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We report the case of a patient who, after sequential bilateral strokes in the occipital regions sparing the primary visual cortex, developed a severe deficit of colour perception. At variance with other reports of acquired achromatopsic patients, she showed a perfectly vivid visual imagery for colours. These findings, together with similar data in domains other than colour processing, challenge the theories which posit that the same cognitive processes are involved in both the perception and the retrieval from memory of a given stimulus.

We describe a patient, RM, who suddenly became amnesic for premorbid autobiographic events in the absence of any known precipitating event. Learning abilities as well as semantic knowledge were normal. Knowledge of famous facts and persons was good, although not perfect. Whether RM suffered from organic or psychogenic isolated retrograde amnesia (IRA) could not be established on the basis of available clinical and neuropsychological elements. Regardless of its aetiology, RM's case respects the boundaries between semantic and episodic memory and so gives further support to the distinction between these two memory systems.

An adolescent boy developed a long-lasting pattern of global aphasia, concomitant to focal (left temporal) EEG abnormalities; this was followed by complete recovery. Laboratory and neuroimaging studies were within normal limits. The possibility of a late-onset Landau Kleffner syndrome is discussed.

Writing and spelling are conceived as concerted actions comprising cognitive planning, motor action and an expressive content. In literate societies the individual use of alphabetic systems is acquired immediately after speech as a "cultural technique". As such these systems demand specific cognitive and motor skills which have been analysed primarily on the basis of neurological and psychiatric syndromes. We distinguish primary developmental disturbances and secondarily acquired disturbances of writing and spelling, categorizing the latter into four essential disturbance areas: linguistic command, motor execution, automatism control and dynamic tonus regulation. The clinical significance of writing and spelling is not confined to its possible disturbances. In pathologically induced restrictions of cognitive functions or of social skills the fact is rather that the written language frequently contributes to the development of individual coping strategies. From the psychodynamic aspect, written communication is characterized principally by its proximity-regulating function.

In this study we investigated the acalculic condition of a patient, C.G., with the classical signs of Gerstmann's Syndrome: finger agnosia; right-left disorientation; a profound agraphia (but with an equally profound alexia) and a remarkably dense acalculia. Using a series of number processing and number knowledge tasks, a selective impairment for numbers was demonstrated. Within the category of numbers C.G. showed a largely preserved ability to deal with numbers below 4, in all tasks and in all modalities, while she was totally unable to deal with numbers above 4. The consistency of responses and the ineffectiveness of cueing indicated that numbers above 4 were lost, rather than hard to access. Further testing showed that this impairment did not result from a more general semantic memory problem, a difficulty in understanding quantities or a deficit in reasoning abilities thought to underlie the concept of numbers. Difficulty with some other ordinal structures was also present, but appeared unrelated to those affecting numbers.

A patient with Korsakoff's syndrome is presented, who showed a selective loss of Autobiographical Memory along with a preserved Semantic Memory. Confabulations were a prominent feature. They only involved Autobiographical Memory and were persistent in time and consistent in content. The implications of these findings for understanding the nature of Autobiographical Memory impairment are discussed.

In a patient with a classical syndrome of pure word deafness following a cerebrovascular accident detailed neuropsychological examination showed an almost absolute inability to name meaningful non verbal sounds, in spite of normal recognition as demonstrated by ability to match the sound with the corresponding natural source. This selective anomia, confined to auditory modality, is discussed in view of the previous researches regarding the general field in naming disturbances, which showed that for the vaste majority of aphasics, anomia was not modality dependent. Besides that the contrasting performance of the patient who showed complete lack of phonemic analysis matched with normal recognition of some acoustic parameters of speech as prosody and stress is discussed.

Phonological processing abilities were studied in a patient who, following focal brain damage, showed selective impairment in non-word reading, writing, and repetition and also a severe short-term memory (STM) deficit specific for auditorily presented verbal material. The patient could execute tasks involving phonemic manipulation and awareness perfectly. Our data, in contrast with earlier observations in a case of developmental phonological dyslexia, show that acquired impairment in non-word reading, writing, repetition, and immediate memory may occur despite good phonological processing abilities. The role of STM in processing meaningless verbal material is discussed.

