Letter Position Coding with Fred Astaire: Inversion of Letter Position Substitution Effects in Reverse Spelled Words.

The effects of letter substitutions have been linked to their position within a word (letter position effects). The current study expanded upon previous research by examining letter-position effects for letter substitutions using forward- and reverse-spelled word primes. Often substituting a letter on one side of a word will have a stronger impact on performance than substituting a letter on the other side of a word. In three experiments it was revealed that the letter-position effects of substitutions changed places when words were spelled backwards. This occurred when both the target and prime were spelled backwards. This was evidence of a congruency effect of letter-position priming. The ramifications of these results for word recognition and transfer are discussed. However, the need for future research should focus on the possibility of an inversion process/mechanism.

Word Frequency Effects for LEET Lettering in Word Recognition.

Letter substitution has been shown to have a cost to word recognition performance, such as increased reaction time. The use of orthographically similar numbers or symbols as a substitute for letters is known as LEET. Perea, Duñabeitia, and Carreiras (2008) showed that word recognition was not affected when LEET substitutions were used as primes. This study examined whether the effects of LEET prime substitutions would remain constant across word frequency. The apparent lack of substitution costs may have been an effect of word-level processing such as holistic bias for high-frequency words. Evidence that LEET does not have an appreciable cost to performance across word frequency suggests that such orthographic substitutions are processed much like normally lettered words, which supported Perea et al.'s findings. It was suggested that LEET substitutions offset substitution costs because of orthography (because of more complete processing of nonsubstituted letters) rather than lexical effects (i.e., holistic bias).

Effects of targets embedded within words in a visual search task.

Visual search performance can be negatively affected when both targets and distracters share a dimension relevant to the task. This study examined if visual search performance would be influenced by distracters that affect a dimension irrelevant from the task. In Experiment 1 within the letter string of a letter search task, target letters were embedded within a word. Experiment 2 compared targets embedded in words to targets embedded in nonwords. Experiment 3 compared targets embedded in words to a condition in which a word was present in a letter string, but the target letter, although in the letter string, was not embedded within the word. The results showed that visual search performance was negatively affected when a target appeared within a high frequency word. These results suggest that the interaction and effectiveness of distracters is not merely dependent upon common features of the target and distracters, but can be affected by word frequency (a dimension not related to the task demands).

Age-related sparing of parafoveal lexical processing.

UNLABELLED: BACKGROUND/STUDY CONTEXT: This study examined the role of increased adult age in the processing of lexical information presented in foveal and parafoveal areas of the retina (right and left visual fields). Previous research has shown that older adults are able to compensate for age-related changes though a highly practiced skill (Salthouse, 1984 , Journal of Experimental Psychology: General, 113, 345-371). The authors examined if older adults would show a lexical-only parafoveal benefit. METHODS: Two experiments were conducted on both younger and older adults. In Experiment 1, participants completed a lexical decision task that presented words in the fovea and parafovea in both visual fields. In Experiment 2, the task was a font discrimination task (nonlexical) with foveal and parafoveal presentation in both visual fields. RESULTS: In Experiment 1, the authors observed word frequency effects for both foveal and right parafoveal presentation locations. This effect was present for both older and younger adults. Experiment 2 was a font discrimination task and there was no right parafoveal advantage for older adults on this task, suggesting that this effect observed in Experiment 1 was lexical in nature due to the highly overlearned nature of word recognition. CONCLUSION: These results suggest that older adults may compensate for slower encoding time in reading by encoding text to the right of fixation more efficiently than younger adults. This suggests an asymmetrical change in the useful field of view that is lexical in nature.

Cross-task compatibility and age-related dual-task performance.

UNLABELLED: BACKGROUND/STUDY CONTEXT: This study examined the effects of stimulus-stimulus and response-response cross-task compatibility and aging on dual-task performance. Hypothesis 1 predicted that the response code compatibility effect in both experiments would benefit older adults comparably to younger adults. Hypothesis 2 predicted that stimulus-stimulus compatibility would be additive to the effects of cross-task compatibility. METHODS: Younger and older adults participated in two dual-task experiments. Experiment 1 utilized a cross-task compatibility design identical to that of Koch and Prinz ( 2002 , Journal of Experimental Psychology: Human Perception and Performance, 28, 192-201). Experiment 2 added a stimulus-stimulus compatibility condition. RESULTS: The results of both experiments supported Hypothesis 1. Older adults displayed comparable cross-task compatibility effects to younger adults. The data did not support Hypothesis 2. The response-response compatibility effect from Experiment 1 was replicated, but the effect of stimulus-stimulus compatibility was not significant. CONCLUSION: The results of both experiments showed that older adults were able to take advantage of cross-task compatibility as a task design to improve dual-task performance. The lack of stimulus-stimulus compatibility effects in Experiment 2 suggested that the benefit of task design may be limited in effect.

Influence of encoding difficulty, word frequency, and phonological regularity on age differences in word naming.

