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Two correlates of outcome processing in the orbitofrontal cortex (OFC) have been proposed in the literature: One hypothesis suggests that the lateral/medial division relates to representation of outcome valence (negative vs. positive), and the other suggests that the medial OFC maintains steady stimulus-outcome associations, whereas the lateral OFC represents changing (unsteady) outcomes to prepare for response shifts. These two hypotheses were contrasted by comparing the original with the inverted version of the Iowa Gambling Task in an event-related functional magnetic resonance imaging experiment. Results showed (1) that (caudo) lateral OFC was indeed sensitive to the steadiness of the outcomes and not merely to outcome valence and (2) that the original and the inverted tasks, although both designed to measure sensitivity for future outcomes, were not equivalent as they enacted different behaviors and brain activation patterns. Results are interpreted in terms of Kahneman and Tversky's prospect theory suggesting that cognitions and decisions are biased differentially when probabilistic future rewards are weighed against consistent punishments relative to the opposite scenario [Kahneman, D., & Tversky, A. Choices, values, and frames. American Psychologist, 39, 341-350, 1984]. Specialized processing of unsteady rewards (involving caudolateral OFC) may have developed during evolution in support of goal-related thinking, prospective planning, and problem solving.
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INTRODUCTION: Learning processes like classical conditioning are involved in mediating sexual behavior. Yet, the neural bases underlying these processes have not been investigated so far. AIM: The aim of this study was to explore neural activations of classical conditioning of sexual arousal with respect to sex differences and contingency awareness. METHODS: In the acquisition phase, a geometric figure (CS+) was presented for 8 seconds and was followed by highly sexual arousing pictures (UCS), whereas another figure (CS-) predicted neutral pictures. Ratings and contingency awareness were assessed after the entire conditioning procedure. Forty subjects (20 females) were classified into one of four groups according to their sex and the development of contingency awareness (aware females, aware males, unaware females, and unaware males). MAIN OUTCOME MEASURES: Blood oxygen level dependent (BOLD) responses measured by functional magnetic resonance imaging (fMRI), skin conductance responses (SCRs), and subjective ratings. RESULTS: fMRI analysis showed two effects (awareness and sex) when comparing CS+ with CS-: (i) aware compared to unaware subjects showed enhanced differentiation (e.g., ventral striatum, orbitofrontal cortex, occipital cortex); and (ii) men showed increased activity compared to women in the amygdala, thalamus, and brainstem. CS+ and CS- ratings differed in aware subjects only. However, no conditioned SCRs occurred in any group. CONCLUSION: The increased activity in men is in line with theories postulating that men are generally more prone to conditioning of sexual arousal. Further, contingency awareness seems to be an important factor in appetitive learning processes, which facilitates conditioning processes.
Erkunden
Team
- Vaitl (2)
Eintragsart
Sprache
- Englisch (2)
Thema
- Frontal Lobe/physiology
- Adult (1)
- Amygdala/physiology (1)
- Arousal/*physiology (1)
- Awareness/physiology (1)
- Basal Ganglia/physiology (1)
- Brain Stem/physiology (1)
- Cerebral Cortex/*physiology (1)
- Choice Behavior/*physiology (1)
- Conditioning, Classical/physiology (1)
- Decision Making/physiology (1)
- Female (2)
- Functional Laterality/*physiology (1)
- Galvanic Skin Response (1)
- Gyrus Cinguli/physiology (1)
- Humans (2)
- Magnetic Resonance Imaging (1)
- Male (2)
- Occipital Lobe/physiology (1)
- Psychomotor Performance/physiology (1)
- Reaction Time/physiology (1)
- Sex Characteristics (1)
- Sexual Behavior/*physiology (1)
- Thalamus/physiology (1)
- Young Adult (1)