What causes the effect of age of acquisition in lexical processing?

Three hypotheses for effects of age of acquisition (AoA) in lexical processing are compared: the cumulative frequency hypothesis (frequency and AoA both influence the number of encounters with a word, which influences processing speed), the semantic hypothesis (early-acquired words are processed faster because they are more central in the semantic network), and the neural network model (early-acquired words are faster because they are acquired when a network has maximum plasticity). In a regression study of lexical decision (LD) and semantic categorization (SC) in Italian and Dutch, contrary to the cumulative frequency hypothesis, AoA coefficients were larger than frequency coefficients, and, contrary to the semantic hypothesis, the effect of AoA was not larger in SC than in LD. The neural network model was supported.     

Since when or how often? Dissociating the roles of age of acquisition (AoA) and lexical frequency in early visual word processing

The aim of the study was to investigate the effect of both word age of acquisition (AoA) and frequency of occurrence on the timing and topographical distribution of ERP components. The processing of early- versus late-acquired words was compared with that of high-frequency versus low-frequency words. Participants were asked to perform an orthographic task while EEG was recorded from 128 sites. RTs showed an effect of both word AoA and lexical frequency. ERPs revealed a neuro-functional dissociation between AoA and frequency effects in early word processing. AoA modulated the amplitude of left occipito-temporal selection-negativity, suggesting an effect of AoA on early orthographic and lexical access and revealing the crucial role of AoA in determining how words are neurally represented in the ventral pathway. Lexical frequency modulated the amplitude of left anterior negativity, providing evidence for the involvement of the left inferior frontal cortex in the processing of low-frequency words.     

What is the role of affect in the spacing effect?

In Experiments 1 and 2, after studying a list containing connotatively neutral words that were presented once or were presented at various spacing intervals, subjects either attempted free recall or made affective judgments of the study-list targets along a pleasant/unpleasant dimension. Spacing effects occurred in recall, and massed items were judged to be more unpleasantthan once-presented and spaced words. In the third experiment, subjects studied homogeneous lists composed of either connotatively good words or connotativelybad ones. Spacing effects were absent in the recall of both types of words because massed-practice words were recalled at a high level, one that was about the same as that for spaced-practice words. Affective judgments were unrelated to presentation condition, and both good and bad massed words were judged to be positive in affect. Although the data suggest that different study conditions can lead to different affective reactions, the results are moot with regard to the relationship between affect and the magnitude of spacing effects.     

Do attentional capacities and processing speed mediate the effect of age on executive functioning?

The executive processes are well known to decline with age, and similar data also exists for attentional capacities and processing speed. Therefore, we investigated whether these two last nonexecutive variables would mediate the effect of age on executive functions (inhibition, shifting, updating, and dual-task coordination). We administered a large battery of executive, attentional and processing speed tasks to 104 young and 71 older people, and we performed mediation analyses with variables showing a significant age effect. All executive and processing speed measures showed age-related effects while only the visual scanning task performance (selective attention) was explained by age when controlled for gender and educational level. Regarding mediation analyses, visual scanning partially mediated the age effect on updating while processing speed partially mediated the age effect on shifting, updating and dual-task coordination. In a more exploratory way, inhibition was also found to partially mediate the effect of age on the three other executive functions. Attention did not greatly influence executive functioning in aging while, in agreement with the literature, processing speed seems to be a major mediator of the age effect on these processes. Interestingly, the global pattern of results seems also to indicate an influence of inhibition but further studies are needed to confirm the role of that variable as a mediator and its relative importance by comparison with processing speed.     

Generation enhances semantic processing? The role of distinctiveness in the generation effect

The goal of the present study was to investigate the locus of the memory advantage for words that are generated according to a nonsemantic rule (letter transposition) over words that are presented intact (read words). In the first two experiments, a category instance generation task was used to test the possibility that the semantic features of generated words are more readily available than those of read words. This possibility was not supported. In Experiment 3, generation effects were found to depend on the level of meaningfulness of words in recall, but not in recognition. In Experiment 4, a between-list design eliminated the generation effect found in recall, but did not affect the generation effect in recognition. Taken together, these findings suggest that generating a target according to a letter transposition rule enhances the distinctiveness of the word along a nonsemantic dimension.     

