Age differences in sentence production

This is an electronic version of an article published in J Gerontol B Psychol Sci Soc Sci (2003) 58 (5): P260-P268. doi: 10.1093/geronb/58.5.P260Two experiments have been completed using experimental techniques to study language production under controlled conditions. In Experiment 1, young and older adults were given two, three, or four words and asked to compose a sentence. Older adults' responses were similar to those of young adults when given two or three words. When given four words, the older adults made more errors and their responses were shorter and less elaborate than those of the young adults. In Experiment 2, simple intransitive verbs (smiled), transitive verbs (replaced), and complement-taking verbs (expected) were contrasted. The responses of older adults were similar to those of young adults given intransitive and transitive verbs. Given complement-taking verbs, young adults produced complex sentences, whereas the older adults produced simpler, less complex sentences; the older adults also made many errors. Both experiments found that older adults respond more slowly than young adults

The Costs of Doing Two Things at Once for Young and Older Adults: Talking while Walking, Finger Tapping, and Ignoring Speech or Noise

This article may not exactly replicate the final version published in the APA journal. It is not the copy of recordYoung and older adults provided language samples in response to questions while walking, finger tapping, and ignoring speech or noise. The language samples were scored on 3 dimensions: fluency, complexity, and content. The hypothesis that working memory limitations affect speech production by older adults was tested by comparing baseline samples with those produced while the participants were performing the concurrent tasks. There were baseline differences: Older adults' speech was less fluent and less complex than young adults' speech. Young adults adopted a different strategy in response to the dual-task demands than older adults: They reduced sentence length and grammatical complexity. In contrast, older adults shifted to a reduced speech rate in the dual-task conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved

Sentence production by younger and older adults in controlled contexts

This is an electronic version of an article published in J Gerontol B Psychol Sci Soc Sci (2004) 59 (5): P220-P224. doi: 10.1093/geronb/59.5.P220In this experiment we compared young and older adults' abilities to produce complex sentences under controlled conditions. We asked participants to memorize sentence stems differing in syntactical complexity and then to produce a complete sentence using the stem. The length, complexity, and content of young adults' responses varied with the syntactical complexity of the stems, whereas older adults' responses did not. These results suggest that working memory processing limitations impose a “ceiling” on older adults' production of complex sentences, limiting their length, complexity, and content

Revealing language deficits following stroke: the cost of doing two things at once

This is an electronic version of an article published in Kemper, S., McDowd, J., Pohl, P., Herman, R., & Jackson, S. (2006). Revealing language deficits following stroke: the cost of doing two things at once. Aging, Neuropsychology, and Cognition, 13, 115-139. PM#16766346. Aging, Neuropsychology, and Cognition is available online at www.taylorandfrancis.comThe costs of doing two things were assessed for a group of healthy older adults and older adults who were tested at least 6 months after a stroke. A baseline language sample was compared to language samples collected while the participants were performing concurrent motor tasks or selective ignoring tasks. Whereas the healthy older adults showed few costs due to the concurrent task demands, the language samples from the stroke survivors were disrupted by the demands of doing two things at once. The dual task measures reveal long-lasting effects of strokes that were not evident when stroke survivors were assessed using standard clinical tools

Aging and the vulnerability of speech to dual task demands

This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.Tracking a digital pursuit rotor task was used to measure dual task costs of language production by young and older adults. Tracking performance by both groups was affected by dual task demands: time on target declined and tracking error increased as dual task demands increased from the baseline condition to a moderately demanding dual task condition to a more demanding dual task condition. When dual task demands were moderate, older adults' speech rate declined but their fluency, grammatical complexity, and content were unaffected. When the dual task was more demanding, older adults' speech, like young adults' speech, became highly fragmented, ungrammatical, and incoherent. Vocabulary, working memory, processing speed, and inhibition affected vulnerability to dual task costs: vocabulary provided some protection for sentence length and grammaticality, working memory conferred some protection for grammatical complexity, and processing speed provided some protection for speech rate, propositional density, coherence, and lexical diversity. Further, vocabulary and working memory capacity provided more protection for older adults than for young adults although the protective effect of processing speed was somewhat reduced for older adults as compared to the young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved

The Effects of Varying Task Priorities on Language Production by Young and Older Adults

