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[Diagnostic testing methods for skill assessment in reading, writing, and arithmetic. A critical review].

OBJECTIVES: The diagnosis of a specific developmental disorder of reading, writing and arithmetic can be made based upon individually applied standardized methods for testing scholastic achievement and IQ. To make the choice of suitable methods easier for the administrator of the test, a critical survey of German-language methods for assessing skills in reading, writing and arithmetic is presented. METHODS: Test intention and psychometric properties for scholastic achievement are summarized. The methods are assessed with regard to their utility in the diagnosis of congenital alexia and dyscalculia. Supplementary suggestions for clinical assessment are given. RESULTS: In summary, beyond the primary school area there is a lack of current standardized methods that meet the current standards of quality. Particularly the assessment of arithmetic skills above those of the 4th grade level require resorting to methods of dubious curricular validity. Coverage is once again better for the upper elementary and middle school levels. CONCLUSIONS: There is a need for new constructions, respectively a need to update published scholastic achievement tests.

Adolescent↗

Comparison of reading and spelling in patients with probable Alzheimer's disease.

Patients with probable Alzheimer's disease (AD) are reported to show mild, but reliable, difficulties reading aloud and spelling to dictation exception words, which have unusual or unpredictable correspondence between their spelling and pronunciation (e.g., touch). To understand the cognitive dysfunction responsible for these impairments, 21 patients and 27 age-and education-matched controls completed specially designed tests of single-word oral reading and spelling to dictation. AD patients performed slightly below controls on all tasks and showed mildly exaggerated regularity effects (i.e., the difference in response accuracy between words with regular spellings minus exception words) in reading and spelling. Qualitative analyses, however, did not demonstrate response patterns consistent with impairment in central lexical orthographic processing. The authors conclude that the mild alexia and agraphia in AD reflect semantic deficits and nonlinguistic impairments rather than a specific disturbance in lexical orthographic processing.

Aged↗

Reading problems in chronic aphasia.

Thirty-five aphasic subjects who were 1 year or longer post onset of brain injury were given a battery of reading tests which was composed of recognition and oral reading tests for letters, words, sentences, and paragraphs, and comprehension tests for sentences and paragraphs. Results indicated a residual reading disorder or alexia in all subjects, with comprehension tests producing the highest error rate, oral reading tests second, and then recognition tests. Reading ability was found to be related to overall language skill, level of education, and oral reading ability. Results are discussed in light of current theories of reading and future research needs.

Aphasia↗

Visual syndromes as the presenting feature of degenerative brain disease.

The symptoms of a degenerative brain disease are dictated by its topography. Visuo-spatial impairment may be a severe and early feature of degenerative dementia. Visual symptoms in such patients are broadly divisible into dorsal and ventral visual syndromes, which result from a degenerative focus in occipito-parietal and occipito-temporal visual association cortices, respectively. The dorsal visual syndrome includes asimultanagnosia and Balint's syndrome. The ventral visual syndrome includes alexia and visual agnosia (prosopagnosia). Less often, hemineglect or visual field defects result. When Alzheimer's disease and Creutzfeldt-Jakob disease present in this way there is a topographic shift of neurodegenerative changes to posteriorly situated cortices. Patients with corticobasal ganglionic degeneration often develop symptomatic involvement of contiguous sensorimotor cortices causing mixed perceptual-motor syndromes. Even in patients with more typical patterns of dementia, the degree of visuo-spatial impairment may hinder driving skills, and the issue of driving should be addressed early in the clinical course.

Cerebral Cortex↗

[Current status of aphasia therapy].