Does interword spacing influence lexical processing in Chinese reading?

This study investigated how inserting spaces between Chinese words affected word recognition in Chinese reading. Eye movements of Chinese readers were recorded in a sentence reading task where high- and low-frequency target words were presented in both the spaced and normally unspaced texts. We found that fixation durations on target words were shorter in the high- than low-frequency conditions, and shorter in the spaced than unspaced conditions. The survival analysis revealed that interword spacing advanced the temporal onset of word frequency effects relative to the normally unspaced condition. However, inconsistent with the findings in English reading, there was no interaction between word frequency and interword spacing on all fixation duration measures, and the Bayes factor analyses also favoured the hypothesis of null interaction. These data suggest that interword spacing facilitates visual rather than lexical processing in Chinese reading, and thus improves our understanding on the roles of interword spacing across different writing systems.     

Order of acquisition in learning perceptual categories: A laboratory analogue of the age-of-acquisition effect?

In the age-of-acquisition (AoA) effect, an advantage for recognition and production is found for items learned early in life, as compared with items learned later. In this laboratory analogue, participants learned to categorize novel random checkerboard stimuli. Some stimuli were presented from the onset of training; others were introduced later. At test, when early and late stimuli had equal cumulative frequency, early stimuli were classified significantly more quickly. Because stimuli were randomly assigned to be introduced either early or late, we can conclude that early stimuli were categorized more quickly because of their order of acquisition. This finding suggests that age- or order-of-acquisition effects are a general property of any learning system.     

Reading in Spanish and Italian: Effects of age of acquisition in transparent orthographies?

Despite the similar transparency of their orthographies, reading in Italian has been found to be affected by frequency but not age of acquisition (AoA) [Barca, L., Burani, C., & Arduino, L. S. (2002). Word naming times and psycholinguistic norms for Italian nouns. Behaviour Research Methods, Instruments and Computers, 34, 424–434] while reading in Spanish is affected by AoA but not frequency [Cuetos, F., & Barbón, A. (2006). Word naming in Spanish. European Journal of Cognitive Psychology, 18, 415–436]. We examined this cross-linguistic difference, firstly, through a reanalysis of the Italian and Spanish reading latencies. After eliminating several between-experiment differences, we replicated the AoA effect in Spanish but not in Italian and the frequency effect in Italian but not in Spanish. The cross-linguistic comparison could not equate stimulus imageability; therefore, secondly, we compared the Italian reading latencies with new Spanish reading latencies for imageability-matched words. We found frequency effects but neither an AoA effect nor a language by AoA interaction. We argue that the previously reported cross-linguistic difference in the AoA effect resulted from a between-study difference in stimulus imageability. More imageable words induced more semantic involvement in reading, yielding an AoA effect in Spanish.     

What causes scale errors in children?

A recent article by DeLoache et al. has documented an intriguing phenomenon in the development of action planning in young children. When children act on toy replicas of larger objects they make scale errors that are consistent with the full-sized object. Although the actions selected are inappropriate, their execution accurately takes into account the true size of the target. This phenomenon permits tests of the predictions of the perception-action and planning-control models of vision for action.     

What kind of attention modulates the Stroop effect?

An intersection of three literatures (skilled word recognition, spatial attention, and the Stroop effect) is addressed in a series of four experiments. The results, in conjunction with other observations, are taken to suggest that (1) thedefault value for spatial attention in visual word recognition is distributed across the word, (2) precuing a single letter position serves to narrow the focus of spatial attention, and (3) this reduces or prevents activation in the word recognition system. Consequently, the Stroop effect is reduced in magnitude or eliminated, depending on details of the context. Contrary to the widespread view that it reflects automatic processing, the Stroop effect is better conceptualized as reflecting the action of default settings in the word recognition and attentional systems. Some relations between consciousness, context, and control are noted.     