The present study compared how varying task priorities affected young and older adults' language production. Both young and older adults responded to monetary incentives to vary their performance when simultaneously talking and tracking a pursuit rotor. Tracking performance improved when they were rewarded for tracking and declined when they were rewarded for talking. Both young and older adults also spoke more slowly when rewarded for tracking and more rapidly when rewarded for talking. Young produced less complex sentences when rewarded for tracking and produced more complex sentences when rewarded for talking. However, older adults did not vary their grammatical complexity as a function of monetary incentives. These results are consistent with prior studies suggesting that older adults use a simplified speech register in response to dual-task demands

Tracking Talking: Dual Task Costs of Planning and Producing Speech for Young versus Older Adults

A digital pursuit rotor was used to monitor speech planning and production costs by time-locking tracking performance to the auditory wave form produced as young and older adults were describing someone they admire. The speech sample and time-locked tracking record were segmented at utterance boundaries and multilevel modeling was used to determine how utterance-level predictors such as utterance duration or sentence grammatical complexity and person-level predictors such as speaker age or working memory capacity predicted tracking performance. Three models evaluated the costs of speech planning, the costs of speech production, and the costs of speech output monitoring. The results suggest that planning and producing propositionally dense utterances is more costly for older adults and that older adults experience increased costs as a result of having produced a long, informative, or rapid utterance

Automatic measurement of propositional idea density from part-of-speech tagging

The original publication is available at www.springerlink.comThe Computerized Propositional Idea Density Rater (CPIDR, pronounced “spider”) is a computer program that determines the propositional idea density (P-density) of an English text automatically on the basis of partof-speech tags. The key idea is that propositions correspond roughly to verbs, adjectives, adverbs, prepositions, and conjunctions. After tagging the parts of speech using MontyLingua (Liu, 2004), CPIDR applies numerous rules to adjust the count, such as combining auxiliary verbs with the main verb. A “speech mode” is provided in which CPIDR rejects repetitions and a wider range of fillers. CPIDR is a user-friendly Windows .NET application distributed as open-source freeware under GPL. Tested against human raters, it agrees with the consensus of two human raters better than the team of five raters agree with each other [r(80) = .97 vs. r(10) = .82, respectively]

The Northern Eurasia Earth Science Partnership: An Example of Science Applied to Societal Needs

Northern Eurasia, the largest landmass in the northern extratropics, accounts for ~20% of the global land area. However, little is known about how the biogeochemical cycles, energy and water cycles, and human activities specific to this carbon-rich, cold region interact with global climate. A major concern is that changes in the distribution of land-based life, as well as its interactions with the environment, may lead to a self-reinforcing cycle of accelerated regional and global warming. With this as its motivation, the Northern Eurasian Earth Science Partnership Initiative (NEESPI) was formed in 2004 to better understand and quantify feedbacks between northern Eurasian and global climates. The first group of NEESPI projects has mostly focused on assembling regional databases, organizing improved environmental monitoring of the region, and studying individual environmental processes. That was a starting point to addressing emerging challenges in the region related to rapidly and simultaneously changing climate, environmental, and societal systems. More recently, the NEESPI research focus has been moving toward integrative studies, including the development of modeling capabilities to project the future state of climate, environment, and societies in the NEESPI domain. This effort will require a high level of integration of observation programs, process studies, and modeling across disciplines

The effects of aging and dual task performance on language production

This is an electronic version of an article published in Kemper, S., Schmalzried, R., Herman, R., Leedahl, S., & Mohankumar, D. (2009). The effects of aging and dual task performance on language production. Aging, Neuropsychology, and Cognition, 16, 241-259. PM#2674132. Aging, Neuropsychology, and Cognition is available online at www.taylorandfrancis.comA digital pursuit rotor task was used to measure dual task costs of language production by young and older adults. After training on the pursuit rotor, participants were asked to track the moving target while providing a language sample. When simultaneously engaged, young adults experienced greater dual task costs to tracking, fluency, and grammatical complexity than older adults. Older adults were able to preserve their tracking performance by speaking more slowly. Individual differences in working memory, processing speed, and Stroop interference affected vulnerability to dual task costs. These results demonstrate the utility of using a digital pursuit rotor to study the effects of aging and dual task demands on language production and confirm prior findings that young and older adults use different strategies to accommodate to dual task demands