Hearing loss and perceptual effort: Downstream effects on older adults' memory for speech

A group of older adults with good hearing and a group with mild-to-moderate hearing loss were tested for recall of the final three words heard in a running memory task. Near perfect recall of the final words of the three-word sets by both good- and poor-hearing participants allowed the inference that all three words had been correctly identified. Nevertheless, the poor-hearing group recalled significantly fewer of the nonfinal words than did the better hearing group. This was true even though both groups were matched for age, education, and verbal ability. Results were taken as support for an effortfulness hypothesis: the notion that the extra effort that a hearing-impaired listener must expend to achieve perceptual success comes at the cost of processing resources that might otherwise be available for encoding the speech content in memory.     

Newborns modulate their crawling in response to their native language but not another language

Human newborns can propel themselves to their mother's breast when positioned skin to skin on her abdomen just after birth. For decades, researchers have considered this primitive crawling behavior a spinal reflex, immune to supra spinal control. However, recent research suggests that neonatal crawling is already responsive to visual and olfactory stimuli processed at a supra spinal level. Here we report that a few hours post birth, French newborns can also modulate their crawling in response to their native language – a source of information that is processed supra-spinally. The crawling patterns of 23 French-born newborns were recorded on video and via an infrared motion capture system during two randomly ordered 2-min trials. The newborns were secured on a mini skateboard to facilitate arm and leg movements during their crawling propulsion. They heard a repetitive sequence of the same sentences either in French, their native language, or in English, a rhythmically different and hence discriminable unfamiliar language, on each trial. In French, compared to English, crawling was enhanced, with significantly more arm and leg steps and significantly more and larger trunk rotations in the cephalo-caudal axis. Moreover, newborns rotated their heads and trunk toward the appropriate loud speaker when hearing French but not English. These preliminary findings suggest that newborn crawling is not a simple stereotyped reflex under spinal control, but a complex pattern that can be modulated in response to higher-order, supra-spinally processed stimuli. The findings open fascinating questions about the range of stimuli to which newborn crawling is responsive.     

Effects of sad mood on time-based prospective memory

Very little is known about the influence of emotional factors on prospective memory (PM) performance. We used a mood induction (neutral or sad) to examine the effects of sad mood on time-based PM performance. Based on Ellis and Ashbrook's (1988) resource allocation model, we hypothesised an adverse effect of sad mood on PM performance. Results revealed that participants who responded to the sad mood induction procedure showed reduced PM performance that mainly resulted from a decreased timeliness of PM responses, but only in the first half of the task. Mood effects on PM could be explained in terms of reduced and less accurate monitoring. Implications for concepts of PM and the assessment of emotional after-effects are discussed.