Lexical decision in children: sublexical processing or lexical search?

Length effects in the lexical decision latencies of children might indicate that children rely on sublexical processing and essentially approach the task as a naming task. We examined this possibility by means of the effects of neighbourhood size and articulatory suppression on lexical decision performance. Sixty-six beginning and 62 advanced readers performed a lexical decision task in a standard, articulatory suppression, or tapping condition. We found length effects on words and nonwords in the children's lexical decisions. However, the effects of neighbourhood size were similar to those reported for adult lexical decisions, rather than the effects previously found in children's naming. In addition, no effect was found of articulatory suppression. Both findings suggest that, despite clear length effects, children do not adopt a naming task approach but, like adults, base lexical decisions mainly on a lexical search. These results pose a challenge for several computational models of reading.     

What underlies the deficit in reported recollective experience in old age?

In recognition memory, older adults report fewer occasions on which recognition is accompanied by recollection of the original encoding context. This study asks why this occurs. Two main hypotheses were tested: (1) Older adults fail to encode the items sufficiently when first they experience them. (2) Older adults have a retrieval deficit that prevents efficient reintegration of target and context. In addition, the hypothesis that frontal lobe integrity is essential for recollective experience was examined. Twenty older (mean age 70.7 years) and 20 younger (mean age 22.9 years) adults were asked to study a list of items and to verbalize the strategies they were using to remember. A further 20 older adults (mean age 70.0 years) were tested without the think-aloud protocol. Subsequently, subjects completed a battery of psychometric tests before completing a recognition test. As expected, older adults showed less recollective experience. They differed from the young in how they encoded the material, and once this difference was accounted for, no age differences in recollective experience remained. There was little evidence to support the hypothesis that frontal lobe integrity plays a role in the reduction of recollective experience with age.     

What has caused the Flynn effect? Secular increases in the Development Quotients of infants

Results of five studies show that during the second half of the twentieth century there were increases in the Development Quotients (DQs) of infants in the first two years of life. These gains were obtained for the Bayley Scales in the United States and Australia, and for the Griffiths Test in Britain. The average of 19 data points is a DQ gain of approximately 3.7 DQ points per decade. Similar gains of approximately 3.9 IQ points per decade have been present among preschool children aged 4–6 years. These gains are about the same as the IQ gains of school age students and adults on the Wechsler and Binet tests. This suggests that the same factor has been responsible for all these secular gains. This rules out improvements in education, greater test sophistication, etc. and most of the other factors that have been proposed to explain the Flynn effect. It is proposed that the most probable factor has been improvements in pre-natal and early post-natal nutrition.     

What aspects of face processing are impaired in developmental prosopagnosia?

Developmental prosopagnosia (DP) is a severe impairment in identifying faces that is present from early in life and that occurs despite no apparent brain damage and intact visual and intellectual function. Here, we investigated what aspects of face processing are impaired/spared in developmental prosopagnosia by examining a relatively large group of individuals with DP (n = 8) using an extensive battery of well-established tasks. The tasks included measures of sensitivity to global motion and to global form, detection that a stimulus is a face, determination of its sex, holistic face processing, processing of face identity based on features, contour, and the spacing of features, and judgments of attractiveness. The DP cases showed normal sensitivity to global motion and global form and performed normally on our tests of face detection and holistic processing. On the other tasks, many DP cases were impaired but there was no systematic pattern. At least half showed deficits in processing of facial identity based on either the outer contour or spacing of the internal features, and/or on judgments of attractiveness. Three of the eight were impaired in processing facial identify based on the shape of internal features. The results show that DP is a heterogeneous condition and that impairment in recognizing faces cannot be predicted by poor performance on any one measure of face processing.     

Do the effects of subjective frequency and age of acquisition survive better word frequency norms?

