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Effects of age and dementia on temporal cycles in spontaneous speech fluency

Spontaneous speech of healthy adults consists of alternating periods of fluent and hesitant segments, forming temporal cycles in speech fluency. The regularity of these cycles may be related to the functioning of brain networks during speech planning and execution. This paper investigates the theoretical link between human cognitive functioning and temporal cycles in speech production using a quantitative time series analysis to characterize the regularity and frequency of temporal cycles in adults with differing levels and etiology of cognitive decline. We compare spontaneous speech of adults without a neurological diagnosis, both older and younger, to that of adults with frontotemporal lobar degeneration (FTLD). Two measures of temporal cycle frequency (mean and mode) calculated from the power spectrum of speech fluency represented as a time series were found to be associated with subjects’ age, regardless of diagnosis of dementia. Two measures of periodicity (g-statistic and rhythmicity-index), as well as mean frequency, differentiated between adults with and without dementia. Our study confirms the presence of regular temporal cycles in spontaneous speech and suggests that temporal cycle characteristics are affected in different ways by declines in cognitive functioning due to dementia and aging.

from the Journal of Neurolinguistics

Does Audiovisual Speech Offer a Fountain of Youth for Old Ears? An Event-Related Brain Potential Study of Age Differences in Audiovisual Speech Perception

The current study addressed the question whether audiovisual (AV) speech can improve speech perception in older and younger adults in a noisy environment. Event-related potentials (ERPs) were recorded to investigate age-related differences in the processes underlying AV speech perception. Participants performed an object categorization task in three conditions, namely auditory-only (A), visual-only (V), and AVspeech. Both age groups revealed an equivalent behavioral AVspeech benefit over unisensory trials. ERP analyses revealed an amplitude reduction of the auditory P1 and N1 on AVspeech trials relative to the summed unisensory (A + V) response in both age groups. These amplitude reductions are interpreted as an indication of multisensory efficiency as fewer neural resources were recruited to achieve better performance. Of interest, the observed P1 amplitude reduction was larger in older adults. Younger and older adults also showed an earlier auditory N1 in AVspeech relative to A and A + V trials, an effect that was again greater in the older adults. The degree of multisensory latency shift was predicted by basic auditory functioning (i.e., higher hearing thresholds were associated with larger latency shifts) in both age groups. Together, the results show that AV speech processing is not only intact in older adults, but that the facilitation of neural responses occurs earlier in and to a greater extent than in younger adults. Thus, older adults appear to benefit more from additional visual speech cues than younger adults, possibly to compensate for more impoverished unisensory inputs because of sensory aging.

from Psychology and Aging

Effects of Age, Speed of Processing, and Working Memory on Comprehension of Sentences With Relative Clauses

Two hundred participants, 50 in each of four age ranges (19–29, 30–49, 50–69, 70–90) were tested for working memory, speed of processing, and the processing of sentences with relative clauses. In Experiment 1, participants read four sentence types (cleft subject, cleft object, subject-subject, subject-object) in a word-by-word, non-cumulative, self-paced reading task and made speeded plausibility judgments about them. In Experiment 2, participants read two types of sentences, one of which contained a doubly center embedded relative clause. Older participants’ comprehension was less accurate and there was age-related slowing of online processing times in all but the simplest sentences, which increased in syntactically complex sentences in Experiment 1. This pattern suggests an age-related decrease in the efficiency of parsing and interpretation. Slower speed of processing and lower working memory were associated with longer online processing times only in Experiment 2, suggesting that task-related operations are related to general speed of processing and working memory. Lower working memory was not associated with longer reading times in more complex sentences, consistent with the view that general working memory is not critically involved in online syntactic processing. Longer online processing at the most demanding point in the most demanding sentence was associated with better comprehension, indicating that it reflects effective processing under some certain circumstances. However, the poorer comprehension performance of older individuals indicates that their slower online processing reflects inefficient processing even at these points.

from Psychology and Aging

The Specificity of Age-Related Decline in Interpretation of Emotion Cues From Prosody

Older adults are not as good as younger adults at decoding prosodic emotions. We sought to determine the specificity of this finding. Performance of older and younger adults was compared on a prosodic emotion task, a “pure” prosodic emotion task, a linguistic prosody task, and a “pure” linguistic prosody task. Older adults were less accurate at interpreting prosodic emotion cues and nonemotional contours, concurrent semantic processing worsened interpretation, and performance was further degraded when identifying negative emotions and questions. Older adults display a pervasive problem interpreting prosodic cues, but further study is required to clarify the stage at which performance declines.

from Psychology and Aging

Older Adults Expend More Listening Effort Than Young Adults Recognizing Speech in Noise

Conclusions: Older adults require more processing resources to understand speech in noise. Dual-task measures and subjective ratings tap different aspects of listening effort.

from the Journal of Speech, Language, and Hearing Research

Story Processing Ability in Cognitively Healthy Younger and Older Adults

Conclusions: The relationship between adults’ comprehension of stimuli used to elicit narrative production samples and their narrative productions differed across the life span, suggesting that discourse processing performance changes in healthy aging. Finally, the study’s findings suggest that memory and attention contribute to older adults’ story processing performance.

from the Journal of Speech, Language, and Hearing Research

Older Learners in SLA Research: A First Look at Working Memory, Feedback, and L2 Development

