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PubMed1995

The natural history of Alzheimer's disease: a brain bank study.

OBJECTIVE: To define the natural history of Alzheimer's Disease (AD), from time of clinical (presumptive) diagnosis and/or onset of symptoms to death and to describe demographic and clinical characteristics of patients with AD. DESIGN: Retrospective medical records review. SETTING: Regional brain bank operated by a university hospital. PARTICIPANTS: One-hundred randomly selected, autopsy-confirmed Alzheimer's Disease patients. MEASUREMENTS: All information pertaining to family and clinical history (diagnoses, office visits, hospitalizations), medication use, nutritional status, and clinical testing (laboratory testing, imaging, diagnostics, and psychometric testing) was abstracted. Time of onset for behavioral symptoms (e.g., anxiety, wandering, agitation) and deficits in cognitive function (e.g., recent memory, concentration, language) and activities of daily living (ADL) were also abstracted. Data was collected on-site using a laptop computer and a series of customized data entry spreadsheets. Upon completion of the data abstraction process, data was converted to a database program for query and analysis. RESULTS: A complete natural history timeline was constructed based on the mean values observed in order to demonstrate important clinical endpoints, namely, diagnosis, institutionalization, and death. The mean time between onset of symptoms and clinical diagnosis was 32.1 months (standard deviation = 37.9 months). The interval between symptom onset and AD diagnosis was longer for patients who were less than 65 at time of diagnosis (mean = 37.6 months), female patients (mean = 34.9 months), and patients with a positive family history of dementia (mean = 37.5 months). The mean age at diagnosis was 74.7 years (standard deviation = 8.6 years), with a range of 52 to 89 years. Most patients were diagnosed between the ages of 70 and 79. Males were diagnosed at an earlier age, 72.8 years, on average, than females, 75.4 years. The mean time to institutionalization from time of clinical diagnosis was 23.9 months (standard deviation = 33.6 months). The average age at institutionalization was 77.6 years, with a minimum of 60 years and a maximum of 92.5 years. Institutionalization occurred 56.5 months after symptom onset, on average. This interval was shorter among patients with a negative family history (mean = 53.1 months) and patients diagnosed after age 65 (mean = 51.6 months). Patients diagnosed before age 65 experienced a significantly greater average time to institutionalization, 94 months (P = .01). Disease duration was measured as time from symptom onset until death. Mean disease duration was 101.3 months, or nearly 8.5 years (standard deviation = 59.2 months). Subgroup analysis showed that disease duration was prolonged in younger onset patients (mean = 129.1 months), females (mean = 107.9 months), and patients with a positive family history of dementia (mean = 106.3 months). CONCLUSIONS: These data suggest that the typical AD patient is diagnosed 32 months after symptom onset, at the age of 75 years. This patient is institutionalized 25 months after diagnosis, or approximately 57 months after symptom onset at age 78. The patient remains institutionalized for 44 months or, in actuality, until death. Total disease duration for this typical AD patient is just over 101 months, or approximately 8.5 years.

Activities of Daily Living↗

PubMed2004

Deficits for semantics and the irregular past tense: a causal relationship?

The regular and irregular past tense has become a focus for recent debates about the structure of the language processing system, asking whether language functions are subserved by different neural and functional mechanisms or whether all processes can be accommodated within a single unified system. A critical claim of leading single mechanism accounts is that the relationship between an irregular stem and its past tense form is primarily semantic and not morphological in nature. This predicts an obligatory relationship between semantic performance and access to the irregular past tense, such that a semantic deficit necessarily leads to impairments on the irregulars. We tested this claim in a series of studies probing the comprehension and production of regular and irregular past tense forms in four semantic dementia patients, all of whom had profound semantic deficits. In two elicitation tasks and one auditory priming study, we found that three out of the four patients did not have a deficit for the irregular past tense, in spite of their semantic deficits. This argues against the view that the relationship between irregular past tense forms and their stems is primarily semantic, and more generally against the single system claim that morphological structure can be captured solely based on phonological and semantic relationships.

Aged↗

PubMed2004

Language experience and the organization of brain activity to phonetically similar words: ERP evidence from 14- and 20-month-olds.