Megastudies with processing efficiency measures for thousands of words allow researchers to assess the quality of the word features they are using. In this article, we analyse reading aloud and lexical decision reaction times and accuracy rates for 2,336 words to assess the influence of subjective frequency and age of acquisition on performance. Specifically, we compare newly presented word frequency measures with the existing frequency norms of Ku?era and Francis (1967) Ku?era, H. and Francis, W. 1967. Computational analysis of present-day American English, Providence, RI: Brown University Press.  [Google Scholar], HAL (Burgess & Livesay, 1998 Burgess, C. and Livesay, K. 1998. The effect of corpus size in predicting reaction time in a basic word recognition task: Moving on from Kucera and Francis. Behavior Research Methods, Instruments, & Computers, 30: 272–277. [Crossref] , [Google Scholar]), Brysbaert and New (2009) Brysbaert, M. and New, B. 2009. Moving beyond Kucera and Francis: A critical evaluation of current word frequency norms and the introduction of a new and improved word frequency measure for American English. Behavior Research Methods, 41: 977–990. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar], and Zeno, Ivens, Millard, and Duvvuri (1995) Zeno, S. M., Ivens, S. H., Millard, R. T. and Duvvuri, R. 1995. The educator's word frequency guide, Brewster, NY: Touchstone Applied Science.  [Google Scholar]. We show that the use of the Ku?era and Francis word frequency measure accounts for much less variance than the other word frequencies, which leaves more variance to be “explained” by familiarity ratings and age-of-acquisition ratings. We argue that subjective frequency ratings are no longer needed if researchers have good objective word frequency counts. The effect of age of acquisition remains significant and has an effect size that is of practical relevance, although it is substantially smaller than that of the first phoneme in naming and the objective word frequency in lexical decision. Thus, our results suggest that models of word processing need to utilize these recently developed frequency estimates during training or setting baseline activation levels in the lexicon.     

Analysis of group differences in processing speed: Where are the models of processing?

Recently, Myerson, Adams, Hale, and Jenkins (2003) replied to arguments advanced by Ratcliff, Spieler, and McKoon (2000) about interpretations of Brinley functions. Myerson et al. (2003) focused on methodological and terminological issues, arguing that (1) Brinley functions are not quantile-quantile (QQ) plots of distributions of mean reaction times (RTs) across conditions; that the fact that the slope of a Brinley function is the ratio of the standard deviations of the two distributions of means has no implications for the use of slope as a measure of processing speed; that the ratio of slopes of RT functions for older and young subjects plotted against independent variables equals the Brinley function slope; and that speed-accuracy criterion effects do not account for slowing with age. We reply by showing that Brinley functions are plots of quantiles against quantiles; that the slope is best estimated by the ratio of standard deviations because there is variability in the distributions of mean RTs for both older and young subjects; that the interpretation of equality of the slopes Brinley functions and plots of RTs against independent variables in terms of processing speed is model dependent; and that speed-accuracy effects in some, but not all, experiments are solely responsible for Brinley slopes greater than 1. We conclude by reiterating the point that was not addressed in Myerson et al. (2003), that the goal of research should be modelbased accounts of processing that deal with correct and error RT distributions and accuracy.     

What aspects of vision facilitate haptic processing?

We investigate how vision affects haptic performance when task-relevant visual cues are reduced or excluded. The task was to remember the spatial location of six landmarks that were explored by touch in a tactile map. Here, we use specially designed spectacles that simulate residual peripheral vision, tunnel vision, diffuse light perception, and total blindness. Results for target locations differed, suggesting additional effects from adjacent touch cues. These are discussed. Touch with full vision was most accurate, as expected. Peripheral and tunnel vision, which reduce visuo-spatial cues, differed in error pattern. Both were less accurate than full vision, and significantly more accurate than touch with diffuse light perception, and touch alone. The important finding was that touch with diffuse light perception, which excludes spatial cues, did not differ from touch without vision in performance accuracy, nor in location error pattern. The contrast between spatially relevant versus spatially irrelevant vision provides new, rather decisive, evidence against the hypothesis that vision affects haptic processing even if it does not add task-relevant information. The results support optimal integration theories, and suggest that spatial and non-spatial aspects of vision need explicit distinction in bimodal studies and theories of spatial integration.