Differential Age Effects on Semantic and Syntactic Priming

Temporally and spatially distinct theta oscillations dissociate a language-specific from a domain-general processing mechanism across the age trajectory

The cognitive functionality of neural oscillations is still highly debated, as different functions have been associated with identical frequency ranges. Theta band oscillations, for instance, were proposed to underlie both language comprehension and domain-general cognitive abilities. Here we show that the ageing brain can provide an answer to the open question whether it is one and the same theta oscillation underlying those functions, thereby resolving a long-standing paradox. While better cognitive functioning is predicted by low theta power in the brain at rest, resting state (RS) theta power declines with age, but sentence comprehension deteriorates in old age. We resolve this paradox showing that sentence comprehension declines due to changes in RS theta power within domain-general brain networks known to support successful sentence comprehension, while low RS theta power within the left-hemispheric dorso-frontal language network predicts intact sentence comprehension. The two RS theta networks were also found to functionally decouple relative to their independent internal coupling. Thus, both temporally and spatially distinct RS theta oscillations dissociate a language-specific from a domain-general processing mechanism.

The representation of ontological category concepts as affected by healthy aging: normative data and theoretical implications

Attributes associated with concept representations, such as familiarity, typicality, and age of acquisition, have been shown to be important influences on lexical-semantic processing. In most previous studies of healthy and pathological aging, these attributes are not equated for younger and older adults separately on the stimuli used. In this study, normative data were collected to test whether there exist any age differences in these attributes. The results demonstrate that the ratings given by younger and older adults on natural and manmade category items correlated positively. However, age differences were also apparent, whereby older adults provided higher ratings overall than younger adults. Suggestions and hypotheses are presented to explain this pattern of age differences, which relate to how category concepts may be represented by healthy younger and older adults. Also, the possible implications for these differential age ratings on lexical-semantic processing are discussed. The age differences apparent in this study demonstrate the need to consider age-appropriate normative ratings in the selection of stimuli for use in lexical-semantic processing studies of aging, and the normative data presented provide a means of equating category stimuli. The complete list of all the means is available at www.psychonomic.org/archive.

The costs and benefits of tonal centers for chord processing

Harmonic priming studies have shown that a musical context, with its established tonal center, influences target chord processing. This study investigated costs and benefits of priming tonal centers for target processing by adding a baseline condition (sequences without a specific tonal center). Results confirmed harmonic priming, with faster processing for related than for unrelated and less related targets (tonic chord, out-of-key chord, subdominant chord). Comparing targets in baseline contexts with targets in sequences with well-established tonal centers revealed a benefit of processing for related targets but a cost of processing for unrelated and less related targets. Findings are discussed in terns of tonal knowledge activation and suggest that an activated tonal center gives rise to strong expectations for the tonic.

The adaptiveness of selection, optimization, and compensation as strategies of life management: evidence from a preference study on proverbs

Proverbs were used to examine whether laypeople's conceptions of or preferences for life-management strategies are consistent with the model of selection, optimization, and compensation (SOC model). The SOC model posits that there are three fundamental processes of life management: selection, optimization, and compensation. In two studies (N = 64; N = 131), young (19-32 years) and older adults (59-85 years) were asked to match proverbs to sentence stems indicative of life-management situations. Of the proverbs, half reflected one component of SOC and half alternative, non-SOC life-management strategies. SOC-related and alternative proverbs were matched on familiarity, understandability, and meaningfulness. Two main results were obtained: Young and older adults chose proverbs reflecting SOC (a) more frequently and (b) faster than alternative proverbs. Study 3 (N = 60, 19-32 year-old participants) ruled out that these results were due to an artifact resulting from a stronger, purely semantic relationship of the specific sentence stems with the SOC-related proverbs. Studies 4 (N = 48 younger and older adults) and 5 (N = 20 younger adults) were conducted to test discriminant validity. In contrast with tasks involving long-term goal orientation and success, there were no preferences for SOC-related proverbs for life contexts involving relaxation or leisure. Taken together, results of these studies indicate that individuals, when asked to choose between alternative proverbs characterizing ways of managing life, prefer SOC-related proverbs.