Semantic interference in a delayed naming task: Evidence for the response exclusion hypothesis.

In 2 experiments participants named pictures of common objects with superimposed distractor words. In one naming condition, the pictures and words were presented simultaneously on every trial, and participants produced the target response immediately. In the other naming condition, the presentation of the picture preceded the presentation of the distractor by 1,000 ms, and participants delayed production of their naming response until distractor word presentation. Within each naming condition, the distractor words were either semantic category coordinates of the target pictures or unrelated. Orthogonal to this manipulation of semantic relatedness, the frequency of the pictures' names was manipulated. The authors observed semantic interference effects in both the immediate and delayed naming conditions but a frequency effect only in the immediate naming condition. These data indicate that semantic interference can be observed when target picture naming latencies do not reflect the bottleneck at the level of lexical selection. In the context of other findings from the picture-word interference paradigm, the authors interpret these data as supporting the view that the semantic interference effect arises at a postlexical level of processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Failing to Get the Gist: Reduced False Recognition of Semantic Associates in Semantic Dementia.

In 2 experiments involving patients with semantic dementia, the authors investigated the impact of semantic memory loss on both true and false recognition. Experiment 1 involved recognition memory for categories of everyday objects that shared a predominantly semantic relationship. The patients showed preserved item-specific recollection for the pictorial stimuli but, compared with control participants, exhibited significantly reduced utilization of gist information regarding the categories of objects. The latter result is consistent with the patients' degraded semantic knowledge. Experiment 2 involved categories of abstract objects that were related to one another perceptually rather than semantically. Patients with semantic dementia obtained item-specific recollection and gist memory scores that were indistinguishable from those of control participants. These results suggest that the reduction in gist memory in semantic dementia is largely specific to semantic representations and cannot be attributed to general difficulty with abstracting and/or utilizing gistlike commonalities between stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implicit learning of semantic category sequences: Response-independent acquisition of abstract sequential regularities.

Through the use of a new serial naming task, the authors investigated implicit learning of repeating sequences of abstract semantic categories. Participants named objects (e.g., table, shirt) appearing in random order. Unbeknownst to them, the semantic categories of the objects (e.g., furniture, clothing) followed a repeating sequence. Irrespective of whether participants were instructed to attend to the categories (Experiment 1) or whether no mention was made of the categories (Experiments 2 and 3), naming latencies reliably increased when the repeating category sequence was switched to a random sequence. This was the case even for participants showing no explicit knowledge in reproduction and recognition tests. Results indicate that abstract sequential structures are learned implicitly, even if neither the surface stimuli nor the responses follow a sequence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Use of IQ-Adjusted Norms to Predict Progressive Cognitive Decline in Highly Intelligent Older Individuals.

Identifying high-functioning older individuals in preclinical phases of Alzheimer's disease (AD) may require more sensitive methods than the standard approach. The authors explored the utility of adjusting for premorbid intelligence to predict progressive cognitive decline or Mild Cognitive Impairment (MCI) in 42 highly intelligent older individuals. When scores were adjusted for baseline IQ, 9 participants had executive impairments, 11 had memory impairments, and 22 scored in the normal range. None were impaired according to standard age norms. Three and a half years later, 9 participants with IQ-adjusted memory impairment declined in naming, visuospatial functioning, and memory; 6 convened to MCI. Three participants with normal memory declined. Implications for using IQ-adjusted norms to predict preclinical AD are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

How many memory systems? Evidence from aging.

The present research tested Tulving's (1985) ternary memory theory. Young (ages 19–32) and older (ages 63–80) adults were given procedural, semantic, and episodic memory tasks. Repetition, lag, and codability were manipulated in a picture-naming task, followed by incidental memory tests. Relative to young adults, older adults exhibited lower levels of recall and recognition, but these episodic measures increased similarly as a function of lag and repetition in both age groups. No age-related deficits emerged in either semantic memory (vocabulary, latency slopes, naming errors and tip-of-the-tongue responses) or procedural memory (repetition priming magnitude and rate of decline). In addition to the age by memory task dissociations, the manipulation of codability produced slower naming latencies and more naming errors (semantic memory), yet promoted better recall and recognition (episodic memory). Finally, a factor analysis of 11 memory measures revealed three distinct factors, providing additional support for a tripartite memory model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The influence of apoe status on episodic and semantic memory: Data from a population-based study.

