Search PubMed⌕ Search

Biomedical subjects

L K Obler

Publications and source records attributed to L K Obler.

At least 19 recordsLinked to original sources
PubMed2001

Effect of socioeconomic status on aphasia severity and recovery.

Low levels of educational attainment and low socioeconomic status have been significantly linked to poor health and increased incidence of disease, including Alzheimer's disease and diseases of the cardiovascular, pulmonary, renal, and gastrointestinal systems. Our goal in the present study was to determine the degree to which educational level and socioeconomic status influence initial severity of aphasia and subsequent recovery. We evaluated the records of 39 persons with aphasia twice: at about 4 months and 103 months postonset. We found early severity of aphasia to be significantly greater for subjects in the lower educational and occupational groups. However, rate of recovery (the slope of the recovery curve) was the same regardless of educational or occupational status.

Aphasia↗
PubMed2000

Verbal pragmatics following unilateral stroke: emotional content and valence.

Verbal pragmatic aspects of discourse production were examined in 16 right brain-damaged (RBD), 16 left brain-damaged (LBD), and 16 normal control right-handed adults. The facilitation effect of emotional content, valence hypothesis, and relationship between pragmatics and emotion were evaluated. Participants produced monologues while recollecting emotional and nonemotional experiences. Transcribed monologues were rated for appropriateness on 6 pragmatic features: conciseness, lexical selection, quantity, relevancy, specificity, and topic maintenance. Overall, brain-damaged groups were rated as significantly less appropriate than normals. Consistent with the facilitation effect, emotional content enhanced pragmatic performance of LBD aphasic participants yet suppressed performance of RBD participants. Contrary to the valence hypothesis, RBD participants were more impaired for positive emotions and LBD participants for negative emotions. Pragmatic appropriateness was not strongly correlated with a measure of emotional intensity.

Adult↗
PubMed1999

Psychometric aspects of verbal pragmatic ratings.

This study examined the psychometric aspects of a verbal pragmatic rating scale. The scale contained six pragmatic features (i.e., Conciseness, Lexical Selection, Quantity, Relevancy, Specificity, and Topic Maintenance) based on Grice's cooperative principles. Fifteen right brain-damaged (RBD), 15 left brain-damaged (LBD), and 16 healthy normal control (NC) right-handed adult participants produced narratives while recollecting emotional and nonemotional experiences. Naive raters evaluated each pragmatic feature for appropriateness on a 5-point Likert scale. When reliability was examined, the overall internal consistency of the pragmatic scale was extremely high (alpha =.96). Factor analysis was conducted to examine the theoretical relations among the six pragmatic features. Three meaningful factors involving discourse content, conceptual unity, and parsimony were identified. Findings are discussed in light of Grice's model and the construct validity of the scale.

Aged↗
PubMed1999

Verb naming in normal aging.

Few studies have examined verb naming in normal aging, although decline in the ability to name nouns has been well documented. In this study, we examined longitudinal performance on the Action Naming Test (ANT), a confrontation naming test for verbs. The purpose of this study was to confirm the verb naming deficit associated with aging, which was previously seen only in cross-sectional studies, and to provide additional normative data on verb naming ability that may prove useful to studies on verb naming in populations with brain dysfunction. Sixty-six healthy men and women aged 30 to 79 were each tested with the ANT 3 times over a 7-year span. ANT performance showed a significant decline over time for all participants except the youngest group. Longitudinal methodology supports the conclusion that this finding of a decline in verb naming ability arises from true age-related changes and not from cohort differences.

Adult↗
PubMed1999

The effects of age and gender on the perception of lexical emotion.

The primary purpose of this study was to examine the perception of lexical/verbal emotion across the adult life span. Secondary goals were to examine the contribution of gender and valence (i.e., pleasantness/unpleasantness) to the processing of lexical emotional stimuli. Participants were 28 young (ages 20-39), 28 middle-aged (ages 40-59), and 28 older (ages 60-85) right-handed adults; there were 14 men and 14 women in each age group. Age groups were comparable on demographic and cognitive variables. Participants made accuracy judgments and intensity ratings of emotional (both positive and negative) and nonemotional stimuli from lexical perception tasks from the New York Emotion Battery (Borod, Welkowitz, & Obler, 1992). Accuracy and intensity measures were not significantly correlated. When age was examined, older participants perceived emotional and nonemotional lexical stimuli with significantly less accuracy than did younger and middle-aged participants. On the other hand, older participants evaluated the nonemotional lexical stimuli as significantly more intense than younger participants. When gender was examined, lexical stimuli were processed more accurately by female than male participants. Further, emotional stimuli were rated more intense by female participants. Clinical implications of these findings are discussed.

Adult↗
PubMed1999

Emotional versus nonemotional lexical perception in patients with right and left brain damage.