The ability to discriminate phonetically similar speech sounds is evident quite early in development. However, inexperienced word learners do not always use this information in processing word meanings [Stager & Werker (1997). Nature, 388, 381-382]. The present study used event-related potentials (ERPs) to examine developmental changes from 14 to 20 months in brain activity important in processing phonetic detail in the context of meaningful words. ERPs were compared to three types of words: words whose meanings were known by the child (e.g., ''bear''), nonsense words that differed by an initial phoneme (e.g., ''gare''), and nonsense words that differed from the known words by more than one phoneme (e.g., ''kobe''). These results supported the behavioral findings suggesting that inexperienced word learners do not use information about phonetic detail when processing word meanings. For the 14-month-olds, ERPs to known words (e.g., ''bear'') differed from ERPs to phonetically dissimilar nonsense words (e.g., ''kobe''), but did not differ from ERPs to phonetically similar nonsense words (e.g., ''gare''), suggesting that known words and similar mispronunciations were processed as the same word. In contrast, for experienced word learners (i. e., 20-month-olds), ERPs to known words (e.g., ''bear'') differed from those to both types of nonsense words (''gare'' and ''kobe''). Changes in the lateral distribution of ERP differences to known and unknown (nonce) words between 14 and 20 months replicated previous findings. The findings suggested that vocabulary development is an important factor in the organization of neural systems linked to processing phonetic detail within the context of word comprehension.

Acoustic Stimulation↗

PubMed2005

Imaging speech production using fMRI.

Human speech is a well-learned, sensorimotor, and ecological behavior ideal for the study of neural processes and brain-behavior relations. With the advent of modern neuroimaging techniques such as positron emission tomography (PET) and functional magnetic resonance imaging (fMRI), the potential for investigating neural mechanisms of speech motor control, speech motor disorders, and speech motor development has increased. However, a practical issue has limited the application of fMRI to issues in spoken language production and other related behaviors (singing, swallowing). Producing these behaviors during volume acquisition introduces motion-induced signal changes that confound the activation signals of interest. A number of approaches, ranging from signal processing to using silent or covert speech, have attempted to remove or prevent the effects of motion-induced artefact. However, these approaches are flawed for a variety of reasons. An alternative approach, that has only recently been applied to study single-word production, uses pauses in volume acquisition during the production of natural speech motion. Here we present some representative data illustrating the problems associated with motion artefacts and some qualitative results acquired from subjects producing short sentences and orofacial nonspeech movements in the scanner. Using pauses or silent intervals in volume acquisition and block designs, results from individual subjects result in robust activation without motion-induced signal artefact. This approach is an efficient method for studying the neural basis of spoken language production and the effects of speech and language disorders using fMRI.

Adult↗

PubMed1996

An examination of impaired acoustic-phonetic processing in aphasia.

This research examines the nature of acoustic-phonetic impairments found in aphasia, and the reliability of patient performance on phoneme discrimination and identification tasks. Aphasic patients were tested on three phoneme discrimination tasks examining their ability to discriminate items on the basis of contrasts in sonorance, manner, place, or voicing using both spoken and synthetic stimuli. One of these tests involving the discrimination of spoken, one-syllable items was given to patients on three occasions over the course of 1 year to examine short- and long-term test reliability. In addition to these measures, patients were tested on three phoneme identification tasks using stimulus items drawn from the discrimination tests. The results of these tests show that aphasic patients may display stable patterns of performance on these measures over time and between tests. Furthermore, these findings suggest that discriminations of synthetic speech do not necessarily reflect patients' ability to discriminate spoken speech tokens. These results are interpreted as evidence that aphasics display stable, discrete impairments in acoustic-phonetic processing, and that these deficits may be measured reliably using phoneme discrimination and identification tasks using natural speech.

Adult↗

PubMed2000

Knowledge, skills, and behavior improvements on peer educators and low-income Hispanic participants after a stage of change-based bilingual nutrition education program.