In a prospective cohort study, the authors demonstrated a more pronounced ε4-related deficit for participants 70 years of age and older in tasks assessing episodic recall. Apolipoprotein E (APOE) and age interacted for episodic memory tasks, whereas the interaction for semantic memory tasks was between APOE and test wave. Heterozygotes of ε4 between middle-age and young-old participants performed at a higher level than noncarriers of this allele in recall tasks. A dose effect was found such that carriers of 2 ε4 alleles failed more profoundly in acquiring and recollecting episodic information than carriers of 1 ε4 allele, who in turn failed more than carriers of non-ε4 alleles. The pattern of findings observed for older ε4 carriers suggests that these individuals have particular difficulty when the executive task demands are high. Several factors (e.g., smaller hippocampal volumes, less effective neural repair mechanisms) may account for these findings. On the basis of the data obtained, the authors argue that analyses of the effect of specific genes in cognition should be accompanied by assessment of performance at a specific level, with due attention to the individual's age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Are the memories of older adults positively biased?

There is disagreement in the literature about whether a "positivity effect" in memory performance exists in older adults. To assess the generalizability of the effect, the authors examined memory for autobiographical, picture, and word information in a group of younger (17-29 years old) and older (60-84 years old) adults. For the autobiographical memory task, the authors asked participants to produce 4 positive, 4 negative, and 4 neutral recent autobiographical memories and to recall these a week later. For the picture and word tasks, participants studied photos or words of different valences (positive, negative, neutral) and later remembered them on a free-recall test. The authors found significant correlations in memory performance, across task material, for recall of both positive and neutral valence autobiographical events, pictures, and words. When the authors examined accurate memories, they failed to find consistent evidence, across the different types of material, of a positivity effect in either age group. However, the false memory findings offer more consistent support for a positivity effect in older adults. During recall of all 3 types of material, older participants recalled more false positive than false negative memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The contribution of recollection and familiarity to recognition memory: A study of the effects of test format and aging.

Whether the format of a recognition memory task influences the contribution of recollection and familiarity to performance is a matter of debate. The authors investigated this issue by comparing the performance of 64 young (mean age = 21.7 years; mean education = 14.5 years) and 62 older participants (mean age = 64.4 years; mean education = 14.2 years) on a yes-no and a forced-choice recognition task for unfamiliar faces using the remember-know-guess procedure. Familiarity contributed more to forced-choice than to yes-no performance. Moreover, older participants, who showed a decrease in recollection together with an increase in familiarity, performed better on the forced-choice task than on the yes-no task, whereas younger participants showed the opposite pattern. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Priming of familiar and unfamiliar visual objects over delays in young and older adults.

Although priming of familiar stimuli is usually age invariant, little is known about how aging affects priming of preexperimentally unfamiliar stimuli. Therefore, this study investigated the effects of aging and encoding-to-test delays (0 min, 20 min, 90 min, and 1 week) on priming of unfamiliar objects in block-based priming paradigms. During the encoding phase, participants viewed pictures of novel objects (Experiments 1 and 2) or novel and familiar objects (Experiment 3) and judged their left–right orientation. In the test block, priming was measured using the possible–impossible object-decision test (Experiment 1), symmetric–asymmetric object-decision test (Experiment 2), and real–nonreal object-decision test (Experiment 3). In Experiments 1 and 2, young adults showed priming for unfamiliar objects at all delays, whereas older adults whose baseline task performance was similar to that of young adults did not show any priming. Experiment 3 found no effects of age or delay on priming of familiar objects; however, priming of unfamiliar objects was only observed in the young participants. This suggests that when older adults cannot rely on preexisting memory representations, age-related deficits in priming can emerge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Context effects in Stroop-like word and picture processing.