OBJECTIVE: This study examined lexical emotional perception in patients with unilateral brain damage. BACKGROUND: Hypotheses pertaining to laterality and emotion were tested. More specifically, we were interested in whether the right hemisphere is dominant for verbally-presented emotion. In addition, we examined whether emotional content improves the performance of patients with left brain damage (LBD) and language deficits. METHOD: Subjects were 11 patients with right brain damage (RBD), 10 patients with LBD, and 15 normal control adults. The subject groups did not differ significantly on demographic or basic cognitive variables; the patient groups were similar on neurologic variables. Parallel emotional experimental and nonemotional control tasks included word identification (or recognition), sentence identification, and word discrimination. There were eight emotional categories (e.g., happiness) and eight nonemotional categories (e.g., vision). RESULTS: A significant interaction among Group, Condition, and Task revealed that patients with RBD were significantly impaired relative to patients with LBD and normals within the emotional condition, particularly for the identification tasks. Furthermore, the performance of patients with LBD and language deficits was improved by emotional content for the sentence identification task. CONCLUSIONS: These findings suggest that the right hemisphere has a unique contribution in the identification of lexical emotional stimuli. Implications for rehabilitation of patients with LBD and language deficits and patients with RBD by means of emotion-based strategies are discussed.

Adult↗
PubMed1998

Right hemisphere emotional perception: evidence across multiple channels.

Emotional perception was examined in stroke patients across 3 communication channels: facial, prosodic, and lexical. Hemispheric specialization for emotion was tested via right-hemisphere (RH) and valence hypotheses, and relationships among channels were determined. Participants were 11 right-brain-damaged (RBD), 10 left-brain-damaged (LBD), and 15 demographically matched normal control (NC) adults. Experimental measures, with analogous psychometric properties, were identification and discrimination tasks, including a range of positive and negative emotions. Nonemotional control tasks were used for each channel. For identification, RBDs were significantly impaired relative to LBDs and NCs across channels and valences, supporting the RH hypothesis. No group differences emerged for discrimination. Findings were not influenced by demographic, clinical, or control variables. Correlations among the channels were more prominent for normal than for brain-damaged groups.

Adult↗
PubMed1997

Dual processing of open- and closed-class words.

A series of articles in the past two decades has suggested differential processing of open- and closed-class lexical items by normal adults. Difficulties in replicating a crucial study (Bradley, 1978), however, have weakened the dual route hypothesis. We matched 16 French open-class items to 16 closed-class items for phonological structure, world length, and relative word frequency. Three agrammatic aphasics revealed strikingly more phonological errors on closed-class than open-class items. Dysfluencies were greater on closed-class items and contributed to greater overall reading time for the closed-class words, consistent with a two-route model for the production of closed- and open-class lexical items in Broca's aphasics and, thus, normals.

Aged↗
PubMed1996

On the nature of naming errors in aging and dementia: a study of semantic relatedness.

This study investigated the nature of naming errors produced on the Boston Naming Test by patients with mild and moderate Alzheimer's disease (AD) and elderly and young controls, using a newly devised scoring system. This new approach involved ratings of error responses on a scale of semantic relatedness to the target name. Error responses of both mild and moderate AD subjects were no less semantically related to target names than were responses of age- and education-matched controls. We conclude that some available evidence of semantic loss in AD may be an artifact of the methodology chosen for evaluating naming errors.

Adult↗
PubMed1996

Hemispheric specialization for discourse reports of emotional experiences: relationships to demographic, neurological, and perceptual variables.

This study examined hemispheric specialization for discourse reports of emotional and nonemotional experience in 16 right-brain-damaged (RBD), 16 left-brain-damaged (LBD), and 16 demographically-matched normal control (NC) right-handed adults. Patient groups did not differ on etiology, months post-CVA onset, and intrahemispheric lesion location. Subjects were requested to produce monologues about positive and negative emotional and nonemotional experiences. The lexical content of written transcriptions of these monologues was later rated for "emotionality" by naive judges. Overall, RBDs described experiences with less emotional intensity than did NCs and LBDs, providing support for right hemisphere involvement in lexical emotion. Although the RBDs in the current study demonstrated similar patterns of deficits in a prior study [9] on tasks involving lexical emotional perception, there were no significant relationships between the current measures of emotional expression and the previous measures of emotional perception. Finally, the expression and the perception data were examined with respect to intrahemispheric factors. Among the brain-damaged subjects, subcortical structures were more involved in reports of emotional experience, and cortical structures were more involved in the perception of emotion.

Age Factors↗
PubMed1996

Left and right hemispheric contributions to discourse coherence and cohesion.

Linguistic coherence and cohesion were examined in patients with unilateral left brain damage (LBD), unilateral right brain damage (RBD), and normal control (NC) right-handed adults. Groups were matched for age, gender, occupation, and education. Brain-damaged groups did not differ for months post onset or intrahemispheric lesion site. Contrary to previous literature, results indicated that LBDs, all of whom were aphasic, demonstrated impairments in coherence but not cohesion, relative to NCs and RBDs. Surprisingly, among RBDs, overall coherence and cohesion were spared. When the relationship between measures of coherence and cohesion was examined, there were few significant correlations and no systematic patterns. Results support the notion that coherence and cohesion represent coexisting and independent linguistic systems. Further, the findings suggest that descriptions of discourse integrity need to account for the perspective of both the speaker and listener.