Aphasia therapy in adults has been established to a larger extent relatively lately in the history of aphasiology, i.e. after its social medical importance had been realized and one of the cardinal problems of neurology solved more satisfactorily--lesion localization by imaging techniques. In order to evaluate the efficiency of aphasia therapy--which is still not quite uncontradicted--it was necessary to acquire sufficient knowledge of the spontaneous recovery process. It takes place--e.g. after stroke--mainly during the first 3 months, coming, as a rule, to a halt during the first year. Longer recovery periods, however, have been described. Next to etiology neurological status, overall health condition, type and severity of aphasia, and time delay between onset of the disease and start of therapy have been ascertained, whereas age and handedness seem to be of minor relevance. If syndrome change occurs the boundary between Broca's and Wernicke's aphasia is not surpassed; this taken apart almost any change from a more severe to a milder form of aphasia is possible. To isolate the therapeutic effect from spontaneous recovery in larger groups is difficult. There are, however, more recent investigations which suggest, that a correctly indicated therapy, which is sufficiently intensive and lasts long enough, will be effective. One of the corner-stones of any therapeutic effort ist adequate stimulation, oriented toward the patients needs and his aphasic syndrome, and taking into account the systemic nature of language and its most important linguistic structural components. Furthermore, a phase-specific and interdisciplinary approach and integration of closely related persons play an important role. We divide the numerous therapeutic techniques into 3 groups: direct or stimulation approach, indirect or circumventory approach, compensatory or alternative strategies approach. Representatives of all 3 groups are presented briefly, e.g. auditory stimulation, divergent semantic intervention, promoting aphasics communicative effectiveness, language enrichment therapy, programmed instruction; then the deblocking method, melodic intonation therapy, imagery, a sample of linguistically oriented methods for the reeducation of syntax, semantics, and phonemics along with special methods for the treatment of alexia and agraphia; finally compensatory techniques like visual communication, visual action therapy, and bliss symbolics. Some particular problems encountered in working with aphasics are addressed. A point is made about the feasibility and profit of lay therapy.(ABSTRACT TRUNCATED AT 400 WORDS)

Agraphia↗

[Posterior cortical atrophy--a new dementia syndrome or a form of Alzheimer's disease?].

Posterior Cortical Atrophy (PCA) is a neurodegenerative disorder initially dominated by disturbances in higher visual functions including object agnosia, prosopagnosia, alexia, environmental agnosia and Balint's syndrome. Language, memory, insight, and judgement remain relatively preserved until late in the course. A characteristic neuroradiological finding consists of focal bilateral parieto-occipital atrophy demonstrated on MRI and CT. It was speculated that the possible underlying pathologic condition could be an atypical clinical variant of Alzheimer's disease, a lobar atrophy analogous to Pick's disease, a variant of Creutzfeldt-Jakob disease or some previously unrecognized entity. The prognostic question whether the visual agnostic symptoms are only a precursor of generalized dementia remained unsolved. The neuropsychological symptoms in these patients indicate that the occipitoparietal cortex is bilaterally affected which is in contrast to the parietotemporal distribution of lesions in Alzheimer's disease and the frontotemporal type of distribution in Pick's disease. The aim of this study was to review and analyze all cases of posterior cortical atrophy which have been reported in the literature. Up to now 58 cases of posterior cortical atrophy have been described. The first report of such a patient was given by A. Pick in 1902. The results of our analysis show that posterior cortical atrophy is mainly a presenile disorder which in most cases heralds the development of generalized dementia. The histopathological results suggest that the combination of clinical findings referred to as PCA can result from strikingly different pathological entities. However, most cases of PCA which were investigated postmortem revealed the histopathological lesion type of Alzheimer's disease. This suggests that PCA is rather a subgroup of Alzheimer's disease than an independent disease. This conclusion has some implication for the nosological classification of other localized slowly progressive syndromes such as slowly progressive aphasia. These syndromes may as well define possible clinical subgroups of the "classical" dementias. They show that the close relationship between the clinical profile and the brain regions involved does not necessarily imply a specific neuropathological process but focus the attention on the selective vulnerability of distinct neuronal systems.

Adult↗

Consciousness of perception after brain damage.

