How fast do your neuron synapses make connections when you learn something or create a memory



As far as I understand brain mostly works through network of neurons connected via synapses.

Now when you learn something new or create a memory then new connections should be created between some neurons to accommodate that info.

How fast those connections form? Minutes, seconds?

Say for example, someone tells you their name then how fast does your neurons connections are created/change to record their face and name and the association between them?

In: Biology