Aged↗
PubMed1995

Variability in aphasia research: aphasia subject selection in group studies.

Subject selection criteria and descriptive data were compiled from 15 consecutive aphasia group studies published in Brain and Language from its inception (1974-1976) and two decades later. While some measures remain constant (aphasia type and lesion site are most commonly used in both periods), additional measures are reported only or more frequently in the recent period (e.g., age, handedness, bilingualism, language spoken, multiple vs. single lesions). Of interest is the decrease in the total number of subjects included in aphasia group studies from the early to the current period.

Aphasia↗
PubMed1994

Wernicke and Alzheimer on the language disturbances of dementia and aphasia.

Signs of language dysfunction in dementia of the Alzheimer's type (DAT) and in the aphasic syndromes of transcortical sensory aphasia and Wernicke's aphasia are superficially similar. The unresolved question concerning the extent to which the language disturbances of DAT are "aphasic" is linked to a more fundamental question concerning the relation of language to thought, given that aphasia is often defined as language disturbance without disturbance of intellect, and dementia as dissolution of intellectual function, of which language forms an integral part. In this paper we explore the historical roots of today's debate by analyzing the original case studies of Wernicke (1874) and Alzheimer (1907, 1911). Although each of these neurologists described similar patterns of language disturbance, they drew different conclusions. Wernicke argued for a distinction between language and thought and between the language disturbances of aphasia and those of dementia. Alzheimer continued the then dominant paradigm of aphasia in describing the language disturbances of his demented patients as aphasic. Paradoxically his conclusion makes him appear, in contrast to Wernicke, to argue for the identity of the language disturbances of aphasia and dementia. Yet he himself acknowledged that the presence of focal language symptoms arising from diffuse degenerative pathology was indeed problematic. We conclude that today's discussion could profitably be refocused on the question which emerges from the original works of Wernicke and Alzheimer, which Alzheimer himself asked, and which remains unanswered: How can diffuse cerebral pathology give rise to a pattern of language deficit virtually identical to that of a focal lesion?

Aged↗
PubMed1994

Special talents in Geschwind's and Galaburda's theory of cerebral lateralization: an examination in a female population.

Geschwind and Galaburda (1985) proposed that delayed growth of posterior left hemisphere sites in male dyslexics are associated with markers of anomalous dominance (AD) and special cognitive talents. We found that talent in a female population was related to the strength of nonright-handedness, and was elevated in right-handed individuals with histories of familial left-handedness. Subjects reporting a history of dyslexia tended to be musically talented. While immune disorders were not related to talent for the whole population, they did co-occur with talents in a group of 10 individuals reporting 7 or more AD markers.

Adult↗
PubMed1993

Suppression and facilitation of pragmatic performance: effects of emotional content on discourse following right and left brain damage.

This study examines the effect of emotional content on the verbal pragmatic aspects of discourse production in right-brain-damaged (RBD), left-brain-damaged (LBD), and normal control (NC) right-handed adults. Subject groups were matched for gender, age, education, and occupation; brain-damaged groups did not differ on months post CVA onset and lesion location. Subjects were screened to ensure that they demonstrated adequate cognitive and visual perceptual skills to participate in the study. Pictorial stimuli were used to elicit discourse that contained emotional and nonemotional (procedural, visuospatial) content. Trained raters evaluated each discourse for appropriateness on seven verbal pragmatic features (e.g., conciseness, quantity, relevancy). Across all three conditions, the brain-damaged groups were impaired relative to NCs. In the nonemotional conditions, LBDs were particularly impaired in pragmatics, whereas in the emotional condition, RBDs demonstrated pragmatic deficits. Emotional content appeared to facilitate pragmatic performance among LBD aphasics and to suppress pragmatic performance among RBDs.

Aphasia↗
PubMed1992

Right hemisphere specialization for the identification of emotional words and sentences: evidence from stroke patients.

This study examines the contribution of the lexical/verbal channel to emotional processing in 16 right brain-damaged (RBD), 16 left brain-damaged (LBD) and 16 normal control (NC) right-handed adults. Emotional lexical perception tasks were developed; analogous nonemotional tasks were created to control for cognitive and linguistic factors. The three subject groups were matched for gender, age and education. The brain-damaged groups were similar with respect to cerebrovascular etiology, months post-onset, sensory-motor status and lesion location. Parallel emotional and nonemotional tasks included word identification, sentence identification and word discrimination. For both word tasks, RBDs were significantly more impaired than LBDs and NCs in the emotional condition. For all three tasks, RBDs showed a significantly greater performance discrepancy between emotional and nonemotional conditions than did LBDs or NCs. Results were not affected by the valence (i.e. positive/negative) of the stimuli. These findings suggest a dominant role for the right hemisphere in the perception of lexically-based emotional stimuli.

Aged↗