A genetically mediated bias in decision making driven by failure of amygdala control.
Genetic variation at the serotonin transporter-linked polymorphic region (5-HTTLPR) is associated with altered amygdala reactivity and lack of prefrontal regulatory control. Similar regions mediate decision-making biases driven by contextual cues and ambiguity, for example the "framing effect." We hypothesized that individuals hemozygous for the short (s) allele at the 5-HTTLPR would be more susceptible to framing. Participants, selected as homozygous for either the long (la) or s allele, performed a decision-making task where they made choices between receiving an amount of money for certain and taking a gamble. A strong bias was evident toward choosing the certain option when the option was phrased in terms of gains and toward gambling when the decision was phrased in terms of losses (the frame effect). Critically, this bias was significantly greater in the ss group compared with the lala group. In simultaneously acquired functional magnetic resonance imaging data, the ss group showed greater amygdala during choices made in accord, compared with those made counter to the frame, an effect not seen in the lala group. These differences were also mirrored by differences in anterior cingulate-amygdala coupling between the genotype groups during decision making. Specifically, lala participants showed increased coupling during choices made counter to, relative to those made in accord with, the frame, with no such effect evident in ss participants. These data suggest that genetically mediated differences in prefrontal-amygdala interactions underpin interindividual differences in economic decision making.
Roiser
Jonathan P
JP
Institute of Cognitive Neuroscience, University College London, London WC1N 3AR, UK.
de Martino
Benedetto
B
Tan
Geoffrey C Y
GC
Kumaran
Dharshan
D
Seymour
Ben
B
Wood
Nicholas W
NW
Dolan
Raymond J
RJ
D000328:Adult; D000679:Amygdala / Q000098:blood supply / Q000502:physiology*; D000704:Analysis of Variance; D015982:Bias; D001931:Brain Mapping; D003657:Decision Making / Q000502:physiology*; D005260:Female; D005838:Genotype; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D010551:Personality / Q000235:genetics; D011601:Psychophysics; D011930:Reaction Time / Q000235:genetics; D012044:Regression Analysis; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics* / Q000502:physiology; D055815:Young Adult
C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D010100:Oxygen