In a 35-year-old right-handed man who had no personal or family history of left-handedness, left hemiparesis and predominantly motor aphasia suddenly developed following cerebrovascular accident. Clinical and laboratory data, including computerized tomographic scan, showed a clearly defined right hemisphere lesion. On dichotic listening test, a clear-cut right ear extinction was present.

Neuropsychologic and neurolinguistic studies performed on an 11-year-old Landau-Kleffner boy are reported. At age 3 his language began to deteriorate progressively until complete disappearance. At the same time, the patient developed epileptic seizures. When 6 years old, he was taught to match objects to the corresponding written word, and subsequently he was able to learn reading and writing to such extent that he could attend primary school. BAER and primary cortical auditory responses were normal, whereas late cortical components were grossly retarded and distorted. Phonemic discrimination, identification, and production were absent, and in contrast, lexical-semantic abilities tested through reading and writing were normal. In visual STM tasks, phonologic mediation was absent. The role of phonologic mediation in language acquisition is then hypothesized.

A 19-year-old woman is described who, following an acute episode of eclampsia during pregnancy, displayed a complex neuropsychological syndrome. Along with a mild pattern of conduction aphasia, she showed a severe apraxia, total agraphia, marked constructional disturbances and was unable to reach targets outside and on her body and to perform accurate motor tasks under visual, tactile and proprioceptive control. These symptoms are discussed as the results of a disconnexion syndrome and related to the C.T. scan findings.

Discrimination and identification of emotions in human voice was studied in normal controls and in 4 groups of brain-damaged subjects, subdivided along the right/left and anterior/posterior dimensions. Results showed a failure of right-brain-damaged patients, the right posterior group being significantly worse than all the other groups. Qualitative differences emerged as well: both a conceptual and an acoustic deficit seem to contribute to right posterior patient performance.

A tactile version of the Vanderplas and Garvin random shapes was given to 80 right-handed subjects, ranging in age from 6 to 13 years. Complexity was constant across the patterns: half of them were chosen from the High Association Group while the remaining patterns were selected from the Low-Association Group. Stimuli were dichhaptically presented, each pair being composed of a High Association and Low Association stimulus. The subject's response was given on each trial by pointing to the corresponding shapes froma visual display presented following the removal of the test stimuli. Analysis of the data showed that age of subjects, hemisphere (R.H. better than L.H.) and Association Value (High Association better than Low Association) were significant factors in recognition. Sex was not significant as well as none of the the interactions. Results were discussed in terms of hemispheric specialisation.

A sentence-reading test was devised in order to assess the aphasic's ability to detect errors in written discourse. One hundred pairs of sentences, each containing one correct and one erroneous sentence, were presented to the patients, who were required to locate the error in one of the two sentences. So that comprehension in the auditory and visual modalities might be compared, the identical test was administered orally to a subset of the aphasic population. Contrary to expectations, there was no difference in overall scores between patients with anterior and posterior pathology. Anterior patients performed somewhat better on the oral version, posterior patients on the written version of the test. Finally, an examination of errors revealed a regular order of difficulty in sentences which featured contradictions to "real-world" knowlege, irrespective of the locus of brain damage, while the order of difficulty of sentences featuring syntactic deviations differed appreciably, depending on the locus of lesion. An attempt is made to relate these findings to current experimental and clinical knowledge.

A dissociation between spared spontaneous and impaired writing on copy is described in a patient with severe limb and constructional apraxia. Visual-perceptual abilities were normal as well as oral language and reading. The findings are discussed in the light of an information processing model of writing.

Sensitivity and criterion were studied on an attention task requiring detection of new stimuli for a group of 20 patients with unilateral hemispheric damage restricted to the anterior or posterior areas. Patients performed a simple attention task, in which the presence of a novel stimulus had to be detected against the repetition of the same stimulus repeated. Only the site of the lesion (anterior vs posterior damage) influenced the performance of the task. In fact, frontal patients had both lower capacity to discriminate between signals and nonsignals and lower confidence in their responses.

A multiple choice test was devised in order to assess some aspects of the aphasic's semantic field; patient's task was to match a given picture with one out of three alternatives: one of them was linked by a class relationship, one was linked by a property relationship and the last was an unrelated item. Results clearly show that Broca's aphasics make their choice according to class criteria whereas Wernicke's and controls make their choice according to property criteria. Results are discussed in the light of Jakobson linguistic hypothesis which postulates that Broca's and Wernicke's aphasia are subdued by a contiguity and similarity disorder.

