Stress-related cortisol responsivity modulates prospective memory

It is known that there is inter-individual variation in behavioural and physiological stress reactions to the same stressor. The present study aimed to examine the impact of cortisol responsivity on performance in a complex real life-like prospective memory (PM) paradigm by a re-analysis of data published previously, with a focus on the taxonomy of cognitive dimensions of PM. Twenty-one male subjects were stressed with the Socially Evaluated Cold Pressor Test (SECPT) before the planning of intentions. Another group of 20 males underwent a control procedure. Salivary cortisol was measured to assess the intensity of the biological stress response. Additionally, participants rated the subjective experience of stress on a 5-point rating scale. Stressed participants were post-hoc differentiated in high (n = 11) and low cortisol responders (n = 10). Cortisol niveau differed significantly between the two groups, whereas subjective stress ratings did not. PM performance of low cortisol responders was stable across time and the PM performance of controls declined. High cortisol responders showed a nominally weaker PM retrieval across the early trails and significantly improved only on the last trial. The data demonstrate for the first time that participants with a low cortisol responsivity may benefit from stress exposure before the planning phase of PM. PM performance of high cortisol responders shows a more inconsistent pattern, which may be interpreted in the sense of a recency effect in PM retrieval. Alternatively, high cortisol responses may have a deteriorating effect on PM retrieval, which disappeared on the last trials of the task as a result of the decrease of cortisol levels across time. Importantly, the data also demonstrate that the intensity of cortisol responses does not necessarily correspond to the intensity of the mental experience of stress.

Real-life memory and spatial navigation in patients with focal epilepsy: ecological validity of a virtual reality supermarket task

Ecological assessment and training of real-life cognitive functions such as visual-spatial abilities in patients with epilepsy remain challenging. Some studies have applied virtual reality (VR) paradigms, but external validity of VR programs has not sufficiently been proven. Patients with focal epilepsy (EG, n=14) accomplished an 8-day program in a VR supermarket, which consisted of learning and buying items on a shopping list. Performance of the EG was compared with that of healthy controls (HCG, n=19). A comprehensive neuropsychological examination was administered. Real-life performance was investigated in a real supermarket. Learning in the VR supermarket was significantly impaired in the EG on different VR measures. Delayed free recall of products did not differ between the EG and the HCG. Virtual reality scores were correlated with neuropsychological measures of visual-spatial cognition, subjective estimates of memory, and performance in the real supermarket. The data indicate that our VR approach allows for the assessment of real-life visual-spatial memory and cognition in patients with focal epilepsy. The multimodal, active, and complex VR paradigm may particularly enhance visual-spatial cognitive resources.

Development of neural correlates of empathy from childhood to early adulthood: an fMRI study in boys and adult men

Although empathy is rooted early in life, the ability to understand and share the emotions of others continues to develop after childhood. Here, we aimed at exploring developmental changes in the neural mechanisms underlying empathy from childhood to early adulthood. Using functional magnetic resonance imaging, 47 healthy male subjects aged 8-27 years were investigated during an explicit empathy task. Emotional faces were presented and participants were either asked to infer the emotional state from the face (other-task) or to judge their own emotional response to the face (self-task). A perceptual decision on the width of faces was used as a control condition. Age-related activity increases were observed in the fusiform gyrus and inferior frontal gyrus, depending on whether subjects attributed emotions to self or other. During the self-task, activity in the right precuneus and right intraparietal sulcus decreased as a function of age. No age-related differences were observed in behavioral performance measures. Increased activity in the fusiform gyrus and in the frontal component of the human mirror neuron system with increasing age may be explained by greater experience and expertise accumulated during socio-emotional interactions. Greater recruitment of right parietal structures in younger as compared to older subjects might reflect developmental differences in the cognitive strategies to infer one's own emotional response. This study is the first to show developmental changes in the neural mechanisms supporting empathy. Our findings may have important implications for the development of novel therapeutic interventions in clinical conditions characterized by empathy deficits, such as autism spectrum disorder.