In The Year of Magical Thinking, Joan Didion describes the year following the sudden death of her husband. At one point, while collecting his clothes for donation, she stops. She can't give away all of his shoes, for he might need them if he returns. This is the magical thinking of the title.
When people die, they're not completely gone. They live on in our minds. We might wonder what they think of our decisions, or we might carry on imaginary conversations with them. They are as alive to us as someone who just stepped out of the room.
The continued representation of the dead in our heads may contribute to afterlife beliefs (see chapter 5 of my new book The 7 Laws of Magical Thinking). You can't fully convince yourself that the person is kaput; your brain isn't wiped clean so easily. In one study by Jesse Bering, even people who said the soul dies when the body does continued to assign mental states to a fictional character after his death. One subjected noted that of course there's no afterlife and the dead character sees that now. So "out of sight, out of mind" isn't quite right when describing the departed. More like "out of sight, so the mind fills in the blanks."
But what if the person is still in sight? What do we think of people in persistent vegetative states, who can breathe but can't think? Mentally, they are dead, but since we're very aware of the body still lying there, we can't as easily imagine them as active characters in our lives. This combination of factors -- a dead mind but a living body -- may, ironically, lead us to think of people in a PVS as more dead than dead.
Kurt Gray, T. Anne Knickman, and Daniel Wegner recently tested this hypothesis and wrote up their findings in the journal Cognition. In the first study, subjects were divided into three groups and read about a character named David who had a car accident and then A) fully recovered, B) died, or C) ended up in a PVS with nearly his entire brain destroyed. Each group rated whether he had mental functions -- whether he could have a personality or know right from wrong, etc. -- on a scale from -3 (strongly disagree) to 3 (strongly agree). On average, living David scored 1.77, and dead David scored -0.29. But PVS David scored -1.73. People saw him as having less mind than dead David. So in a sense they saw PVS David as more dead than dead. But you could also say they saw dead David as not fully dead. The fact that they didn't deny him a mind as much as they could have, the authors argue, indicates subtle afterlife beliefs.
In the second study, the researchers asked people about PVS David, dead David, or a dead David whose description mentioned his embalmed body lying in a coffin. Again, subjects -- including both the most religious third and the least religious third -- saw PVS David as having less mental capacity than dead David. But the least religious saw corpse David as being similar to PVS David (they strongly disagreed with his having a mind), whereas the most religious saw him as being similar to dead David (they slightly agreed with his having a mind). For those low in religiosity, a focus on his nonfunctional physical body helped them recognize the nonfunctionality of his mind, just as the image of a PVS David in a hospital bed did. The most religious subjects, however, had explicit beliefs about the afterlife that allowed them to overcome the corpse reminder and continue to picture David frolicking in heaven or wherever.
In the third study, subjects imagined themselves in a car crash, and either dead or in a PVS. They said they'd have less mind in a PVS, and also that being in a PVS would be worse for both themselves and their families. Further, the attribution of less mind partially explained the greater undesirability of a PVS. People see being a vegetable as a state worse than death, in part because they irrationally believe they'd have a fuller mental life if someone just pulled the plug. (Of course, their mental lives would be equally nonexistent.)
"These data do highlight one irony," the researchers note: "People high in religiosity are more likely to see PVS as worse off than death, but are also more likely to advocate keeping such patients alive on life support."
They also point out that focusing on the body interferes with attribution of mind in everyday life, too. The more you objectify someone (a woman in a bikini, say), the less capable you think she is of thought.
So I guess if you really really want to excise someone's offensive personality from your memories, picture her (or him) as a corpse in a bikini. Don't be alarmed, however, if the image results in a little mental scarring.