Ambiguity aversion in schizophrenia: An fMRI study of decision-making under risk and ambiguity.
When making decisions in everyday life, we often have to choose between uncertain outcomes. Economic studies have demonstrated that healthy people tend to prefer options with known probabilities (risk) than those with unknown probabilities (ambiguity), which is referred to as "ambiguity aversion." However, it remains unclear how patients with schizophrenia behave under ambiguity, despite growing evidence of their altered decision-making under uncertainty. In this study, combining economic tools and functional magnetic resonance imaging (fMRI), we assessed the attitudes toward risk/ambiguity and investigated the neural correlates during decision-making under risk/ambiguity in schizophrenia. Although no significant difference in attitudes under risk was observed, patients with schizophrenia chose ambiguity significantly more often than the healthy controls. Attitudes under risk and ambiguity did not correlate across patients with schizophrenia. Furthermore, unlike in the healthy controls, activation of the left lateral orbitofrontal cortex was not increased during decision-making under ambiguity compared to under risk in schizophrenia. These results suggest that ambiguity aversion, a well-established subjective bias, is attenuated in patients with schizophrenia, highlighting the need to distinguish between risk and ambiguity when assessing decision-making under these situations. Our findings, comprising important clinical implications, contribute to improved understanding of the mechanisms underlying altered decision-making in patients with schizophrenia.
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Junya
J
Fujino
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Kimito
K
Hirose
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan; Institute of Applied Brain Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan; School of Human and Social Sciences, Tokyo International University, 2509 Matoba, Kawagoe, Saitama 350-1198, Japan.
Shisei
S
Tei
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Ryosaku
R
Kawada
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Kosuke
K
Tsurumi
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Noriko
N
Matsukawa
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Jun
J
Miyata
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Genichi
G
Sugihara
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Yujiro
Y
Yoshihara
Department of Psychology, Waseda University, 1-24-1 Toyama, Shinjuku-ku, Tokyo 108-8345, Japan.
Takashi
T
Ideno
Human Brain Research Center, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Toshihiko
T
Aso
Department of Psychology, Waseda University, 1-24-1 Toyama, Shinjuku-ku, Tokyo 108-8345, Japan.
Kazuhisa
K
Takemura
Human Brain Research Center, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Hidenao
H
Fukuyama
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan.
Toshiya
T
Murai
Department of Psychiatry, Graduate School of Medicine, Kyoto University, 54 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan. Electronic address: hidehiko@kuhp.kyoto-u.ac.jp.
Hidehiko
H
Takahashi
D000328:Adult; D001362:Avoidance Learning / Q000502:physiology*; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology*; D001931:Brain Mapping; D003657:Decision Making / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D012309:Risk-Taking; D012559:Schizophrenia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D035501:Uncertainty
Ambiguity; Decision-making; Functional magnetic resonance imaging; Orbitofrontal cortex; Risk; Schizophrenia