Undergrad_Book_16-18_Pge_View_Print_no print marks_compressed

Undergraduate Research at UMass Dartmouth
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ternal sources of information, and therefore need to
continue to explore the ways in which they affect our
categorization of others into social and racial groups.
Categorical perception was tested through a typical
two-stage paradigm (reviewed by Fugate, 2013).
The first paradigm, classification (or identification),
defined a participant’s categorical boundary (i.e.,
the point at which an individual distinguishes an
image as either one race or another). The second
paradigm, discrimination, was used to test for the
hallmark of CP which is an increase in the ability to
discriminate between pictures previously assigned
to different categories compared with pictures previously
assigned to the same category, even though
the physical difference between the pictures is
always held constant.
During the classification stage of this research,
participants were presented with an array of racially
ambiguous face stimuli that have been created
using computer software (FantaMorph). These
faces were created by combining two photos of
different-race individuals and making systematic
blends (known as morphs) that depict iterations
between the two pictures. Participants were then
asked to identify each stimulus as belonging to one
of two categories, anchored by the picture endpoints
or race-related words in different trials. We used
several different race-related words to see whether
a person’s threshold changes when evoking different
race-related words and from when no words are
evoked (match to picture condition).
During the discrimination stage of this research,
participants were presented with two sequential
morphs, which either span the threshold (established
in part 1) or do not span the threshold (but
constitute the same structural difference between
the faces). The former trials were the “between-category”
trials. Participants’ increased accuracy to
discriminate better the “between-category” trials