- seCtIon FIVe: BoRDeRLAnDs
Some coverage of #thedress suggested that it might prompt an ‘existential crisis’
about the nature of vision and reality, and many people described having argu-
ments about it, feeling freaked out by it, wondering ‘is my brain tricking me?’ and
‘is it a conspiracy?’
These phenomena bring us back to all the familiar philosophical problems
involved in what it means to see, and to the central problem of consciousness:
the difference between the objective and subjective worlds. In particular, they
return us to the idea that we may be so seriously mistaken about consciousness
that we should think of it as a grand illusion or as something that does not exist in
the form we usually take it to (Chapter 3). Perhaps it may help to learn about other
strange experiences that hover between reality and imagination.REALITY DISCRIMINATION
In everyday life, we discriminate ‘real’ from ‘imagined’ all the time without noticing
the skill involved. That is, we distinguish our own thoughts from what we assume
to be a public reality independent of those thoughts – a skill called reality mon-
itoring (Johnson and Raye, 1981) or reality discrimination. Experiments in which
people are asked to see or hear some stimuli, and to imagine others, show that
many different features can be used for the purpose of discrimination, including
how stable, detailed, or vivid the experiences are, and whether they can be vol-
untarily controlled. One study (Garrison et al., 2017) presented participants with
either complete or incomplete well-known word pairs (‘Laurel and Hardy’ or ‘Eggs
and. . .’) and tested how well they remembered which words were actually pre-
sented and which needed completing imaginatively: visual presentation resulted
in better reality monitoring than auditory presentation, and speaking the words
out loud worked better than internally verbalising (‘thinking’ about) them.
By and large, mental images are less richly detailed, less stable, and more easily
manipulated than perceptions. So we don’t usually confuse the two. We can, how-
ever, be tricked. In her century-old classic experiment, Cheves Perky (1910) asked
participants to look at a blank screen and to imagine an object on it, such as a
tomato. Unbeknown to them, she back-projected a picture of a tomato onto the
screen, and gradually increased the brightness. Even when the picture was bright
enough to be easily seen, the participants still believed that they were imagining
it. This effect is the reverse of hallucinations, in which we think something is there
when it isn’t. In this case, Perky’s participants were tricked into thinking there was
nothing there when there was. Similar effects have been found since, and show
that reality discrimination is affected by whether we expect something to be real
or imagined.
Distinguishing memories of events that really happened from events we have
only imagined is particularly difficult, and its failure results in false memories –
that is, convincing ‘memories’ of events that never actually happened. These can
be created when we tell the same story many times, with slight variations, and
then remember the last version we told. The latest version retroactively interferes
with the original memory. False memories can also be created when a family story
keeps being told or a photograph from childhood convinces you that you can
remember that day on the beach. And they can have lasting effects on behaviour.
For example, when people were told that they had had positive or negative