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Biomedical subjects

J Rönnberg

Publications and source records attributed to J Rönnberg.

At least 19 recordsLinked to original sources

Signed and spoken language perception studied by positron emission tomography.

Sign and spoken language seem to be localized in the same brain areas. They elicit similar regional cerebral blood flow (rCBF) patterns, even though sign language is dependent on spatial information. We investigated sign and spoken language perception in a group of healthy bilingual subjects. Four videotaped activation conditions were used during PET imaging: (1) sign language, (2) spoken language, (3) spoken language with mouth covered, and (4) spoken language on a sound track while showing a motionless face. Spoken language (condition 4) activated significantly the perisylvian cortex (Brodmann areas 22 and 43) bilaterally. Sign language activated the visual association areas (Brodmann areas 37 and 19) but did not selectively activate parietal regions. A reciprocal relationship was observed between the level of activation in visual language perception areas and that in auditory perception areas. We conclude that when healthy bilingual subjects use the visual route for sign language perception, the functional anatomy overlaps that of language processing containing both auditory and visual components.

Adult

Memory dysfunction in mild aphasics.

The effect of mild aphasia (n = 9), as a result of subarachnoid haemorrhage (SAH), was evaluated against one matched (sex, age, and education) control group suffering from SAH of unknown origin without aphasia, and against one matched healthy control group. According to aphasia testing (Reinvang & Engvik, 1980), criteria for a classical diagnosis were not met. Therefore, the patients were characterized as mild aphasics: They generally displayed intact audo-verbal comprehension and repetition abilities, and they demonstrated a fluent, spontaneous speech. However, they showed phonemic and semantic paraphasias, with self-corrections; a few patients displayed alexia and agraphia. Memory performance of these three groups was evaluated by a neuropsychological test battery, designed to tap various components of verbal memory function. From the results it was concluded that: (a) Short-term memory is impaired, as regards the phonological loop and the central executive in working memory, whereas maintenance rehearsal is unaffected, given that the demands on phonological coding is minimized, (b) long-term memory is also generally impaired, whereas long-term learning and forgetting by means of subject-performed tasks proceeds within a normal range. Impairments were hypothesized to reflect less efficient central executive functions of working memory, involving generation of less appropriate semantic codes and phonological representations, (c) mildly aphasic patients are not subjectively aware of their own memory deficits, and (d) aphasia classification by means of standard procedures do not sufficiently characterize the nature of a mildy aphasic patient's memory problems.

Adult

Speech gestures and facial expression in speechreading.

Two experiments investigated the role of facial expression in speechreading. In Experiment 1 sentences were presented either with only the actor's face shown or with the actor shown in half-size. One happy script with happy, sad and neutral sentences was used, and either a content cue or an emotional cue was presented prior to each sentence. In Experiment 2 happy and sad sentences from one happy and one sad script were first recorded by the actor with a neutral face (face and shoulder shown) and then with a congruent facial expression. The results revealed that there was no difference in performance between half-size and face presentation, but content cues increased performance compared to emotional cues. As expected (Abelson, 1981), happy sentences were easier to speechread than sad in the happy script and vice versa. Also, facial expression raised performance for happy sentences in the happy script. Positive emotions are suggested to be associated with approach behavior in part relying on increased non-pantomimic speech gestures and articulation of the speaker (e.g., Davidson et al., 1990).

Adult

Facial expressions and speechreading performance.

In the present study, the role of facial expressions in visual speechreading (lipreading) was examined. Speechreading was assessed by three different tests: sentence-based speechreading, word-decoding, and word discrimination. Twenty-seven individuals participated as subjects in the study. The results revealed that no general improvement as a function of expression was obtained across all tests. Nevertheless, skilled speechreaders could significantly improve their performance as a function of emotional expression in the word-decoding and word-discrimination conditions. Furthermore, a correlational analysis indicated that there was a significant relationship between the subjects' rating of confidence regarding their responses to each test-item and performance on speechreading tests where lexical analysis is a necessary task-demand. The results are discussed with respect to how information from facial expressions is integrated with the information given by the lip movements in visual speechreading, and also with respect to general models of face-processing (i.e., Bruce & Young, 1986; Young & Bruce, 1991).

