Age Effects on Visual-Perceptual Processing and Confrontation Naming*

ABSTRACT

The impact of age-related changes in visual-perceptual processing on naming ability has not been reported. The present study investigated the effects of 6 levels of spatial frequency and 6 levels of contrast on accuracy and latency to name objects in 14 young and 13 older neurologically normal adults with intact lexical-semantic functioning. Spatial frequency and contrast manipulations were made independently. Consistent with the hypotheses, variations in these two visual parameters impact naming ability in young and older subjects differently. The results from the spatial frequency-manipulations revealed that, in general, young vs. older subjects are faster and more accurate to name. However, this age-related difference is dependent on the spatial frequency on the image; differences were only seen for images presented at low (e.g., 0.25–1 c/deg) or high (e.g., 8–16 c/deg) spatial frequencies. Contrary to predictions, the results from the contrast manipulations revealed that overall older vs. young adults are more accurate to name. Again, however, differences were only seen for images presented at the lower levels of contrast (i.e., 1.25%). Both age groups had shorter latencies on the second exposure of the contrast-manipulated images, but this possible advantage of exposure was not seen for spatial frequency. Category analyses conducted on the data from this study indicate that older vs. young adults exhibit a stronger nonliving-object advantage for naming spatial frequency-manipulated images. Moreover, the findings suggest that bottom-up visual-perceptual variables integrate with top-down category information in different ways. Potential implications on the aging and naming (and recognition) literature are discussed.     

Diagnosis of cognitive impairment onset in older adults based on limitations in language skills / Diagnóstico del inicio del deterioro cognitivo en mayores a partir de limitaciones en las capacidades lingüísticas

Abstract

Progressive decline in language has been described in neuropsychological studies on Alzheimer’s disease and Mild Cognitive Impairment (MCI). We investigate this decline in its early stages, as well as its manifestations and the linguistic differences between participants at risk of developing MCI and without impairment. Participants were 36 older adults, all aged over 65. They were assessed using 31 subtests grouped into eight areas: fluency, comprehension, oral expression, reading, writing, memory, perceptual organization and processing speed. Our results showed significant differences between participants at risk of developing MCI and without impairment in verbal tests but not in manipulative tests. All participants at risk of developing MCI scored lowest in these eight areas. Our findings illustrate the relevance of investigating language skills in people at risk of developing MCI. Investigating these neuropsychological changes will help design appropriate intervention programmes that affect areas with higher levels of impairment.     

The role of historical intuitions in children's and adults' naming of artifacts

It is commonly assumed that artifacts are named solely on the basis of properties they currently possess; in particular, their appearance and function. The experiments presented here explore the alternative proposal that the history of an artifact plays some role in how it is named. In three experiments, children between the ages of 4 and 9 years and adults were presented with familiar artifacts whose appearance and function were then radically altered. Participants were tested as to whether they believed that the modified objects were still members of the artifact kind. Results indicate that object history becomes increasingly important over the course of development.     

Equivalence relations, contextual control, and naming

This paper reports two experiments that investigated the role of verbal behavior in the emergence and generalization of contextually controlled equivalence classes. During both experiments, participants were trained with two different combinations of the same easily nameable, yet formally unrelated, pictorial stimuli. Match-to-sample baselines for eight four-member classes were established under the contextual control of two colors. In the presence of one color, conditional relations were established between stimuli whose normative names rhymed. In the presence of the other color, conditional relations were established between stimuli whose normative names did not rhyme. Although, during Experiment 1, all participants demonstrated equivalence classes involving rhyming stimuli, none demonstrated the formation of nonrhyme equivalence classes. To investigate this finding, Experiment 2 evaluated whether participants would demonstrate both rhyme and nonrhyme equivalence classes given more extensive exposure to the experimental contingencies. All participants demonstrated contextually controlled rhyme and nonrhyme equivalence classes, although rhyme classes were demonstrated with greater facility than nonrhyme classes. Results indicate that visual stimuli are named, that verbal bases for stimulus classification can affect the emergence of contextually controlled equivalence classes, and that untrained contextually controlled conditional discriminations involving novel stimuli can emerge on the basis of participants' verbal behavior.     

Interactive imagery and colour in paired-associate learning

In four experiments participants were instructed to imagine scenes that described either an animal interacting with a coloured object or scenes in which the animal and coloured object were independent of each other. Participants were then given the name of the animal and required to select the name of the object and its colour. The results showed that the classic interactive imagery effect was greater for the selection of the name of the object than it was for colour. In Experiments 2, 3, and 4, additional measures were taken which suggest that the effect for colour is dependent upon the retrieval of other features of the object (e.g., its form). Thus it is argued that there is no primary interactive imagery effect for colour. The results were predicted by a version of the shared information hypothesis. The implications of the results for alternative theories are also considered.     

