Stroke survivors tune people out but not necessarily for the reason you think. When I am struggling with a task I start talking to myself. When I hear my hemiplegic foot scuffing the floor because I am not lifting my leg high enough I start silently saying "knee up, knee up." If someone is talking to me at that moment I do not hear what that person is saying. I cannot listen to someone while I am talking myself through a task that able-bodied people do without any thought. For a stroke survivor multitasking can be walking and talking at the same time.
After twelve years of living with a stroke the only magic bullet I have found is to stop multitasking. If you want me to process new information or I want to participate in a discussion, I need to sit down. Eliminating multitasking is a magic bullet because it has an immediate effect. By not dividing my attention, I can focus all my energy on the part of my brain I need right now.
I do not feel bad about not multitasking. This strategy keeps me safe and improves my performance. When I take a hot dish out of the the oven I stop talking to guests. I need to make sure my hemiplegic (paralyzed) hand maintains a firm grip on the 400 degree handle. When I drive during rush hour I turn off the radio. I need to respond quickly to aggressive, unpredictable, impatient drivers. .
I am not saying stroke survivors can never multitask. However, it takes many repetitions before a task becomes so automatic that I can pay attention to a second task. After a month of winter I can zip my coat AND talk to friends as we get up to leave a restaurant.