Repeated study typically improves episodic memory performance. Two different types of explanations of this phenomenon have been put forward: (1) reactivating the same representations strengthens and stabilizes memories, or (2) greater encoding variability benefits memory by promoting richer traces. The present experiment directly compared these…

Some previous studies have shown that increased stress hormone levels have beneficial effects on memory encoding; however, there is no clear consensus on which encoding-related processes are affected by stress hormones. In the present study, we investigated the relationship between interindividual differences in neuroendocrine response to acute…

This study aimed to determine whether attentional prioritization of stimuli associated with reward transfers across conceptual knowledge independently of physical features. Participants successively performed two color-word Stroop tasks. In the learning phase, neutral words were associated with high, low, or no monetary reward. In the…

Phosphorylation of CaMKII and AMPA receptor GluA1 subunit has been shown to play a major role in hippocampal-dependent long-term/reference memory (RM) and in the expression of long-term synaptic potentiation (LTP). In contrast, it has been proposed that dephosphorylation of these proteins could be involved in the opposite phenomenon of hippocampal…

Stimuli conditioned with a substance can generate drug-approach behaviors due to their acquired motivational properties. According to implicit theories of addiction, these stimuli can decrease cognitive control automatically. The present study (n = 49) examined whether reward-associated stimuli can interfere with cognitive processes in the absence…

High sugar diets reduce hippocampal neurogenesis, which is required for minimizing interference between memories, a process that involves "pattern separation." We provided rats with 2 h daily access to a sucrose solution for 28 d and assessed their performance on a spatial memory task. Sucrose consuming rats discriminated between objects…

Hippocampal-dependent episodic memory and stimulus discrimination abilities are both compromised in the elderly. The reduced capacity to discriminate between similar stimuli likely contributes to multiple aspects of age-related cognitive impairment; however, the association of these behaviors within individuals has never been examined in an animal…

Balancing habitual and deliberate forms of choice entails a comparison of their respective merits--the former being faster but inflexible, and the latter slower but more versatile. Here, we show that arbitration between these two forms of control can be derived from first principles within an Active Inference scheme. We illustrate our arguments…

The prefrontal cortex (PFC) is known to be critically involved in strategy switching, attentional set shifting, and inhibition of prepotent responses. A central feature of this kind of behavioral flexibility is the ability to resolve conflicting response tendencies, suggesting a general role of the PFC in resolving interference. If so, the PFC…