Cumulative semantic inhibition in picture naming: experimental and computational studies

We report an experiment in which subjects named 120 pictures, consisting of series of five pictures drawn from each of 24 semantic categories (and intermixed with 45 fillers). The number of intervening trials (lag) between successive presentations of members of the same category varied from two to eight. Subjects' naming latencies were slowed by 30 ms for each preceding member of the category. This effect was both cumulative and linear, and unrelated to the lag elapsing since the previous presentation of a category member. These results definitively demonstrate the occurrence of cumulative interference for word retrieval by prior retrieval of other exemplars of the same semantic category-cumulative semantic inhibition. We claim that this inhibition effect could only occur if the spoken word production system possesses three specific properties (competition, priming, and sharing of semantic activation). We provide computational-modelling evidence in support of this claim. We show that no current theory of spoken word production has all of these properties. In their current form, all these theories are falsified by these results. We briefly discuss the obstacles that may be encountered by current models were they modified to account for our findings.     

Variable solutions to the same problem: aberrant practice effects in object naming by three aphasic patients

Although deficits in confrontation naming are a common consequence of damage to the language areas of the left cerebral hemisphere, some patients with aphasia show relatively good naming ability. We measured effects of repeated practice on naming latencies for a set of pictured objects by three aphasic patients with near-normal naming ability and by neurologically intact young and older adults. While the non-injured participants showed a systematic reduction in overall mean latencies and reduced trial-to-trial latency variability, the aphasic patients did not. Examination of the latency distributions suggests that successful naming by aphasic patients may come about by different underlying operations.     

Is action naming better preserved (than object naming) in Alzheimer's disease and why should we ask?

The present study compared object and action naming in patients with Alzheimer's dementia. We tested the hypothesis put forward in (some) previous studies that in Alzheimer's dementia the production of verbs, that is required in action naming, is better preserved than the production of nouns, that is required in object naming. The possible reason for the dissociation is that verbs are supported predominantly by frontal brain structures that may remain relatively better preserved in early Alzheimer's disease. Objects, on the other hand, are supported by temporal lobe structures that are affected early in the disease. An alternative hypothesis, which is supported by other studies, is that action naming is more impaired than object naming due to verbs being semantically more complex than nouns. In order to test these contrasting hypotheses, the present study used more stringent methodology than previous studies. We used a larger set of stimuli with carefully matched object and action items and we collected not only accuracy data but also naming latencies, a measure that is sensitive to even mild lexical retrieval problems. We compared the performance of 19 patients with mild to moderate Alzheimer's disease with that of 19 healthy age matched participants. We found that both the patients and the comparison group responded faster and made fewer errors on the object pictures than the action pictures. A qualitative analysis of the naming errors indicated that object and action naming pose different demands for the language system. The results overall suggest that the patients' performance is an exaggeration of the pattern present in the comparison participants.     

Contributions of response set and semantic relatedness to cross-modal Stroop-like picture-word interference in children and adults

Resistance to interference from irrelevant auditory stimuli undergoes development throughout childhood. To test whether semantic processes account for age-related changes in a Stroop-like picture-word interference effect, children (3- to 12-year-olds) and adults named pictures while listening to words varying in terms of semantic relatedness to the pictures and response set membership. In Experiments 1 and 2, with animal and clothing pictures, the interference effect observed in children, but not in adults, depended on the distractors' status as members of the response set. In Experiment 3, with unrelated pictures, adults, but not children, showed greater interference for trials with distractors in the response set. These results indicate developmental changes in picture-word interference involving the establishment of a response set in working memory.     

Differential vocalization in budgerigars: towards an experimental analysis of naming.

In Experiment 1, 3 budgerigars (Melopsittacus undulatus) were trained with food reinforcement to make low- or high-frequency calls in response to different color stimuli, C1 and C2 (a color-naming task), using a gradual response-differentiation procedure and an automatic call-recognition system. Thus, a call within a certain frequency band was reinforced in the presence of C1 ("C1 call"), and a call within a different band was reinforced in the presence of C2 ("C2 call"). In Experiment 2, all 3 budgerigars were trained in a form-to-color matching-to-sample task, alternating trial by trial with either the color-naming task (2 birds) or an identity color matching-to-sample task (1 bird). Sample stimuli for the new matching-to-sample task were forms (F1 or F2) and comparisons were the same two colors (C1 and C2). Given Sample F1 or F2, birds had to make a call to produce Comparison Pair C1 and C2. With F1 as the sample, a peck on C1 was reinforced; with F2 as the sample, a peck on C2 was reinforced. Although no particular call was specified in the presence of F1 and F2, 2 birds made the C1 call in the presence of F1 and the C2 call in the presence of F2. In Experiment 3, the bird that failed to match form and color calls in Experiment 2 and another bird were first trained in a color-to-form matching-to-sample task: C1 to F3 and C2 to F4. In this task, to produce the comparison pair of forms, a high call (or low for the other bird) was required in the presence of C1, and a low call (or high) was required in the presence of C2. Both birds were then trained with an identity matching-to-sample task in which sample and comparison stimuli were the same two forms, F3 and F4. Trials on the identity task alternated with the color-to-form trials. Although no particular call was required in the presence of Samples F3 and F4, both birds came to make the C1 call in the presence of F3 and the C2 call in the presence of F4. Our technique promises to be useful for the study of emergent vocal relations in budgerigars and other animals.