Disturbances of visual perception after brain damage provide clues to understanding consciousness and the brain. In this article we review six visual disorders in which perception and consciousness are dissociated as a result of brain damage: blindsight, implicit shape perception in apperceptive visual agnosia, covert recognition of faces in prosopagnosia, unconscious perception in neglect and extinction, implicit reading in pure alexia, and implicit object recognition in associative visual agnosia. We consider these six disorders from the standpoint of three main schools of thought concerning consciousness and the brain, namely a localized system for consciousness, consciousness as a state of integration, and consciousness as a property of graded representation. The findings suggest that these syndromes do not share a single mechanism and that it is conceivable that more than one explanation will be necessary both within and across syndromes. We conclude on the basis of the current evidence that it is unlikely that any single brain system is necessary for conscious awareness of perception that does not play a role in perception as well.

Agnosia↗

[Homonymous hemianopsia].

Anatomical principles of the suprachiasmatic pathway. The neuro-ophthalmological examination of homonymous hemianopia: qualitative perimetry (confrontation tests), quantitative perimetry (campimetry on the Bjerrum screen, kinetic perimetry, static perimetry, automatic computer controlled perimetry, perimetry with colours, flickerfusion frequency-perimetry), oculomotor disturbances (gaze strategies, opto-kinetic nystagmus), pupillary disturbances, visual evoked potentials, anosognosia, Riddoch-phenomenom, hemiachromatopsia. Synopsis of different forms of homonymous hemianopsia: Unilateral, total or quadrant, bilateral, temporal half moon preserved or not, homonymous scotomas, horizontal hemianopsia. Pathogenetic analysis: tumors, infarcts, cerebral injuries, neuro-surgical operations, inflammatory conditions, congenital or perinatal brain damages, migraine. Additional disturbances of visual space recognition (hemineglect), of colour vision and of reading ability (alexia). In connection with the above mentioned theme appreciation of the scientific work of Prof. E. Aulhorn (Tübingen) regarding the perimeter apparatus, the perimetric examination technique and the interpretation of the perimetric results.

Brain Mapping↗

Functional organization of human occipital-callosal fiber tracts.

Diffusion tensor imaging (DTI) and fiber tracking (FT) were used to measure the occipital lobe fiber tracts connecting the two hemispheres in individual human subjects. These tracts are important for normal vision. Also, damage to portions of these tracts is associated with alexia. To assess the reliability of the DTI-FT measurements, occipital-callosal projections were estimated from each subject's left and right hemispheres independently. The left and right estimates converged onto the same positions within the splenium. We further characterized the properties of the estimated occipital-callosal fiber tracts by combining them with functional MRI. We used functional MRI to identify visual field maps in cortex and labeled fibers by the cortical functional response at the fiber endpoint. This labeling reveals a regular organization of the fibers within the splenium. The dorsal visual maps (dorsal V3, V3A, V3B, V7) send projections through a large band in the middle of the splenium, whereas ventral visual maps (ventral V3, V4) send projections through the inferior-anterior corner of the splenium. The agreement between the independent left/right estimates, further supported by previous descriptions of homologous tracts in macaque, validates the DTI-FT methods. However, a principal limitation of these methods is low sensitivity: a large number of fiber tracts that connect homotopic regions of ventral and lateral visual cortex were undetected. We conclude that most of the estimated tracts are real and can be localized with a precision of 1-2 mm, but many tracts are missed because of data and algorithm limitations.

Adult↗

Single-case experimental designs in neuropsychological rehabilitation.

It is becoming accepted that single-case studies can offer important contributions to theoretical aspects of neuropsychology. Such recognition has not been so forthcoming in the field of rehabilitation, where single-case studies can be employed to evaluate neuropsychological treatments. This paper describes behavioural approaches to treatment of the neurologically impaired which include single-case experimental designs that have originated in the field of behavioural psychology. Examples of behaviour programmes for the treatment of apraxia and alexia are provided together with examples of single-case experimental designs used to evaluate memory therapy. The paper concludes with a brief discussion of the role of statistics in single-case studies.