Adult

Lipreading with auditory low-frequency information. Contextual constraints.

The present experimental study investigated potential relations among three variables: (1) an audiovisual speech signal (i.e., low-frequency supplemented lipreading as opposed to pure lipreading), (2) typical, as opposed to atypical, sentences in a particular script (e.g., in a restaurant), and (3) the presence/absence of additional context (in the particular script) in 60 normal hearing subjects. All three variables revealed significant main effects, but no interactions were observed. The general facilitatory effect for the audiovisual signal is in line with previous research, but this effect was relatively weak compared to the main effect of typicality, which relies on cognitive activation of scripts. In a separate analysis, the typicality variable was also the only variable that interacted significantly with speechreading skill, typical sentences being perceived relatively easier by the skilled as opposed to the less skilled individual. The clinical implications of cognitive factors in hearing-aid fitting procedures, the construction of speech materials, and selection of individuals for rehabilitation were discussed.

Humans

Audio-visual speechreading in a group of hearing aid users. The effects of onset age, handicap age, and degree of hearing loss.

Speechreading ability was investigated among hearing aid users with different time of onset and different degree of hearing loss. Audio-visual and visual-only performance were assessed. One group of subjects had been hearing-impaired for a large part of their lives, and the impairments appeared early in life. The other group of subjects had been impaired for a fewer number of years, and the impairments appeared later in life. Differences between the groups were obtained. There was no significant difference on the audio-visual test between the groups in spite of the fact that the early onset group scored very poorly auditorily. However, the early-onset group performed significantly better on the visual test. It was concluded that the visual information constituted the dominant coding strategy for the early onset group. An interpretation chiefly in terms of early onset may be the most appropriate, since dB loss variations as such are not related to speechreading skill.

Age Factors

The role of emotionality and typicality in speechreading.

Two experiments were carried out to investigate how emotionality and typicality could influence speechreading performance. Typical and atypical sentences for a certain script, and emotional sentences (happy and sad content, presented with happy, sad or neutral facial expression) were shown without sound on a TV-screen. Two different scripts (restaurant and doctor) were used. In Experiment 1, hearing-impaired subjects participated and in Experiment 2, normal-hearing subjects participated. Experiment 2 also evaluated the effects of tactile information. The results from both experiments showed that typical restaurant sentences were the easiest to speechread of all sentence-types, in line with script-theory (Abelson, 1981; Anderson, 1983; Bellezza & Bower, 1981; Nottenburg & Shoben, 1980; Yekovich & Walker, 1986). For the doctor script, sad sentences were better speechread than happy sentences, also according to script-theory. In addition, perception of emotional content was enhanced by tactile information. Generally, both the cognitive and emotional effects are script-dependent, suggesting important social constraints on speechreading accuracy.

Adult

RASP: a system for the analysis of memory tasks.

The purpose of this paper is to introduce a system for the analysis of memory tasks. The system involves four basic task dimensions, derived from an ecological analysis of memory functioning: Reproductivity (R), Acquisition (A), Sufficiency (S), and Productivity (P). Three studies are reported in which professional memory psychologists were asked to rate sets of standard laboratory and more ecologically relevant memory tasks in terms of the four RASP dimensions. In general, results implied independence across the two sets of tasks between the four dimensions. Interrater reliabilities were found to be modest to high. However, it was suggested that RASP best be used as a tool for understanding the meaningful relations that exist among dimensions within general sets or pools of tasks, for different classes of tasks, as well as for prototypical tasks. We argue that, especially when the relationship between RASP profiles for two particular tasks is crossvalidated by behavioral data, and conflict with assumptions about what memory systems or processes are involved, then there is a potential for conceptual refinement. This refinement could be attained either through an increased theoretical generalization, or through an increased theoretical precision. Based on obtained RASP information at the level of classes of tasks (e.g., episodic vs. semantic) as well as at a prototypical task level (e.g., word recall vs. prose recall), several intriguing memory phenomena are discussed. Finally, we suggest that RASP may serve as a tool for reducing the number of task-specific assumptions of what systems and processes mediate memory performance.

