraph states) or whether it's entirely instinctual. It's probably an instinctual pattern that needs triggering and some reinforcement, but that's not an argument about English.
https://en.wikipedia.org/wiki/Mirroring_(psychology)

 

[keannu]

Does this mean that physical imitation can trigger emotional empathy? If you imitate someone's behaviors, can you also sympathize with their feelings? I can't get it, especially the meaning of "to the degree".

To the degree we take on the pace, posture, and facial expression of another person, we start to inhabit their emotional space; as our body mimics the other’s, we begin to experience emotional matching.

 

[emsr2d2]

To the same degree that we take on the pace, posture, and facial expression of another person, we also start to inhabit their emotional space; as our body mimics the other’s, we begin to experience emotional matching.

Does adding the words in red above help?

I read it the same way you do. If we copy someone physically, we start to find that we feel how they feel. Those things happen to the same degree (the same strength). Presumably, if we copy someone 100%, we should be able to completely empathise with them. If we copy them to, say, a 70% degree, then we are only likely to empathise with them 70% too.

 

[Raymott]

I think there's a problem with the word 'start' which could confuse the meaning.
I can see that there might be a similarity between the degree we "take on ..." and the degree "we inhabit their emotional space".