Adult↗

A case of associative visual agnosia: neuropsychological findings and theoretical considerations.

A 61-year-old right-handed man fell downstairs and was found unconscious. There was no abnormality in the general physical examinations. Neurological examinations revealed a quadrantanopia. Neuropsychological examination revealed an impairment in recent verbal memory, alexia, agraphia, object agnosia, color naming difficulty, prosopagnosia, and visuospatial constructional disability. CT scan demonstrated subcortical hematomas in the temporo-occipital regions of both hemispheres. MRI demonstrated extensive low-intensity lesions in the lingual, fusiform and posterior inferior temporal gyri on both hemispheres. Both inferior longitudinal fasciculi were also affected. His neuropsychological deficits seem best described as a typical form of associative visual agnosia. From the results of neuroradiological findings, the authors emphasize that associative visual agnosia might be produced by an intrahemispheric disconnection between the visual cortices and the temporal lobes which are supposed to be the storage site of the engrams of visual memories. Moreover, the neuropsychological findings suggest that the visuo-constructional ability to convert the two-dimensional input to the three-dimensional construction and the capacity of three-dimensional imagination were severely impaired in our patient. It was considered that these neuropsychological features play an important role in the recognition difficulties of associative visual agnosia.

Agnosia↗

Selective reading slowness in a traumatic patient with impairment in basic visual processes.

Following a closed-head injury, G.M., a 17-year-old male, showed a reading disturbance in the absence of other cognitive deficits. G.M.'s reading was exceedingly slow, although virtually error free. Analysis of his disorder indicated an inability to read words presented tachistoscopically to the left (spared) visual field. Therefore the reading deficit cannot be interpreted as simply due to the visual field reduction (hemianopic alexia). Reading speed was clearly affected by word length, a finding typical of letter-by-letter reading. Both behavioral and psychophysical testing indicated a selective reduction of visual discrimination and detection (particularly in the range of high spatial frequency information) in portions of the left hemifield which appeared spared upon perimetric examination. Overall, it is suggested that the reading deficit, phenomenologically similar to that of other letter-by-letter readers, can be interpreted as due to a combination of basic visual perturbations: visual field cut with macular splitting and deficit of processing of high spatial frequency information.

Adolescent↗

Neuropsychological deficits associated with a tumour in the posterior corpus callosum: a report of two cases.

This study reports two patients with tumours arising from the splenium of the corpus callosum that caused a memory disturbance consistent with retrosplenial amnesia as well as a variety of cognitive deficits including agraphia, acalculia, constructional apraxia and ideomotor and ideational apraxia involving both hands, but not aphasia. Patients showed disorientation to time and place, impaired recent memory and memorizing capacity; immediate and remote memory were preserved. Despite impaired performance intelligence quotients (IQ), verbal IQ was relatively spared. Patients also showed disconnection symptoms including bilateral crossed visuomotor ataxia and alexia to stimuli presented in the right visual field. In both cases, the tumour of the splenium had provoked surrounding oedema extending to the left parietal and occipital lobes.

Brain Neoplasms↗

Using errorless learning to treat letter-by-letter reading: contrasting word versus letter-based therapy.

Some pure alexic readers have been shown to activate lexical and semantic knowledge under brief presentation conditions. This ability is not seen when letter-by-letter reading accuracy is high or the reading impairment is very severe. It is also unlikely to occur under normal untimed presentation because the pure alexic will make deliberate use of their letter-by-letter strategy. This paper presents data from a moderately severe letter-by-letter reader, FD, who had visual processing problems affecting reading. He also had other mild aphasic characteristics. FD showed implicit reading abilities under brief presentation conditions, being able to make lexical decisions and semantic categorisations well above chance. FD was given two therapy programmes, the first, whole word therapy to exploit this implicit ability and the second to improve letter-by-letter accuracy and speed. FD showed some improvement in reading ability after both therapy programmes, particularly for words of personal interest to him. His letter naming accuracy and reading of visually similar words were the most resistant to change. A striking effect of therapy was the cessation of FD's letter-by-letter reading and the emergence of some of the characteristics of deep dyslexia. Even when therapy concentrated on letter accuracy, FD did not revert back to his original letter-by-letter reading strategy. The results are discussed with reference to the two theories of pure alexia. Some conclusions are drawn about the need for therapists to examine and exploit all residual reading skills when devising therapeutic programmes.

