Consciousness

(Tuis.) #1

  • seCtIon tHRee: BoDY AnD WoRLD
    James quotes Gustav Fechner suggesting that someone who focuses attention
    on something does not see its colour as brighter or its sound as louder, but ‘feels
    the increase [in intensity] as that of his own conscious activity turned upon the
    thing’ (James, 1890, i, p. 462). This idea was later adapted by phenomenologists,
    who explore the structures of consciousness from a first-person perspective.
    They stressed how attention moulds the structure of consciousness, for example
    into foreground and background or centre and periphery. This idea survives in
    recent accounts of how attention provides a kind of ‘experiential highlighting’
    that allows us to track, inspect, and act with respect to another person or object
    (Campbell, 2002).
    The metaphor of the spotlight has found a place in many scientific theories of
    mind, including Francis Crick’s ‘astonishing hypothesis’ (1994) and global work-
    space theory (e.g. Baars, 1997a, 1997b). Others have elaborated on the intuitive
    metaphor, giving us variants like the zoom-lens model (Eriksen and St  James,
    1986) and the blinking spotlight (VanRullen, Carlson, and Cavanagh, 2007) or
    doughnut-shaped spotlight (Müller and Hübner, 2002).
    These metaphors should not be taken too literally, and have often been criticised,
    for example on the grounds that attention simply improves access to, or deci-
    sion-making about, what is already represented ‘in’ visual consciousness. There
    has been much discussion of whether or not attention increases brightness con-
    trast, or merely improves the accuracy of our perceptions by making us process
    things more deeply (Prinzmetal et al., 2008). Ned Block has also argued that such
    changes in experience should be thought of as changing not the content of the
    experience but the nature of the ‘mental paint’ we apply when paying attention
    (Block, 2010).
    Yet experiments have found that the metaphor of ‘lighting up’ has a lit-
    eral basis: a real attentional ‘spotlighting’ effect in visual perception. Par-
    ticipants kept their eyes fixated on the fovea (where spatial resolution is
    highest) and were shown textures in the periphery (where it is much lower).
    When they attended to the textures (still not moving
    their eyes), they could more easily distinguish them
    (Yeshurun and Carrasco, 1998). It was as though their
    spatial resolution had improved. Crucially, in tasks
    where enhanced resolution actually makes the task
    harder, this effect was found for focused attention,
    too: participants’ performance got worse. Later exper-
    iments found that the same effect for brightness, con-
    trast, and colour saturation, but not for differences
    in hue (Fuller and Carrasco, 2006). It seems that, as
    in James’s notion of focalisation and concentration,
    attention actually increases the spatial resolution
    of what we see. It may also change visual and other
    sensory experience in different ways depending on
    context, so it seems that attention can qualitatively shape the kinds of con-
    scious experiences we have – even if, as James also pointed out, we know
    how to adjust for these effects so we are not misled into thinking the light
    actually just got brighter.


‘attention is


consciousness and


something more; [. . .]


it is consciousness


concentrated’


(Hamilton, 1895, p. 941)


FIGURE 7.1 • Attention feels like a searchlight
in the attic, lighting up now the
objects right in front of us, and
then some long-forgotten memory
from the darkest corner of our
mind.

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