Opponent appetitive-aversive neural processes underlie predictive learning of pain relief.
Termination of a painful or unpleasant event can be rewarding. However, whether the brain treats relief in a similar way as it treats natural reward is unclear, and the neural processes that underlie its representation as a motivational goal remain poorly understood. We used fMRI (functional magnetic resonance imaging) to investigate how humans learn to generate expectations of pain relief. Using a pavlovian conditioning procedure, we show that subjects experiencing prolonged experimentally induced pain can be conditioned to predict pain relief. This proceeds in a manner consistent with contemporary reward-learning theory (average reward/loss reinforcement learning), reflected by neural activity in the amygdala and midbrain. Furthermore, these reward-like learning signals are mirrored by opposite aversion-like signals in lateral orbitofrontal cortex and anterior cingulate cortex. This dual coding has parallels to 'opponent process' theories in psychology and promotes a formal account of prediction and expectation during pain.
Seymour
Ben
B
Wellcome Department of Imaging Neuroscience, 12 Queen Square, London WC1N 3BG, UK. bseymour@fil.ion.ucl.ac.uk
O'Doherty
John P
JP
Koltzenburg
Martin
M
Wiech
Katja
K
Frackowiak
Richard
R
Friston
Karl
K
Dolan
Raymond
R
D001362:Avoidance Learning / Q000502:physiology*; D001521:Behavior Therapy / Q000379:methods*; D001921:Brain / Q000098:blood supply / Q000503:physiopathology*; D002211:Capsaicin / Q000009:adverse effects; D003213:Conditioning, Psychological / Q000502:physiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008954:Models, Biological; D010100:Oxygen / Q000097:blood; D010146:Pain / Q000139:chemically induced; D059408:Pain Management; D010147:Pain Measurement / Q000379:methods; D012201:Reward; D018709:Statistics, Nonparametric; D013997:Time Factors
D002211:Capsaicin; D010100:Oxygen