Chapter
Eight
Conscious and unconscious
concept (Murphy and Zajonc, 1993). One group of participants saw either a smil-
ing face or a scowling face for one second before each ideograph. They were told
to ignore these faces and concentrate only on rating the ideographs. The second
group were shown the faces for only 4 msec, which is not long enough to see
them. The striking result was that the first group managed to ignore the faces,
but the second group were influenced by the faces they claimed not to see. If the
invisible face was smiling they were more likely to rate the ideograph as ‘good’.
Outside the lab, such effects may permeate our complex social worlds as we
unconsciously imitate other people’s facial expressions, mannerisms, moods, and
tone of voice, or make spontaneous judgements about people without knowing
why. Many of these judgements depend on emotional signals that are difficult to
hide, and are interpreted remarkably fast and accurately (Choi, Gray, and Ambady,
2005). Other ‘implicit impressions’, however, are less reliable. For example, if pho-
tos of people with a distinctive physical feature are paired with positive or neg-
ative events, this affects subsequent responses to other people who have that
same physical feature. You may treat strangers more positively if they resemble
someone you love. There is also the phenomenon of spontaneous trait transfer-
ence, in which descriptions of a person’s traits are transferred to the person who
gave the description. For example, if you describe someone as kind and clever,
or cruel and devious, the listener may unconsciously attribute those characteris-
tics to you (Uleman, Blader, and Todorov, 2005), implying a ‘boomerang effect’ of
malicious gossip.
What is going on in the brain during unconscious or implicit perception? Stud-
ies have shown that both positive and negative faces can produce significant
changes in amygdala activation, even when the stimuli are not consciously per-
ceived (Williams et al., 2004). Using dichoptic colour fusion, Moutoussis and Zeki
(2002) made binocularly viewed face and house stimuli invisible and showed that
the relevant brain areas (the fusiform face area and parahippocampal place area,
respectively) were still activated, if less strongly, even when the stimuli were not
perceived. This finding could be interpreted in two quite different ways. Perhaps
at a certain level of activity the stimulus becomes conscious, or alternatively at
that level the activity starts to have other effects within the brain and body.
Stanislas Dehaene and his colleagues used ERPs (event-related potentials) and
fMRI to investigate how the presentation of numbers masked and presented
too briefly to be seen can help in subsequent processing of related numbers,
indicated by the speed of pressing a response key. They found activity in motor
as well as sensory areas, suggesting covert responses to the primes that could
not be reliably reported or discriminated. They concluded that ‘A stream of per-
ceptual, semantic, and motor processes can therefore occur without awareness’
(Dehaene et al., 1998, p. 597). This is reminiscent of William James’s contention
that ‘Every impression which impinges on the incoming nerves produces some
discharge down the outgoing ones, whether we be aware of it or not’ (1890, ii,
p. 372).
This brings us back to that troublesome ‘magic difference’ and the hunt for the
NCCs. If every impression produces effects in the brain, then what is the differ-
ence between the ones we are aware of and those we are not? In the following
section, we will face a similar question as it applies to the difference between
conscious and unconscious action.
‘there is still no
agreement as to the
role of unconscious or
preconscious cognitive
processes’(Merikle, 2007, p. 512)