Presents a series of 6 experiments in which Stroop-like effects were generated by modally pure color–color, picture–picture, and word–word stimuli instead of the usual modally mixed color–word or picture–word stimuli. Naming, reading, and categorization tasks were applied. The Stroop inhibition was preserved with these stimuli but unexpectedly showed a semantic gradient only in the naming and not in the reading task. Word categorizing was slower and more interference prone than picture categorizing. These and other results can be captured by a model with two main assumptions: (a) semantic memory and the lexicon are separate, and (b) words have privileged access to the lexicon, whereas pictures and colors have privileged access to the semantic network. Such a model is developed and put to an initial test. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Semantic interference, orthographic facilitation, and their interaction in naming tasks.

The relative merits of 3 views on the cause of the Stroop-like semantic interference effect in naming tasks were investigated in 2 experiments. In the 1st experiment, which consisted of a picture-word interference task, the authors found the usual Stroop-like semantic interference effect for distractor words that were not orthographically related to the picture's name. However, the semantic interference effect was significantly reduced when the distractor words were orthographically related to the picture's name. The results were replicated in the 2nd experiment by using a different paradigm in which, instead of pictures, definitions were used as target stimuli. The results are interpreted as favoring one of the views: a word-form retrieval account of the semantic interference effect in naming tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age Differences in Implicit Memory: Conceptual, Perceptual, or Methodological?

The authors examined age differences in conceptual and perceptual implicit memory via word-fragment completion, word-stem completion, category exemplar generation, picture-fragment identification, and picture naming. Young, middle-aged, and older participants (N=60) named pictures and words at study. Limited test exposure minimized explicit memory contamination, yielding no reliable age differences and equivalent cross-format effects. In contrast, explicit memory and neuropsychological measures produced significant age differences. In a follow-up experiment, 24 young adults were informed a priori about implicit testing. Their priming was equivalent to the main experiment, showing that test trial time restrictions limit explicit memory strategies. The authors concluded that most implicit memory processes remain stable across adulthood and suggest that explicit contamination be rigorously monitored in aging studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual false recognition in Alzheimer's disease.

Previous research has found that patients with probable Alzheimer's disease (AD) show lower levels of false recognition of semantic associates than do healthy older adults. To investigate whether this finding is attributable to semantic impairments in patients with AD, the authors examined false recognition of perceptually related novel objects with little semantic content in patients with AD and healthy older adults. By using corrected recognition scores to control for unrelated false alarms, it was found that patients with AD showed lower levels of both true and false recognition of novel objects than did older adults. These results suggest that the previous difference in false recognition of semantic associates observed between patients with AD and older adults is not entirely attributable to semantic memory deficits in patients with AD but may also involve poorly developed gist information in these patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The spectrum of category effects in object and action knowledge in dementia of the Alzheimer's type.

The validity and origin of category effects in the anomia demonstrated by individuals with dementia of the Alzheimer's type (DAT) remains controversial. Twenty DAT subjects were tested with picture naming and semantic association judgement tests. Picture and word stimuli were drawn from biological, nonbiological, and actions–verbs categories, all of equal difficulty and previously normed on elderly controls. DAT subjects made significantly more naming and semantic judgement errors in the biological category than in the nonbiological category. They were relatively more accurate in naming and making judgements for actions–verbs when presented as words or as 5-s animations. When line drawings of actions were shown for naming, performance deteriorated significantly. Converging results from these 2 tasks provide strong evidence for a semantic memory impairment preferentially affecting biological items to a greater extent than nonbiological items or action verbs in DAT. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Naming and locating the tops of rotated pictures.

Investigated whether and how pictures are mentally rotated to upright before they can be named. Four experiments were conducted with 12 college students in each, who were given the tasks of naming pictures of common objects with various orientations and locating their tops. In the naming task, Ss required more time the farther the picture was from upright, but the rotation effect was reduced after Ss had named each picture once, indicating that rotation may be required only for unfamiliar stimuli. The top locating task was faster with upright figures, but otherwise-oriented pictures required the same time regardless of orientation. Top-locating was faster than naming, indicating that "topness" may be guessed even in unfamiliar figures, while naming also involves searching one's semantic memory for a name. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological mediators of the links among age, chronic illness, and everyday problem solving.