Humans

CT assessment of subarachnoid haemorrhage. A comparison between different CT methods of grading subarachnoid haemorrhage.

A number of different CT classifications of subarachnoid haemorrhage (SAH) were applied to a consecutive series of 50 patients with aneurysmal SAH. The best correlation with delayed ischaemic deficits (DID) was obtained with a score formed by the sum of the individual cisternal grades except that of the cortical subarachnoid space. The findings emphasize the significance of the extent of the SAH, rather than the presence of a localized cisternal clot with regard to the development of DID.

Aneurysm, Ruptured

Regional cerebral blood flow in sign language users.

Cerebral activation was compared during sign and spoken language comprehension. Nine hearing children of deaf parents were studied and the cerebral activation was measured by recordings of the regional cerebral blood flow. Comprehension of a complex material gave a bilateral activation of posterior temporal regions for both spoken and signed language. It seems that sign language activates the cortex in a way which is very similar to spoken language, when the listener watches the speaker. Cortical areas usually regarded to be important for spatial ability do not show enhanced activation during sign language perception.

Adult

Prediction accuracy of text recall: ease, effort and familiarity.

Prediction accuracy of text recall was studied in two experiments. Text characteristics (i.e., consistency and distinctiveness) were manipulated in Experiment 1, and familiarity with the reading-task in Experiment 2. The results were also analyzed and discussed in terms of easy processing (Experiment 1), and in terms of increased and more active processing (Experiment 2). Text characteristics did not affect prediction accuracy. However, being familiar with the reading-task led to good and long-lasting prediction accuracy. Thus, subjects reading a school-book text, instructed to learn the contents of it demonstrated reliable memory awareness, both for immediate recall and for delay of one week. It was also suggested that increased processing demands and active reading enhances prediction accuracy.

Achievement

Subarachnoid blood on CT and memory dysfunctions in aneurysmal subarachnoid hemorrhage.

Ninety patients with a previous subarachnoid haemorrhage (SAH) were given a set of memory tests comprising immediate free recall of words (indexing long-term memory, LTM, and short-term memory, STM), final free recall of words (indexing LTM), final cued recall of words (indexing LTM), and a digit span test (indexing working memory, WM). Patients with a large amount of blood on CT, carried out within 72 h of the bleed, showed LTM as well as STM dysfunction, whereas patients with a small amount of subarachnoid blood evidenced only STM dysfunction. Patients with the ruptured aneurysm located on the anterior cerebral artery, however, constituted an exception with dysfunction of both LTM and STM together with intact WM, independent of the amount of subarachnoid blood. Also, patients with internal carotid artery or middle cerebral artery aneurysms and large volume SAH displayed LTM dysfunction, but differed concerning STM, the former showing intact STM and the latter showing STM dysfunction. Thus, it appears, that the combined information from factors such as the amount of subarachnoid blood and the location of the ruptured aneurysm is of vital importance for explaining the different patterns of memory dysfunctions after SAH.

Adult

Internal speech functioning and speechreading in deafened and normal hearing adults.

The present study compared internal speech functioning in two groups of subjects: deafened and normal hearing adults. Internal speech functioning was assessed by means of either direct testing (i.e. rhyme-judgement tasks) or indirect testing (lexical access tests). No differences between the groups across tasks was obtained for speed. Neither was there any difference in accuracy level assessed by indirect tests. For direct testing the deafened group performed at a significantly lower level of accuracy. Accuracy was also correlated with the number of years that they had been deaf. It was concluded that one of the primary consequences of an acquired deafness is that the representational aspects of internal speech deteriorate over time, whereas the mechanical aspects remain relatively intact. Intercorrelations between accuracy level in direct testing and speechreading performance also suggest that speechreading ability declines. Clinical implications of the results are discussed.

Deafness

The effects of background noise and working memory capacity on speechreading performance.