A nutrition education program, entitled La Cocina Saludable, was designed according to the Stage of Change Model and implemented in ten southern Colorado counties. The objectives were to improve the nutrition related knowledge, skills, and behaviors that lead to healthy lifestyles in a low-income Hispanic population. The content of the program included nutrition information designed to help mothers of preschool children provide for their children's nutritional needs. Previous studies suggest that low-income Hispanics often demonstrate low intakes of vitamins A and C, calcium, iron, and protein, and high rates of diabetes, obesity, and infections. Additionally, this population presents many obstacles for nutrition educators including limited resources, child care, transportation, time, language, culture, literacy, health beliefs, and, in some cases, the transient nature of the population. The program attempted to overcome these barriers by incorporating a flexible program format carried out by abuela (Hispanic grandmother) educators using the processes described in the Stage of Change Model. The program was evaluated using a knowledge, skills and behavior pre-test, post-test, and six-month follow-up survey on both the abuela educators as well as the actual class participants. Results of the peer education training sessions suggest that this type of training program can be effective in increasing the knowledge, skills, and behavior of peer educators as well as reduce need for retraining for educators who continuously teach classes. Additionally, the results suggest that this type of program can be effective in changing selected nutrition related knowledge, skills, and behaviors leading to healthy lifestyles for low-income Hispanic mothers of preschool children.

Adult↗

PubMed2004

Frontal and temporo-parietal lobe contributions to theory of mind: neuropsychological evidence from a false-belief task with reduced language and executive demands.

A model of the functional and anatomical basis of belief reasoning is essential for understanding the relationship between belief reasoning and other cognitive processes in both normal development and pathology. Studies of brain-damaged patients can give valuable insights into the nature of belief processing but pose unique methodological problems. The current study addresses these problems by using a nonlinguistic belief-reasoning task with substantially reduced executive demands. A case series of 12 brain-damaged patients is presented. The belief-reasoning errors of four patients with damage to the prefrontal cortex appeared to arise from these patients' executive function problems. The belief-reasoning errors of three patients with damage to the temporo-parietal junction could not easily be accounted for in this way, raising the possibility that this brain region has a necessary role in representing beliefs, rather than handling the executive demands of belief-reasoning tasks. We discuss the importance of gaining empirical evidence about the scope of ''theory of mind'' impairments, and the important role for neuropsychological studies in this project.

Adult↗

PubMedDate not supplied

Exploratory analysis of the medical record.

Current patient information systems such as SCAMP have the capacity to store not only highly-structured information such as problem codes, drug lists and laboratory values, but also richer, clinically-descriptive information such as comprehensive natural language problem summaries and other textual data that retain the full clinical information used by physicians in managing their patients. The clinical importance, richness, and extensiveness of this information suggest that techniques which allow computers to process textual data may play a helpful role in clinical research. The analysis programs of the SCAMP system have been developed to explore the potential of this approach.

Ambulatory Care Information Systems↗

PubMed2002

Picture naming by children with hearing loss: II. Effect of phonologically related auditory distractors.

Thirty children with hearing loss (HL) and 129 typically developing (TD) children representing comparable ages, vocabulary abilities, or phonology skills named pictures while attempting to ignore auditory distractors. The picture-distractor pairs were constructed to represent phonologically congruent or conflicting onset relations, for example, the picture "duck" with distractors of /[symbol: see text]/or /[symbol: see text]/, respectively. In children with good phoneme discrimination, congruent distractors speeded naming and conflicting distractors slowed naming, relative to a control condition. Effects were similar in HL and TD subgroups. In children with poorer phoneme discrimination, conflicting distractors did not influence naming in the HL subgroup, regardless of discrimination status, and consistently slowed naming only for discriminated contrasts in the TD subgroup. Phonologic representations appear suitably fine-grained in HL children with good auditory perceptual abilities but may be less well specified, more holistic, and/or less auditory-linguistically based in HL children with poorer auditory perceptual abilities. Results are discussed in terms of the heterogeneous nature of phonologic processing in children with HL.

Adolescent↗

PubMed2005

Roles of American Indian grandparents in times of cultural crisis.

This study examined the roles of contemporary American Indian grandparents in the lives of their grandchildren. Structured interviews were conducted with 20 American Indian grandparents. Analysis of interviews followed a sequence of strategies traditionally identified with the process of data reduction and analysis using qualitative methodologies. Participants reported enculturative responsibilities for their grandchildren in regard to traditional tribal values and knowledges such as tribal spirituality and protocol, cooperative interaction, tribal language and appreciation of nature. Methods of enculturation took the form of stories, modeling, direct teaching and playful interaction.

Aged↗

PubMed1997

[Automation of medical literature--and information services].