Reductions in everyday problem solving (EPS) are often reported in older age, although the underlying mechanisms remain unclear. The authors examined the role of 2 variables predicted to mediate (neuropsychological abilities and health status) or moderate (health status) the relationship between age and EPS performance. Toward these ends, they compared EPS and neuropsychological performance in 50 functionally independent adults with chronic kidney disease (CKD) and 64 control participants matched on age and education. Both older age and CKD were associated with worse performance on measures of EPS and memory/executive abilities. Neuropsychological abilities were positively associated with EPS performance. In both the full sample and control participants only, memory/executive functioning mediated the association between presence of chronic illness and EPS. Furthermore, memory/executive functioning partially mediated the link between age and EPS. Findings indicate that relations among age, health status, and EPS are not straightforward. Although performance on neuropsychological measures appeared to underlie EPS declines in chronic illness, increasing age remained independently associated with reduced EPS. The authors discuss implications for models of adult developmental changes in everyday cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Questioning the Living/Nonliving Dichotomy: Evidence From a Patient With an Unusual Semantic Dissociation.

In this article the authors describe a patient (J.P.) whose category-specific naming deficit eluded the classical dichotomies between living versus nonliving items or visual versus functional attributes. At age 22, he had herpes simplex encephalitis followed by a left temporal lobectomy. J.P. was tested on measures of visual perception, category naming, fluency, and name-picture matching. He showed a severe impairment naming and identifying fruits, vegetables, and musical instruments. His performance with animals and birds was spared inconsistently, meaning that even the preserved categories were, at some point, affected. J.P.'s unusual deficit supports the hypothesis that semantic knowledge is organized in the brain on the basis of object properties, which can cut across the living-nonliving categorical distinction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Object naming and semantic knowledge in temporal lobe epilepsy.

Object-naming impairment is common among temporal lobe epilepsy (TLE) patients, but other aspects of semantic memory have received limited attention in this population. This study examined object-naming ability and depth of semantic knowledge in healthy controls (n?=?29) and patients with early onset TLE (n?=?21). After administration of the Boston Naming Test (BNT), the authors asked participants to provide detailed definitions of 6 BNT objects. The TLE group demonstrated a significant deficit relative to controls in both object-naming ability and semantic knowledge for the target objects, even after controlling for IQ. In a multiple regression analysis that included other neuropsychological test scores as independent variables, the semantic knowledge score was the only significant predictor of patients' object-naming performance. Thus, at the group level, early onset TLE patients have a semantic knowledge deficit that contributes to dysnomia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The more you know the less you can tell: inhibitory effects of visuo-semantic activation on modality specific visual misnaming

WH, a 77-years old right-handed psychoanalyst, displayed modality specific visual misnaming as a sequel of an embolic stroke in the left posterior cerebral artery. WH's errors in visual object naming consisted mainly of semantic paraphasias and perseverations. His verbalizations during testing sometimes manifested a conflict between correct responses and perseverations. Analysis of the stream of information from visual perception via semantics to phonology suggested incomplete access from vision to semantics as the source of errors. The disconnection did not affect verbo-visual matching, though he was unable to reject names that did not correspond to visual stimuli. Action naming was relatively spared, but naming of pictures of actions with objects was worse than naming of pictures of intransitive actions. Tactile naming worsened with simultaneous vision of objects. In visual object naming the error rate increased with increasing familiarity of objects. We propose that an interaction of excitation and inhibition within a single semantic system can explain the clinical phenomena of modality specific visual misnaming.     

Self-referencing enhances memory specificity with age.

Self-referencing has been identified as an advantageous mnemonic strategy for young and older adults. However, little research has investigated the ways in which self-referencing may influence older adults' memory for details, which is typically impaired with age, beyond memory for the item itself. Experiment 1 assessed the effects of self- and other-referencing on memory for visually detailed pictures of objects in thirty-two young and thirty-two older adults. Results indicate that self- and close other-referencing similarly enhance general (item) and specific (detail) recognition for both young and older adults relative to the distant other condition. Experiment 2 extended these findings to source memory, with young and older adults encoding verbal information in self-referent, semantic, and structural conditions. Findings suggest that self-referencing provides an age-equivalent boost in general memory and specific memory for specific source details. We conclude that the mnemonic benefits of referencing the self extend to specific memory for visual and verbal information across the lifespan. (PsycINFO Database Record (c) 2011 APA, all rights reserved)