In fear differential conditioning, stimuli that resemble the conditioned stimulus (CS+) are more likely to trigger fear responses. Excessive fear responses on stimuli not like CS + are often associated with anxiety. However, the threat judgments process and how this process manifests itself differently in subgroups with different generalisation rule applications, is unclear. This study examines whether anxiety biases the threat decision process in fear generalisation paradigm and whether subgroups characterised by different generalisation gradients was interpreted differently by drift-diffusion (...) model. We gathered behavioural data through a binary fear generalisation judgment task and clustered participants based on their responses. Reaction time distributions and individual scale scores were analyzed using the hierarchical drift-diffusion model. The model results suggested that similarity and state anxiety facilitated evidence-gathering processes that favoured “threat” judgments, but at the same time, state anxiety weakened the effect of stimulus similarity as evidence. Further cluster analyses revealed that this effect of anxiety on threat judgments only held true for specific subgroups of participants. This pioneering computational modelling effort in fear generalisation underscores the significant role of strategy preference and its complex interaction with anxiety in shaping stimulus processing. (shrink)

Background: Studies of sexual conditioning typically focus on the development of conditioned responses to a stimulus that precedes and has become associated with a sexual unconditioned stimulus (US). Such a sexually conditioned stimulus (CS) provides the opportunity for feed-forward regulation of sexual behavior, which improves the efficiency and effectiveness of the sexual activity. Objective and Design: The present experiments were conducted to provide evidence of such feed-forward regulation of sexual behavior in laboratory studies with domesticated quail by (...) measuring how many fertilized eggs were produced by the female after the sexual encounter. During the conditioning phase, male and female quail received a conditioned stimulus paired with the opportunity to copulate with each other. Results: Sexual conditioning increased the number of eggs that were fertilized as a consequence of copulation, especially if both the male and the female were exposed to the sexual CS. This conditioned fertility effect occurred with a range of CS durations and CS types. The conditioned fertility effect also occurred in situations involving sexual competition. When two males copulated with the same female, DNA fingerprinting showed that the male whose sexual encounter was signaled by a sexual CS was responsible for most of the resulting offspring. Sexual conditioning also reduced the first-male disadvantage in fertilization that occurs when two males copulate with the same female separated by several hours. Another significant finding was that sexual conditioning attenuated the usual drop in fertilization rate that occurs when the same male copulates with two females in succession. Conclusion: These results show that sexual conditioning increases the number of offspring that are produced in both isolated male-female encounters and in situations that involve two males copulating with the same female or one male copulating with more than one female. By increasing fertilization rates, sexual conditioning can alter genetic transmission across generations and shape evolutionary change. Keywords: sexual conditioning; sexual learning; conditioned fertility; sexual competition; quail; pavlovian conditioning (Published: 15 March 2012) Citation: Socioaffective Neuroscience & Psychology 2012, 2 : 17333 - DOI: 10.3402/snp.v2i0.17333. (shrink)