Depressive Symptomatology and Priming Effects Among Younger and Older Adults.

Background/Study Context: This study examined the potential impact of self-reported depressive symptoms on the age-related capacity for inhibition and suppression, utilizing a negative priming paradigm. METHODS: One hundred eighty-five community-residing adults varying in age (98 younger adults, Mage = 22; 87 older adults, Mage = 69) completed a nonconscious priming task, the Geriatric Depression Scale (GDS), the White Bear Suppression Inventory (WBSI), the Depression Sensitivity Scale (DSS), a free thought suppression task, as well as several measures indexing overall cognitive ability and psychomotor speed. Hierarchical regressions investigated the interaction of depressive symptoms with age and its effect on both positive and negative priming performance, indexing both facilitation and inhibition effects, respectively. RESULTS: Results support the hypothesis that noncognitive factors affect effortful performance among older adults, although this influence varied with the specific component of the GDS, i.e., Dysphoria, Social Withdrawal, and Cognitive Control, and with the measure of depressive symptoms, i.e., GDS versus DSS. CONCLUSION: These data suggest that aging's impact on both facilitation and inhibition, e.g., positive and negative priming, are to an extent, a function of individual differences in depressive symptoms that interact with age in influencing the necessity to reallocate one's cognitive resources to deal with depressive thoughts and feelings.

Clinical practice as natural laboratory for psychotherapy research: a guide to case-based time-series analysis.

Both researchers and practitioners need to know more about how laboratory treatment protocols translate to real-world practice settings and how clinical innovations can be systematically tested and communicated to a skeptical scientific community. The single-case time-series study is well suited to opening a productive discourse between practice and laboratory. The appeal of case-based time-series studies, with multiple observations both before and after treatment, is that they enrich our design palette by providing the discipline another way to expand its empirical reach to practice settings and its subject matter to the contingencies of individual change. This article is a user's guide to conducting empirically respectable case-based time-series studies in a clinical practice or laboratory setting.

Evidence for an activation locus of the word-frequency effect in lexical decision.

The authors report a lexical decision experiment designed to determine whether activation is the locus of the word-frequency effect. K. R. Paap and L. S. Johansen (1994) reported that word frequency did not affect lexical decisions when exposure durations were brief; they accounted for this by proposing that data-limited conditions prevented late-occurring verification processes. Subsequently, P. A. Allen, A. F. Smith, M. Lien, T. A. Weber, and D. J. Madden (1997) and K. R. Paap, L. S. Johansen, E. Chun, and P. Vonnahme (2000) reported additional evidence that word-frequency effects do and do not have an activation locus, respectively. The authors further tested this issue in a lexical decision experiment using data-limited procedures--predicted by verification models to eliminate word-frequency effects. The authors observed word-frequency effects using individually determined exposure durations that were only 1 screen cycle longer than the exposure duration that yielded chance performance. Word-frequency effects persisted even when an adjusted measure of performance was used.

Redundancy gain and coactivation in bimodal detection: evidence for the preservation of coactive processing in older adults.

Previous investigations of adult age differences in the redundant signals effect suggest that both older and younger adults benefit from the presentation of redundant information. However, age deficits in divided attention may cause older adults to process redundant information in a different manner. In the present experiment, we tested between two competing explanations for the redundant signals effect: separate activation and coactivation. To investigate this issue, we used a bimodal detection task in which the auditory signal was a 1000-Hz tone and the visual signal was an asterisk. Both age groups showed significant violations of Miller's race model inequality, providing evidence for coactivation. These results suggest that, despite age-related deficits in divided attention, the ability to coactivate information from bimodal signals is spared with increased age.

Age differences in central (semantic) and peripheral processing: the importance of considering both response times and errors.

In this project we examined the effect of adult age on visual word recognition by using combined reaction time (RT) and accuracy methods based on the Hick-Hyman law. This was necessary because separate Brinley analyses of RT and errors resulted in contradicting results. We report the results of a lexical decision task experiment (with 96 younger adults and 97 older adults). We transformed the error data into entropy and then predicted RT by using entropy values separately for exposure duration (thought to influence peripheral processes) and word frequency (thought to influence central processes). For exposure duration, the entropy-RT functions indicate that older adults show higher intercepts and slopes than do younger adults, suggesting an encoding decrement for older adults. However, for word frequency, older adults show higher intercepts but not steeper slopes than younger adults. Older adults thus show a peripheral processing decrement but not a central processing decrement for lexical decision.

Age differences in overlapping-task performance: evidence for efficient parallel processing in older adults.

Two psychological refractory period (PRP) experiments were conducted to examine overlapping processing in younger and older adults. A shape discrimination task (triangle or rectangle) for Task 1 (T1) and a lexical-decision task (word or nonword) for Task 2 (T2) were used. PRP effects, response time for T2 increasing as stimulus onset synchrony (SOA) decreased, were obtained for both age groups. The effect of word frequency on T2 was smaller at the short SOA than at the long SOA, reflecting slack effects, which were larger for older than younger adults in both experiments. These results suggest that older adults can perform lexical access of T2 in parallel with the processing of T1 at least as efficiently as younger adults.