The Influence of Emotional Material on Encoding and Retrieving Intentions: An ERP Study in Younger and Older Adults

Prospective memory is a cognitive process that comprises the encoding and maintenance of an intention until the appropriate moment of its retrieval. It is of highly relevance for an independent everyday life, especially in older adults; however, there is ample evidence that prospective memory declines with increasing age. Because most studies have used neutral stimuli, it is still an open question how emotional factors influence age-related differences in prospective remembering. The aim of the study was to investigate the influence of emotional material on prospective memory encoding, monitoring, maintaining, and retrieval in younger and older adults using behavioral and electrophysiological measures. We tested 24 younger adults (M = 26.4 years) and 20 older adults (M = 68.1 years) using a picture one-back task as ongoing activity with an embedded prospective memory instruction. The experimental task consisted of three sessions. In each session, participants had to encode series of images that represented the prospective memory cues for the consecutive block. The images were either of pleasant, unpleasant, or neutral valence. The pictures used in the ongoing task were likewise of pleasant, unpleasant, or neutral valence. Event-related potentials (ERPs) were recorded to assess the neural correlates of intention encoding, maintenance, and self-initiated retrieval. We did not find age differences between younger and older adults on the behavioral level. However, the ERP results revealed an interesting pattern that suggested for both age groups elevated attentional processing of emotional cues during encoding indicated by an elevated LPP for the emotional cues. Additionally, younger adults showed increased activity for unpleasant cues. During the maintenance phase, both age groups engaged in strategic monitoring especially for pleasant cues, which led to enhanced sustained positivity. During retrieval, older adults showed increased activity of ERP components related to cue detection and retrieval mainly for pleasant cues indicating enhanced relevance for those cues. In conclusion, emotional material may influence prospective remembering in older adults differently than in younger adults by supporting a mixture of top-down and bottom-up controlled processing. The results demonstrated a negativity bias in younger adults and a positivity bias in older adults

Electrophysiological Correlates of Strategic Monitoring in Event-Based and Time-Based Prospective Memory

Prospective memory (PM) is the ability to remember to accomplish an action when a particular event occurs (i.e., event-based PM), or at a specific time (i.e., time-based PM) while performing an ongoing activity. Strategic Monitoring is one of the basic cognitive functions supporting PM tasks, and involves two mechanisms: a retrieval mode, which consists of maintaining active the intention in memory; and target checking, engaged for verifying the presence of the PM cue in the environment. The present study is aimed at providing the first evidence of event-related potentials (ERPs) associated with time-based PM, and at examining differences and commonalities in the ERPs related to Strategic Monitoring mechanisms between event- and time-based PM tasks

When does right functional hemispheric lateralization arise? Evidence from preterm infants

In recent years, magnetic resonance imaging (MRI) has allowed researchers to individuate an earlier morphological development of the right hemisphere compared to the left hemisphere before birth. Anatomical asymmetry, however, does not necessarily mean functional asymmetry and whether the anatomical differences between hemispheres at this early age are paralleled by functional specializations is still unknown. Here we show electrophysiological evidence of an early functional right lateralization for pitch processing arising by 30 gestational weeks, not before, in preterm newborns

Neuropsychological evaluation of neurologically asymptomatic HIV-infected children

Forty-two children born to HIV positive mothers (29 infected at different stages of the disease, according to the Disease Control Classification Centers, and 13 noninfected) underwent evaluation using a battery of neuropsychological tests. Executive function impairments were present in all infected children, whereas memory and visuo-prassic deficits were evident only in those with full-blown AIDS. Language abilities and overall intelligence were spared. Performance of seroreverters was in the normal range. These findings suggest that even in neurologically asymptomatic children, neuropsychological evaluation can identify early impairment of specific cognitive functions. The findings are discussed in the light of the prognostic power of neuropsychological assessment for early signs of HIV neurological involvement

Prognostic role of spectral analysis of the EEG in premature infants

Brain maturation at early stages may be assessed by changes in spectral power frequencies of electroencephalogram (EEG) (Scher et al., 1997), but their predictive value for later outcome remains poorly understood. The aim of this study is to correlate neonatal spectral power values with developmental scores obtained at one year in infants born premature. EEG was recorded on twenty infants (23–34 weeks) at 35 post-conceptional weeks. In order to minimize handling, one bipolar channel (C3-C4) was recorded. Data were transformed into frequency domain using a Fast Fourier Transformation algorithm and divided in delta (0.5–4 Hz), theta (4–8 Hz), alpha (8–13 Hz) and beta (13–30 Hz) bands. As infants attained 12 months corrected age they underwent the Griffiths Mental Development Scales. Relative spectral power values recorded in the neonatal period were correlated with developmental scores. Relational skills and personal self autonomies sub-scale score correlated negatively with delta (r = −.60, p = .01) and positively with beta (r = .64, p = .007) and alpha (r = .63, p = .006) power values. Data on minor impairments in premature infants indicate a great incidence of psychiatric disorders later in life (Bhutta et al., 2002); the association of neonatal spectral power values with Griffith’s scores suggests a possible prognostic role of EEG spectral analysis in neonates born prematurely