Abstracts of the Psychonomic Society — Volume 14 — November ...

Saturday Morning Papers 197–198
display what appears to be an understanding of abstract domains, when
in fact performance is driven by similarity-based structural alignment
(i.e., analogy) to stored exemplars. Supportive simulations of animal,
infant, and adult learning are provided. We suggest that there is a high
degree of continuity across species and development in terms of learning
processes and representations.
11:20–11:35 (197)
Categorical Versus Trait-Based Dimensional Classification Systems
for Personality Disorders. BENJAMIN M. ROTTMAN &
WOO-KYOUNG AHN, Yale University, NANCY S. KIM, Northeastern
University, & CHARLES A. SANISLOW, Yale University (read by
Woo-Kyoung Ahn)—Features are inherently ambiguous in that their
meanings depend on the categories they describe (e.g., small for planets
vs. molecules; Murphy, 1988). However, a new proposal for the
upcoming revision of the Diagnostic and Statistical Manual of Mental
Disorders (DSM) advocates eliminating personality disorder categories,
instead describing patients using only dimensions with the well-known
five-factor model (FFM). In a series of studies, we investigated whether
practicing clinicians (N 5 378) and experts in personality pathology
(N 5 73) are able to translate dimensional, FFM-based patient descriptions
into their corresponding DSM diagnostic categories. The results
showed that both practicing clinicians and experts (personality disorder
30
researchers) had considerable difficulty disambiguating the meaning
of the dimensions to determine correct diagnoses. Participants also
found the dimensional system to be less useful for making prognoses
and devising treatment plans. Implications for categorization research
are discussed.
11:40–11:55 (198)
Are Jungle Ravens Birds? How Atypical Modifiers Create Doubt in
Generic Sentences. JAMES A. HAMPTON, City University London,
ALESSIA PASSANISI, University of Catania, & MARTIN L. JÖNS-
SON, University of Lund—When a generic statement (“Ravens are
black”) has its subject modified (“Jungle ravens are black”), confidence
in the truth of the statement goes down in proportion to the atypicality of
the modifier (Connolly et al., 2007). In a series of studies, we first replicated
the effect and its interaction with modifier typicality. Curiously,
we then found that the modifier effect did not interact with the centrality
of the property. Both central (“Ravens are birds”) and mutable (“Ravens
are black”) sentences were equally affected by an atypical modifier. Finally,
when a story context was provided to give credibility to the modified
concept, the effect was greatly reduced. We conclude that the effect
results from general uncertainty about the existence and reference of
unfamiliar noun phrases. Jungle ravens may be a subset of ravens, but
they may equally be a type of helicopter or the name of a rock band.