The Effects of Frequency and Predictability on Eye Fixations in Reading: Implications for the E-Z Reader Model.

Readers read sentences containing target words varying in frequency and predictability. The observed pattern of data for fixation durations only mildly departed from additivity, with predictability effects that were slightly larger for low-frequency than for high-frequency words. The pattern of data for skipping was different as predictability affected only the probability of skipping for high-frequency target words. Simulations of these data using the E-Z Reader model indicated that a single-process model was unlikely to provide a good fit for both measures. A version of the model that assumes that (a) word-encoding time is additively affected by frequency and predictability and (b) difficulty with postlexical processing of the target word causes a double take accounted for the data while indicating that the relationship between the duration of hypothesized word-encoding stages and observed fixation durations is not likely to be transparent. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional processes in time perception: Effects of mental workload and event structure.

The role of attention in timing was evaluated in 2 experiments. In Experiment 1, participants reproduced the durations of melodies with either a coherent or an incoherent structure. Participants were tested under control (timing only) and detection (timing plus target detection) workload conditions. Reproductions were shorter and more inaccurate under detection conditions, and incoherent event structure extended the effect to a wider range of durations. In Experiment 2, participants reproduced the durations of auditory prose passages that represented 3 levels of mental workload and 3 levels of event structure. Both increases in workload and the degradation of structure led to inaccurate reproductions. The results point to the central role of attention in temporal experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inter- and Intraindividual Variability in Recognition Memory: Effects of Aging and Estrogen Use.

Traditionally, studies of cognitive aging have focused on comparing the average performance of younger and older adults, whereas variability around the mean has been attributed to task-irrelevant noise. The present study examined the hypothesis that variability in memory performance increases with age and that estrogen helps temper age-related increases in variability. Postmenopausal estrogen users, estrogen and progestin (est + prog) users, and nonusers, as well as younger women, completed 16 blocks of an item-source memory task. Older women showed greater variability than younger women on measures of dispersion and consistency. Estrogen users, but not est + prog users, performed more consistently than nonusers. Overall, age-related increases in variability differed with the type of variability measured, and estrogen use, but not est + prog use, appeared to reduce age-related increases in at least 1 form of variability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reinforcing and Subjective Effects of Methylphenidate: Dose and Time in Bed.

So that reinforcing and subjective effects of methylphenidate as a function of dose and level of sleepiness could be evaluated, 21 volunteers received methylphenidate (5, 10, or 20 mg) or placebo on 2 sampling days. After 4 and 8 hr time in bed (TIB), they chose their preferred capsule on 5 days. Methylphenidate was chosen more frequently after 4 hr TIB (60%) than it was after 8 hr TIB (33%). The strongest preference (68%) was seen in the 10-mg group. At 10 and 20 mg, stimulant-like subjective effects were reported. The 10-mg group was more adversely affected by the restricted bedtime and showed more pronounced drug effects with methylphenidate. These results indicate that sleepiness modulates the reinforcing and subjective effects of methylphenidate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reconstructive Memory Related to Adolescent-Parent Conflict Interactions: The Influence of Attachment-Related Representations on Immediate Perceptions and Changes in Perceptions Over Time.

This investigation examined the hypothesis that individuals change, over time, their perceptions of interactions with attachment figures in ways that are consistent with their attachment-related representations of those individuals. In an original and a replication study, adolescents participated in laboratory conflict discussions with each of their parents. Adolescents rated their perceptions of the interactions immediately after the conflict discussions, then again 6 weeks later. Results indicated that (a) adolescents' immediate perceptions of the interactions were influenced by their attachment-related representations of their parents, and (b) adolescents' perceptions, over a period of 6 weeks, shifted such that their later perceptions were more congruent with their attachment-related representations than were their immediate perceptions. Implications for the continuity of relational models and relationship patterns are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification of Tone Duration, Line Length, and Letter Position: An Experimental Approach to Timing and Working Memory Deficits in Schizophrenia.

Patients with schizophrenia display numerous cognitive deficits, including problems in working memory, time estimation, and absolute identification of stimuli. Research in these fields has traditionally been conducted independently. We examined these cognitive processes using tasks that are structurally similar and that yield rich error data. Relative to healthy control participants (n = 20), patients with schizophrenia (n = 20) were impaired on a duration identification task and a probed-recall memory task but not on a line-length identification task. These findings do not support the notion of a global impairment in absolute identification in schizophrenia. However, the authors suggest that some aspect of temporal information processing is indeed disturbed in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Divided Attention in Younger and Older Adults: Effects of Strategy and Relatedness on Memory Performance and Secondary Task Costs.

Divided attention at encoding leads to a significant decline in memory performance, whereas divided attention during retrieval has relatively little effect; nevertheless, retrieval carries significant secondary task costs, especially for older adults. The authors further investigated the effects of divided attention in younger and older adults by using a cued-recall task and by measuring retrieval accuracy, retrieval latency, and the temporal distribution of attentional costs at encoding and retrieval. An age-related memory deficit was reduced by pair relatedness, whereas strategy instructions benefited both age groups equally. Attentional costs were greater for retrieval than for encoding, especially for older adults. These findings are interpreted in light of notions of an age-related associative deficit (M. Naveh-Benjamin, 2000) and age-related differences in the use of self-initiated activities and environmental support (F. I. M. Craik, 1983, 1986). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Estimating Age Change in List Recall in Asset and Health Dynamics of the Oldest-Old: The Effects of Attrition Bias and Missing Data Treatment.

Average change in list recall was evaluated as a function of missing data treatment (Study 1) and dropout status (Study 2) over ages 70 to 105 in Asset and Health Dynamics of the Oldest-Old data. In Study 1 the authors compared results of full-information maximum likelihood (FIML) and the multiple imputation (MI) missing-data treatments with and without independent predictors of missingness. Results showed declines in all treatments, but declines were larger for FIML and MI treatments when predictors were included in the treatment of missing data, indicating that attrition bias was reduced. In Study 2, models that included dropout status had better fits and reduced random variance compared with models without dropout status. The authors conclude that change estimates are most accurate when independent predictors of missingness are included in the treatment of missing data with either MI or FIML and when dropout effects are modeled. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of Apolipoprotein E Genotype on Spatial Attention, Working Memory, and Their Interaction in Healthy, Middle-Aged Adults: Results From the National Institute of Mental Health's BIOCARD Study.

The cognitive consequences of the apolipoprotein E-ε4 (APOE-ε4) allele were examined in middle age, before likely onset of symptoms of Alzheimer's disease. The authors identified 3 cognitive processes--visuospatial attention, spatial working memory, and the effect of visuospatial attention on working memory--and devised "behavioral assays" of the integrity of components of these processes. Redirecting visuospatial attention, retention of memory for location, and attentional modulation of memory of target location were affected by APOE genotype. Visuospatial attention showed additive effects of ε4 gene dose; each additional ε4 allele inherited further slowed disengagement from invalidly cued space. In contrast, working memory performance was affected only in ε4 homozygotes. Effect sizes for the APOE gene were moderate to large, ranging from 14% to 24%. Effects of APOE genotype on component processes of cognition in healthy, middle-aged adults is consistent with the emergence in adulthood of an APOE-ε4 cognitive phenotype. (PsycINFO Database Record (c) 2010 APA, all rights reserved)