Research Report
Electrophysiological difference between mental state decoding
and mental state reasoning
Bihua Cao
a, 1
, Yiyuan Li
b, 1
, Fuhong Li
a, c,
⁎
, Hong Li
a, c,
⁎
a
Research Center for Psychological Development and Education, Liaoning Normal University, Dalian, 116029, China
b
School of Psychology, Southwest University, Chongqing, 400715, China
c
Key Laboratory of Cognition and Personality (SWU), Ministry of Education, 400715, China
ARTICLE INFO ABSTRACT
Article history:
Accepted 6 May 2012
Available online 14 May 2012
Previous studies have explored the neural mechanism of Theory of Mind (ToM), but the
neural correlates of its two components, mental state decoding and mental state reasoning,
remain unclear. In the present study, participants were presented with various photographs,
showing an actor looking at 1 of 2 objects, either with a happy or an unhappy expression.
They were asked to either decode the emotion of the actor (mental state decoding task),
predict which object would be chosen by the actor (mental state reasoning task), or judge at
which object the actor was gazing (physical task), while scalp potentials were recorded.
Results showed that (1) the reasoning task elicited an earlier N2 peak than the decoding task
did over the prefrontal scalp sites; and (2) during the late positive component (240–440 ms),
the reasoning task elicited a more positive deflection than the other two tasks did at the
prefrontal scalp sites. In addition, neither the decoding task nor the reasoning task has no
left/right hemisphere difference. These findings imply that mental state reasoning differs
from mental state decoding early (210 ms) after stimulus onset, and that the prefrontal lobe
is the neural basis of mental state reasoning.
© 2012 Elsevier B.V. All rights reserved.
Keywords:
Mental state reasoning
Prefrontal lobe
Theory of mind
1. Introduction
Theory of mind (ToM) refers to the ability to understand or
predict the behavior of others by inferring internal mental
states, such as beliefs, desires, and emotions (Premack and
Woodruff, 1978; Wellman, 1990; Wellman and Gelman, 1992).
Tager-Flusberg and Sullivan (2000) proposed that the ToM
includes social–cognitive and social–perceptual components.
Based on this componential view, Sabbagh and others
proposed a more functional perspective, in which ToM
reasoning is separated into at least a 2-stage process: mental
state decoding and mental state reasoning. In the initial stage,
relevant cues are decoded. In the second stage, the decoded
information is used to reason about mental states (Njomboro
et al., 2008; Sabbagh, 2004, 2006).
Mental state decoding is often studied using classic para-
digms, such as the “reading the mind in the eyes” test (Baron-
Cohen et al., 1997, 2001) and the “facial emotion identification”
task (Adolphs, 2002; Germine and Hooker, 2011; Haxby et al.,
2000, 2002; Sabbagh, 2004; Sommer et al., 2008; Vuilleumier
BRAIN RESEARCH 1464 (2012) 53– 60
⁎ Corresponding authors at: Research Center for Psychological Development and Education, Liaoning Normal University, Dalian, 116029,
China. Fax: +86 411 82159177.
E-mail addresses: fuhongli@swu.edu.cn (F. Li), lihongwrm@vip.sina.com (H. Li).
1
These authors contributed equally to this work.
0006-8993/$ – see front matter © 2012 Elsevier B.V. All rights reserved.
doi:10.1016/j.brainres.2012.05.009
Available online at www.sciencedirect.com
www.elsevier.com/locate/brainres