It is important for clinical practice to be able to find (or retrieve) relevant literature and to keep informed of the state of medical science. The fact that the contents of articles in journals are now accessible via computers is the result of integration of bibliographic techniques, medical knowledge and computer technology. Articles published in some 5000 medical journals can nowadays be retrieved electronically via Medline and Embase together (but medical literature in Dutch is underrepresented). Computerised insertion of publications into Internet dose not make information traceable or accessible, let alone reliable and readable. It cannot be predicted if electronic versions of scientific periodicals will replace the printed editions completely. However, valuable, reliable information will always have its price, even on Internet. It is unlikely that electronic information published privately (internet) will replace scientific publishers soon, for readers will still want selection and monitoring of contents and language. Good layout, professional typography and suitable illustrations to enhance reading comfort and cognitive processes, will even become more important. The problems arising from the immensity of scientific knowledge are not (any longer) of a technological nature-what is needed is a cultural about-turn of the information infrastructure in medical-scientific associations, organizations and institutions.

Computer Communication Networks↗

PubMed2004

The role of discourse context in the processing of a flexible word-order language.

On-line comprehension studies of flexible word-order languages find that noncanonical ('scrambled') structures induce more difficulty than canonical structures [e.g., Hyona & Hujanen, Q. J. Exp. Psychol. 50A (1997) 841-858], with this difference being attributed to the structural complexity/infrequency of these forms. However, by presenting sentences in isolation, most existing studies have not examined the extent to which processing patterns can be explained by discourse factors. In Finnish, an articleless flexible word-order language with canonical SVO order, word order can be used to encode the given/new distinctions: OVS marks the object as given and the subject as new; SVO is more flexible, being used in multiple contexts. Thus, the observed dispreference for noncanonical orders in previous work may arise from additional presuppositions needed to understand them out of context [cf. Crain & Steedman, Natural Language Parsing, (1985), 320-358]. Two experiments were conducted to examine these issues in Finnish. Experiment 1 used a self-paced reading task to show that the usual difficulty associated with noncanonical constructions is partially alleviated in the presence of appropriate discourse contexts. In Experiment 2, the eye gaze of listeners was tracked as they heard spoken descriptions of scenes, so as to test whether specific on-line referential processes are involved in SVO/OVS comprehension: Upon hearing an OV... sequence, Finnish listeners should expect the upcoming noun to be discourse-new, whereas an SV... sequence makes no such prediction. The results confirmed these predictions. As compared to SVO, OVS sentences showed anticipatory eye movements to a discourse-new referent at the second noun onset, even before participants had enough acoustic information to recognize this word. Our findings illustrate that in a flexible word-order language, a noncanonical order can result in anticipatory processes regarding the discourse status of a yet-to-be-heard constituent.

Eye Movements↗

PubMed2005

The speech of reality and the speech of the stage: life, science and art.

Word is the most frequent way of communication in the human experience. As a mean of communication it influences the sentence formulation, which ought to be the autochthonous expression of thoughts. The experience teaches us that it is necessary to be a sovereign master of our own thoughts and of sentiments of others. This is one of the fundamental postulates of the communication in the word category. To speak correctly means to think correctly and that, on the other hand, means in the grammatical, lexical and stylistic aspect to be able to create a sentence as a way of getting across the thoughts, ideas and contents of the spirit. The community mentality, the person's characteristics (the temper, the type and the intensity), the education level, the range of the knowledge and the volume of their potentially creative synthesis determine the lexical richness and the amplitude of the use and the application of the language with the aim of establishing a high quality communication with words as a basic mean of that process. Within this context a word has its impressive and expressive dimensions. Its impressive dimension is created by the common reliance on the frequency of the use of some lexical possibilities and their variations. It is an individual characteristic of the spoken and the written output of every person and it also determines the singularities of a person's style, to that extent that it helps to detect the author of a text with a high percentage of accuracy even in the cases where the author is unknown. The expressive value of a word denotes the author's level of thinking depending on the situation in which he uses the words to express his thoughts. In this sense the word is chosen with a different approach for the communication on a friendly or intimate level from an approach used in a communication on the official level or in a relation between the individual and the public. All this affirms the word as a mean that is individually chosen and used for the expression of the speaker's ideas, attitudes and points of view in the communication process, which reveals the characteristics and the speaker's level in all the named aspects of the word value assessment. In the case of evaluation., of the word through the experience of the on-stage speech, that is, the words in the experience of the theatre art, the approach to the value assessment is contrary to the assessment carried out in an everyday, real experience. In the artistic language the words are already given, the sentences are formulated and all this is determined by the author's will and the act of creation. The actor is the interpreter of the author, his ideas along with the characters of the protagonists and the spirit of the action and, therefore, he must gradually master the word to the extent where it seems spontaneous from the point of view of the impressive and expressive categories. It also has to sound similar to the natural speech and its suggestive influence. With this counter-natural direction of the treatment of the given word it is important to reach the level of spontaneity of the expression to an almost documentary form in the overall verbal-scenic-mimic articulation. In this process the life and the art mesh and the art illustrates and defends the life.

