Wetbrain: the mind/brain of a person, sometimes refers to the person as a whole, who has become so saturated with alcohol that s/he can no longer communicate at all.

Examples..
1. She has wetbrain.
2. She’s a wetbrain.

No longer communicate, from what I’ve observed, means that the person may be able to articulate, possibly, but that the phrases don’t apply to the conversation.
I’m not sure if it’s because the person is time delayed and responding to a previous long finished conversation (possibly from days past) or if the person is talking to their own reality (which is not currently connected with the dominant reality) or if the person has some sort of aphasia.