Acoustic Stimulation↗

Cortical sensory loss in a patient with posterior cortical atrophy: a case report.

Patients with posterior cortical atrophy (PCA) who present with initial symptoms of higher visual function deficits eventually develop alexia, aphasia, and components of Balint's syndrome or Gerstmann's syndrome. Recently, pathological findings were reported for these patients that are generally suggestive of Alzheimer's disease even though Creutzfeldt-Jakob disease (CJD) was presumed as an alternative cause of some autopsy-diagnosed PCA cases. Here, we report a case with a four-year progression of cognitive and higher visual function deterioration, and with features not described in previously reported PCA cases (i.e., a distinct sensory complaint and early frontal lobe involvement). To summarize, this case belongs to perceptual-motor syndrome of asymmetric cortical degeneration and the underlying neuropathology is more suggestive of Alzheimer's disease than of Creutzfeldt-Jakob disease.

Atrophy↗

Left hemispatial visual neglect associated with a combined right occipital and splenial lesion: another disconnection syndrome.

Damage to the left occipital lobe and the splenium or forceps major is often associated with pure alexia, thought to be an occipital-temporoparietal disconnection syndrome. A patient with the parallel lesion, a combined right occipital and splenial lesion, showed severe left-sided visual spatial neglect, but no significant neglect in other sensory modalities. This visual neglect might be related to a disconnection between the visual information processed by the left occipital lobe and the right posterior temporal-inferior parietal areas that mediate attention in the left hemispace.

Aged↗

Cognitive and neural mechanisms underlying reading and naming: evidence from letter-by-letter reading and optic aphasia.

We report detailed analysis of language performance in a patient, RMI, a 55-year-old man who presented with a homonymous hemianopsia, optic aphasia, and alexia without agraphia (with letter-by-letter reading) acutely after stroke. MRI showed infarct in the left occipital and medial temporal lobe and hypoperfusion of the entire posterior cerebral artery territory, including the splenium. Extensive language testing revealed severely impaired picture naming and oral reading, with relatively spared tactile naming and recognition of orally spelled words, consistent with impaired access to lexical and semantic representations from vision. In addition, he had a milder deficit in accessing lexical representations for output from all input modalities. RMI's execution of various language tasks provided considerable insight into the mechanisms that underlie oral reading. His performance indicated that both semantic access and orthographic to phonologic conversion mechanisms were partially intact. When information from these two impoverished systems was coupled (the picture of an object presented with its written name), his ability to read/name improved significantly, consistent with the hypothesis that partially accessed semantic information from vision can combine with partially accessed sublexical orthographic to phonologic conversion mechanisms to access phonological representations for output. Furthermore, his written word and picture recognition improved to normal at a time when magnetic resonance perfusion imaging demonstrated reperfusion of the splenium. We interpret these results, as well as results from previous studies in the literature, within a model of the neural regions critical for various cognitive processes underlying reading.

Aphasia↗

Lexical or orthographic agraphia.

A case of agraphia was studied in the framework of the information-processing approach and in relation to comparable studies on alexia. Three dissociations are of interest in this patient's picture: (a) in language production: impairment of writing without impairment of speech; (b) in writing: impairment of spelling without impairment of phoneme-grapheme conversion; (c) in visible language: impairment of writing without equivalent impairment of reading. The implications of these dissociations for any model of linguistic processes are discussed.

Aged↗