Activities of Daily Living↗

PubMed2002

Receptive and expressive language skills of children with five years of experience using a cochlear implant.

The language of 7 children who had used a cochlear implant for 5 years was evaluated by means of the Clinical Evaluation of Language Fundamentals-3, the Peabody Picture Vocabulary Test-Revised, and the Expressive Vocabulary Subtest of the Test of Word Knowledge. All subjects demonstrated impaired skills relative to normal-hearing children on 1 or more subtests. Variability in performance occurred between subjects and within subjects across subtests. Strengths in semantic skills were evident compared to weaker syntactic and morphological abilities. The nature of the subjects' language impairments is considered with reference to language delay and specific language impairment. The findings support the need for further evaluation of the rate and course of development of language subskills. Investigation of the influences of information processing, and learning styles and strategies, on children's outcomes is also warranted. These findings have implications for implementation of optimal habilitation and education programs for children with cochlear implants.

Child↗

PubMedDate not supplied

Visual and language processing deficits in compensated and uncompensated college students with dyslexia.

In seven experiments, we investigated whether compensated and uncompensated adults with dyslexia show different patterns of deficits in magnocellular visual processing and in language processing tasks. In four visual tasks, we failed to find evidence of magnocellular deficits in either group. However, both groups of adults with dyslexia showed deficits in component language skills, and the degree of reading impairment predicted the nature and extent of these deficits. Uncompensated readers showed deficits in orthographic and especially phonological coding and awareness and were slower on rapid naming. Compensated readers showed word and nonword performance below controls but better than the uncompensated readers. The compensated group was not significantly less accurate than controls on phonological awareness, nor significantly worse overall on rapid naming.

Adolescent↗

PubMed1981

Using the long-term care information system for effective community care.

Obtaining appropriate long-term care is a problem common to individuals in need, community service providers, regulatory agencies, and fiscal intermediaries. The fragmented nature of the long-term care system precludes natural linkages among service programs. The Long-Term Care Information System Assessment Process was developed and demonstrated to be a communication link among programs and agencies concerned with long-term care. The use of its common language tools for decision making and program organization leads to the provision of appropriate long-term care, efficient use of resources, and effective community care.

Health Services Needs and Demand↗

PubMed1979

Critique of concepts and therapy in the action language approach to psychoanalysis.

Critical evaluation is made of the attempts to reformulate basic psychoanalytic concepts in terms of a theory of action language. The criticism focuses on issues of the scientific status of psychoanalytic knowledge, the role of experience as the basis of psychoanalytic knowledge, the role of metaphor in the formulation of psychoanalytic theory (focusing particularly on the issue of anthropomorphism and the forms of acceptable metaphor in the theory), and the problem of levels of abstraction in theoretical conceptualization. Particular issues in the action language approach, which are challenged from a more traditional process-oriented psychoanalytic perspective, are the notion of action; the status of mind; the specific formulations and conceptualizations of drives and motives, conflicts, resistance, affects, and internalization; the nature of the concepts of self and identity. The critique developed in these areas is then utilized as the basis for assessment of clinical implications, particularly their application in specific psychoanalytic contexts.

Affect↗

PubMed2006

The structures of letters and symbols throughout human history are selected to match those found in objects in natural scenes.

Are there empirical regularities in the shapes of letters and other human visual signs, and if so, what are the selection pressures underlying these regularities? To examine this, we determined a wide variety of topologically distinct contour configurations and examined the relative frequency of these configuration types across writing systems, Chinese writing, and nonlinguistic symbols. Our first result is that these three classes of human visual sign possess a similar signature in their configuration distribution, suggesting that there are underlying principles governing the shapes of human visual signs. Second, we provide evidence that the shapes of visual signs are selected to be easily seen at the expense of the motor system. Finally, we provide evidence to support an ecological hypothesis that visual signs have been culturally selected to match the kinds of conglomeration of contours found in natural scenes because that is what we have evolved to be good at visually processing.

Cultural Evolution↗