A follow-up study was undertaken in order to investigate the outcome of recovery from right and left hemiplegia on simple motor function and activities of daily living. The role of concomitant neurophysiological deficits was also investigated. The main results indicate that after six months from onset, left hemiplegics show a lesser degree of improvement in independence and social adjustment coupled with a tendency to a poorer recovery of motor function than the corresponding group of right hemiplegics. Unilateral spatial neglect, which is more frequent and severe in the group of left hemiplegics, seems to be crucial in hampering their performance.

Musical segments convey at least two kinds of meaning: The "real-world" events referred to by lyrics and by occasions of performance constitute musical denotation: the formal expressive patterns suggested by such constituents as pitch, timbre, and intensity constitute musical connotation. To ascertain sensitivity to these musical facets among brain-injured patients, tests assessing appreciation of musical denotation and connotation were administered to unilaterally brain-injured subjects in the United States and Italy. On the musical denotation test, right hemisphere patients excelled on items where knowledge of lyrics was required; in contrast, anterior aphasics surpassed both posterior aphasics and right hemisphere patients on items where acquaintance with lyrics was unnecessary. On the musical connotation test, right hemisphere patients performed relatively better in matching sound patterns to temporally-sequenced designs than to gestalten; these patients also performed better than left hemisphere patients on a number of other dimensions. The relatively high performance of posterior aphasics on the connotation test, along with the lack of correlation between connotative and denotative scores received by aphasic patients, suggest a behavioral and neurological dissociation between the two forms of musical sensitivity.

Given a pattern consisting of x1, x2,..., xn similar elements and y1, which is perceived as different from the former, it is more plausible to assert that y is not x rather than to assert that x is not y (Wason, J. verb. Learn verb. Behav. 4, 7-11, 1965). In order to appreciate such a difference, the entire set has to be considered. Right-hemisphere brain-damaged patients were submitted to a series of visually presented patterns, each pattern consisting of seven similar items and one dissimilar item. Their task was to complete a statement referring to a single element of each pattern. Statements were either simple affirmative or negative sentences. Errors and reaction times were recorded. Patients with a right-hemisphere injury were found to be insensitive to the plausible-implausible dimension in completing negative sentences. It is hypothesized that right-hemisphere brain-damaged patients are less adequate in this task because they are less capable in putting each element into the visual context.

We report on a patient diagnosed as having ganglioneuroblastoma, an uncommon disease entity. The results of clinical examination and complementary tests, including a descending urogram and ultrasound evaluation are presented. The surgical procedure employed is described and the result of pathological analysis of the surgical specimen is presented. The literature is reviewed highlighting the most important criteria.

Different strategies in copying designs were investigated in unilaterally brain-damaged patients. Site of lesions (right or left) and presence or absence of aphasia, seen as a planning disorder, were taken in consideration. Aphasic patients proved to be more inclined to use an analytic strategy rather than a global one, differing from both other brain-damaged patients and normals. A comparison between patients with right and left brain lesion failed to yield a significant difference.

Acquired stuttering (AS) can follow unilateral right, left or bilateral hemispheric lesion, and can, but not necessarily, coexist with aphasia. In this paper we experimentally tested motor programming skills in a patient with AS of vascular origin. Motor programming consists in the structuration of the whole sequence of response prior to the onset of the first response element of a sequence of responses. Chronometric studies have shown that the time to initiate a sequence of manual responses is a function of the characteristics of the forthcoming sequence of responses. In our patient, reaction times involving single motor responses performed by right hand were within normal limit. On the contrary, when the task required a sequence of motor responses, there was a consistent difficulty in following the sequence: moreover, in the few correct sequences, reaction time analysis showed a lack of motor programming. It is suggested that AS could be the speech epiphenomenon of a more generalized disturbance of motor programming.

We investigated the effect of unilateral brain lesions on visual discrimination of low-, middle- and high-frequency gratings. The performance of patients with right hemisphere lesions was significantly impaired compared with that of both controls and patients with left hemisphere lesions. This impairment was largely limited to patients with right posterior hemispheric lesions and was present with all spatial frequencies. These findings run counter to the hypothesis that high and low spatial frequencies are preferentially processed by different hemispheres.