Perceiving
faces can be enhanced by touch, says researcher Kazumichi Matsumiya of Tohoku
University in Japan.
The face
aftereffect
In a series
of studies, Matsumiya took advantage of a phenomenon called the “face
aftereffect” to investigate whether our visual system responds to nonvisual
signals for processing faces.
In the face
aftereffect, we adapt to a face with a particular expression — happiness, for
example — which causes us to perceive a subsequent neutral face as having the
opposite facial expression (i.e., sadness).
Matsumiya
hypothesized that if the visual system really does respond to signals from
another modality, we should see evidence for face aftereffects from one
modality to the other. So, adaptation to a face that is explored by touch should
produce visual face aftereffects.
The
experiment
To test
this, Matsumiya had participants explore face masks concealed below a mirror by
touching them. After this adaptation period, the participants were visually
presented with a series of faces that had varying expressions and were asked to
classify the faces as happy or sad. The visual faces and the masks were created
from the same exemplar.
In line
with his hypothesis, Matsumiya found that participants’ experiences exploring
the face masks by touch shifted their perception of the faces presented
visually compared to participants who had no adaptation period, such that the
visual faces were perceived as having the opposite facial expression.
Further
experiments ruled out other explanations for the results, including the
possibility that the face aftereffects emerged because participants were
intentionally imagining visual faces during the adaptation period.
And a
fourth experiment revealed that the aftereffect also works the other way:
Visual stimuli can influence how we perceive a face through touch.
No comments:
Post a Comment