A great deal of research into second-language (L2) development focuses on the role of cognitive factors and other individual differences. Studies of children and prime-of-life adult L2 learners suggest that differences exist in the learning processes of these groups. However, to date, little empirical work has been conducted with older adult learners. In this article we argue that older adults’ L2 learning aptitudes, processes, and outcomes merit investigation. We present interaction and working memory (WM) research as a case in point and then, as a preliminary illustration, report on a small-scale study of nine older adults, age 65–89, who were native speakers of Spanish learning English as a second language. These learners carried out communicative tasks with native speakers of English, who provided interactional feedback in response to nontargetlike question forms. Interestingly, the only older learners who showed L2 development were those with the highest scores on a first-language listening-span test of WM. We conclude by proposing that larger scale longitudinal research into the often overlooked population of older L2 learners is likely to shed interesting light on important questions concerning WM and learning processes in the field of second language acquisition.

from Language Learning

Pharyngeal Pressure Generation During Tongue-Hold Swallows Across Age Groups

Conclusions: The tongue-hold maneuver affects oropharyngeal and hypopharyngeal pressure in the young and elders in similar ways, whereas effects on UES peak relaxation pressure differ between age groups. Reduced pharyngeal peak pressure and increased UES relaxation pressure underscore the notion that tongue-hold swallows should not be performed when bolus is present. Long-term training effects remain to be investigated.

from American Journal of Speech Language Pathology

Effects of Automatic/Controlled Access Processes on Semantic Memory in Alzheimer’s Disease

This study examines the impact of automatic/controlled access processes on the semantic network in 30 patients with Alzheimer’s disease (AD). The AD group was compared with a control group using a battery of neuropsychological tests, a variation of Hodges’s semantic testing battery, designed to assess semantic knowledge. The AD group had markedly lower scores than the normal group on each semantic test, but with a different degree of deterioration depending on the nature of the processes (controlled/automatic) in accessing the semantic network. AD patients had poorer performances on the explicit semantic tasks mainly involving controlled-process access (e.g., the WAIS Similarities Subtest) than those involving mainly automatic-process access (e.g., the Verbal Automatism test). Analyses of confidence intervals allowed a gradient of impaired performances in increasing order to be elaborated: a) the Verbal Automatism test, b) the WAIS Vocabulary Subtest, c) the WAIS Information Subtest, d) the Letter Fluency Task, e) Naming as a Response to Definition, f) the Category Fluency Task, g) the WAIS Similarities Subtest, and h) the Oral Denomination 80 Test. The results of our study suggest that explicit semantic tasks needing passive or automatic processes to access semantic memory would be better preserved in AD.

from the Journal of Alzheimer’s Disease

Recognition of Rapid Speech by Blind and Sighted Older Adults

Conclusions: The findings support the notion that older blind adults recognize time-compressed speech considerably better than older sighted adults in quiet and noise. Their performance levels are similar to those of younger adults, suggesting that age-related difficulty in understanding time-compressed speech is not an inevitable consequence of aging. Instead, frequent listening to speech at rapid rates, which was highly correlated with performance of the older blind adults, may be a useful technique to minimize age-related slowing in speech understanding.

from the Journal of Speech, Language, and Hearing Research

Recognition of Rapid Speech by Blind and Sighted Older Adults

Conclusions: The findings support the notion that older blind adults recognize time-compressed speech considerably better than older sighted adults in quiet and noise. Their performance levels are similar to those of younger adults, suggesting that age-related difficulty in understanding time-compressed speech is not an inevitable consequence of aging. Instead, frequent listening to speech at rapid rates, which was highly correlated with performance of the older blind adults, may be a useful technique to minimize age-related slowing in speech understanding.

from the Journal of Speech, Language, and Hearing Research

The Structure of Working Memory Abilities Across the Adult Life Span

The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20–89 (n = 388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domain-differentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation.

from Psychology and Aging

Use of Hearing Aids and Assistive Listening Devices in an Older Australian Population

Conclusions:

These results indicate that hearing aid ownership and ALD usage remains low in the older population. Given the significant proportion of older people who self-report and have a measured hearing loss, it is possible that more could be helped through the increased use of hearing aid and/or ALD technology. Greater efforts are needed to promote the benefits of these technologies and to support their use among older people with hearing loss.

from the Journal of the American Academy of Audiology

Temporal processing as a base for language universals: Cross-linguistic comparisons on sequencing abilities with some implications for language therapy

We propose the existence of a neural mechanism underlying the perception of rapid changes in non-verbal acoustic features which constitute a frame for speech perception in many languages. This finding may be important with respect to future applications of temporal training in speech therapy programs designed for patients with receptive language disorders of different etiologies.<p><p>from <a href=”Restorative” _mce_href=”http://iospress.metapress.com/content/v53q8p4r75k32171/”><em>Restorative”>http://iospress.metapress.com/content/v53q8p4r75k32171/”><em>Restorative Neurology and Neuroscience </em></a></p>

Bias of quantifier scope interpretation is attenuated in normal aging and semantic dementia

Many sentences with two quantifiers exhibit a phenomenon known as “quantifier scope ambiguity.” Consider the example A unicorn ran through every garden, which contains the quantifiers “a” and “every.” Most speakers of English agree that it may refer to one or more than one unicorn. Very little previous work has evaluated the ability of brain-damaged or aphasic patients to interpret such sentences. We administered a sentence-reading task with picture verification to a group of semantic dementia patients (N = 5) and a matched group of cognitively normal controls (N = 23). Controls exhibited a tendency to interpret the word every as having wide scope regardless of the order of quantifiers, as evidenced by decreased reaction time and increased accuracy when verifying pictures that required this interpretation. This bias was attenuated by increasing age and by the presence of semantic dementia. Furthermore, higher FAS fluency scores were associated with slower responses and more errors, while higher semantic fluency scores were associated with the opposite pattern. These findings fit best with a model in which the initial products of linguistic analysis are underspecified and biases in their interpretation arise subsequently through frontally mediated logical or pragmatic reasoning.

from the Journal of Neurolinguistics