It is presently unclear as to why older adults take longer than younger adults to recognize visually presented words. To examine this issue in more detail, the authors conducted two word-naming studies (Experiment 1: 20 older adults and 20 younger adults; Experiment 2: 60 older adults and 60 younger adults) to determine the relative effects of orthographic encoding (case type), lexical access (word frequency), and phonological regularity (regular vs. irregular phonology). The hypothesis was that older adults attempt to compensate for sensory and motor slowing by using progressively larger perceptual units (holistic encoding). However, if forced to use smaller perceptual units (e.g., by using mixed-case presentation), it was predicted that older adults would be particularly challenged. Older adults did show larger case-mixing effects than younger adults (suggesting that older adults' performances were especially poor when they were forced to use smaller perceptual units), but there were no age differences in word frequency or phonological regularity even though both age groups showed main effects for these variables. These results suggest that lexical access skill remains stable in the addressed (orthographic/semantic) and assembled (phonological) routes over the life span, but that older adults slow down in recognizing words because it takes them longer to normalize (perceptually "clean up") noisier sensory information.

The early bird does not get the worm: time-of-day effects on college students' basic cognitive processing.

We conducted a neuropsychological and cognitive assessment study to determine whether time of day affects cognitive performance. We measured executive control (fluency), processing speed, semantic memory, and episodic memory performance. We followed 56 students across 3 different times of day, testing performance on vocabulary, fluency, processing speed, and episodic memory. Results showed an advantage for fluency and digit symbol task performance in the afternoon and evening testing times relative to morning testing (regardless of testing order), but that time of day did not affect semantic or episodic memory performance. These results suggest that optimal executive functioning and processing speed may occur for typical college students in the afternoon and evening regardless of time-of-day preference.

Visual word recognition without central attention: evidence for greater automaticity with greater reading ability.

The present study examined individual differences in the automaticity of visual word recognition. Specifically, we examined whether people can recognize words while central attention is devoted to another task and how this ability depends on reading skill. A lexical-decision Task 2 was combined with either an auditory or visual Task 1. Regardless of the Task 1 modality, Task 2 word recognition proceeded in parallel with Task 1 central operations for individuals with high Nelson-Denny reading scores, but not for individuals with low reading scores. We conclude that greater lexical skill leads to greater automaticity, allowing better readers to more efficiently perform lexical processes in parallel with other attention-demanding tasks.

Visual word recognition without central attention: evidence for greater automaticity with advancing age.

The present experiments examined the automaticity of word recognition. The authors examined whether people can recognize words while central attention is devoted to another task and how this ability changes across the life span. In Experiment 1, a lexical decision Task 2 was combined with either an auditory or a visual Task 1. Regardless of the Task 1 modality, Task 2 word recognition proceeded in parallel with Task 1 central operations for older adults but not for younger adults. This is a rare example of improved cognitive processing with advancing age. When Task 2 was nonlexical (Experiment 2), however, there was no evidence for greater parallel processing for older adults. Thus, the processing advantage appears to be restricted to lexical processes. The authors conclude that greater cumulative experience with lexical processing leads to greater automaticity, allowing older adults to more efficiently perform this stage in parallel with another task.

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.

An emotional mediation theory of differential age effects in episodic and semantic memories.

Although there is a large decrement in central episodic memory processes as adults age, there is no appreciable decrement in central semantic memory processes (Allen et al., Journal of Gerontology: Psychological Sciences, 57B, P173-P186, 2002; Allen et al., Experimental Aging Research, 28, 111-142, 2002; Mitchell, Journal of Experimental Psychology: Learning, Memory, and Cognition, 15, 31-49, 1989). The authors develop a theory of episodic memory's connections to cognitive, emotional, and motivational systems to explain these differential age effects. The theory is discussed within the context of the cognitive neuroscience research regarding limbic system connectivity in conjunction with Damasio's notion of somatic markers (Descartes' error: Emotion, reason, and the human brain, New York: Grosset/Putnam, 1994). The central hypothesis is that elements of limbic system circuitry, including portions of the medial temporal lobes and frontal cortex, are associated with both working and long-term episodic memory performance, and by extension, with the capacity to engage in emotion-guided, self-regulatory processes that depend heavily on episodic memory. In contrast, the semantic memory system may have less shared interface with episodic and affective networks (i.e., the limbic-related system), and therefore remain independent of neurocognitive changes impacting emotional states and episodic-type memory processes. Accordingly, this framework may account for the pattern of age-related declines in episodic relative to semantic memory, particularly if older adults experience less emotional activation, and therefore fewer somatic markers, than younger adults. An initial empirical examination of this emotional mediation theory is presented, using preexisting data that include indicators of age, chronic tendency to focus on negative emotional stimuli (neuroticism), and working memory performance.

Differential age effects for case and hue mixing in visual word recognition.

The authors compare older adults' lexical-decision data with younger adults' data reported in P. Allen, A. F. Smith, et al. (2002). On the basis of their work, it was proposed that consistent-case wordswould be processed by the faster holistic (magnodominated) stream, but that mixed-case words would be processed by the slower analytic (interblob-dominated or blob-dominated) steams. Hue mixing was predicted to have no effect on consistent-case performance, but mixed-hue/mixed-case words were predicted to be recognized faster than monochrome/mixed-case words. Younger adults showed the predicted results, but older adults did not. These results suggest that holistic central processes are maintained, but that older adults exhibited an analytic decrement