You are not sensing in a dream but you can experiance the sensation of sensing.

In normal operation the brain works like this: senses -> identifying -> filtering -> puting into context -> reaction -> physical movment

But in a dream this is: memmory -> putting into context -> reaction -> mental movment

Even if you realy have no physical fealing in a dream the brain does not know that because it gets stimulated like normal.

It is worth mentioning that you are not recording memmory in a dream. All memmory is confined to about 3sec of real time dream, but since your brain is using a smaler part it works faster and 3sec feels like at least 5min.