The present study was conducted to investigate the effects of background noise and working memory capacity on speechreading performance. The results displayed no differences in speechreading performance (i.e. on a word-test and on a sentence-test) due to background noise. When working memory capacity was correlated with speechreading, only one of the two tests of working memory capacity (i.e. the reading span task) was found to be related to speechreading performance. This relationship applies to both speechreading tests, but only to one specific background noise condition in the tests: meaningful noise. The results are discussed with respect to the demands of simultaneous storage and processing in working memory and how these demands apply to speech-based noise distractors. It was also concluded that although performance was similar across different background noise conditions, they apparently engage different components of the individual's cognitive system.

Adult

Vibrotactile support: initial effects on visual speech perception.

The study investigated the initial effects of the implementation of vibrotactile support on the individual's speech perception ability. Thirty-two subjects participated in the study; 16 with an acquired deafness and 16 with normal hearing. At a general level, the results indicated no immediate and direct improvement as a function of the implementation across all speech perception tests. However, when the subjects were divided into Skilled and Less Skilled groups, based on their performance in the visual condition of each test, it was found that the performance of the Skilled subjects deteriorated while that of the Less Skilled subjects improved when tactile information was provided in two conditions (word-discrimination and word-decoding conditions). It was concluded that tactile information interferes with Skilled subjects' automaticity of these functions. Furthermore, intercorrelations between discrimination and decoding tasks suggest that there are similarities between visually and tactilely supported speechreading in how they relate to sentence-based speechreading. Clinical implications of the results were discussed.

Adult

Memory effects following carbamazepine monotherapy in patients with complex partial epilepsy.

To evaluate the memory effects of carbamazepine (CBZ) monotherapy, a relatively large computerized neuropsychological test battery, specially developed to assess the properties of different memory systems, was administered to a group of patients with epilepsy in a pre-test--post-test control group design. Consistent with previous findings, the results show that CBZ treatment does not induce any general important or consistent negative signs of memory dysfunction. However, the epilepsy group as such demonstrates a relative inability to carry out more complex working memory tasks and they are also slower in simple long-term memory access tasks. Finally, the detailed findings suggest that CBZ plasma concentration levels within the therapeutic range are highly and negatively associated with short-term recency, which is a novel finding.

Adult

Normal-hearing and hearing-impaired subjects' ability to just follow conversation in competing speech, reversed speech, and noise backgrounds.

The performance on a conversation-following task by 24 hearing-impaired persons was compared with that of 24 matched controls with normal hearing in the presence of three background noises: (a) speech-spectrum random noise, (b) a male voice, and (c) the male voice played in reverse. The subjects' task was to readjust the sound level of a female voice (signal), every time the signal voice was attenuated, to the subjective level at which it was just possible to understand what was being said. To assess the benefit of lipreading, half of the material was presented audiovisually and half auditorily only. It was predicted that background speech would have a greater masking effect than reversed speech, which would in turn have a lesser masking effect than random noise. It was predicted that hearing-impaired subjects would perform more poorly than the normal-hearing controls in a background of speech. The influence of lipreading was expected to be constant across groups and conditions. The results showed that the hearing-impaired subjects were equally affected by the three background noises and that normal-hearing persons were less affected by the background speech than by noise. The performance of the normal-hearing persons was superior to that of the hearing-impaired subjects. The prediction about lipreading was confirmed. The results were explained in terms of the reduced temporal resolution by the hearing-impaired subjects.

Audiometry

Purposive behaviour in cognition and perception: considerations of awareness in memory.

The responses to the original article by Rönnberg (1990a) provoked interesting and thoughtful points of view that are covered by Gärling (1990), Hjelmquist (1990), Montgomery (1991), and Runeson (1990). These articles do not merely present a different outlook but also provide concepts that are certainly worthy of consideration and add more substance to the general topic under discussion. The purpose of this commentary is to seek an understanding of the ideas presented by the above authors within a synthesis of our views of current conceptualizations in cognition and perception. Each of the original criteria (Rönnberg, 1990a) will be treated in turn.

Animals