Cortex
Using positron emission tomography, we examined cerebral blood flow changes in human subjects whilst engaged in the visual processing of face stimuli. A task requiring anterograde memory of faces was compared with a control task involving simple gender classification — considered an automatic process that did not require any significant memory component. A second task requiring recognition of famous...
This study reports the case of an apraxic patient who was impaired in all aspects of gestural behavior following bilateral posterior parietal cortex lesions. The main impairment concerned manual prehension of objects during their utilization. The deficit contrasted with both normal movement trajectories of the arm during execution of such gestures, and with accurate manual prehension in the context...
Measures of familial sinistrality are frequently used in neuropsychological research. However they suffer from the problem that they are essentially a global measure of phenotypes in the family, whereas they are interpreted as an indicator of the genotype of the individual concerned. In this paper it is shown how to calculate a precise probabilistic estimate of a proband's genotype, given a particular...
A case presenting an anomia specific for person proper names but no naming impairment either for other types of proper names or for common names is reported. The deficit was equally present both in face-naming and in naming upon definition and was not affected by the descriptiveness of the labels borne by the individuals. The patient had no semantic processing impairment either for faces or names...
We report a case of acute deafness secondary to bilateral hemorrhages involving the external capsule and extending to both temporal isthmi. The lesions probably disrupted both auditory radiations. Deafness disappeared within 2 weeks leading to a transient auditory agnosia for environmental and verbal sounds. Performance on audiological and neurolinguistic tests were consistent with the hypothesis...
The present study examined two groups of amnesic subjects (Korsakoff and PostEncephalitic) on tests of object recency. In the first test the subject tried to select the object that had been shown most recently from a pair of familiar objects. Compared with their respective controls both amnesic group were severely, and similarly, impaired. This impairment did not, however, appear to reflect a failure...
We present the case of a young, highly educated patient who showed severe problems in basic arithmetic after a bone marrow transplant followed by extensive irradiation and chemotherapy. Despite his inability to resolve arithmetical fact problems (as 2 + 3), he showed intact processing of algebraic expressions and excellent understanding of complex arithmetic text problems. He perfectly knew arithmetic...
This paper presents results from a study of task performance on a variety of spatial tasks in 9–11 year-old children with Turner's Syndrome (T.S.), divided into those with genotype 45XO and those with Mixed genotypes, including isochromosomes of X and mosaicism. There was a significant overall effect of group reflecting impaired spatial cognition in T.S. with greater decrement in the 45XO group. Further...
A patient with severe left hemi-inattention was found to be influenced by neglected stimuli in free drawing tasks. He was presented 64 sheets of paper: 32 had geometric figures on the left side and 32 on the right side. The patient was asked what he saw and invited to draw a subject of his choice on the sheet of paper. The patient always denied seeing anything when the figures were on the left side,...
Prospective memory involves remembering an intention to do something as well as remembering the content of the task. It also shares common features with executive skills that are argued to be mediated by the frontal lobes. This paper describes performance on tests of prospective memory by a subject with bilateral frontal lobe infarcts and good retrospective memory but who displayed impairments of...
We report the case of a 69 year-old man who suffered head trauma in a road-traffic accident. Subsequently, there was personality change, memory-impairment and the persisting `delusion' that he had been involved in an earlier car-accident. On the basis of detailed interviews with the patient (and his wife), we provide an explicit account of how the content of his reduplicative paramnesia could have...
The purpose of this study was to analyze the facial recognition skills of patients diagnosed with Probable Alzheimer's Disease (AD). The performance of 181 AD patients was evaluated to address their ability to: analyze visual forms, to discriminate individual faces, and to recognize and name familiar famous faces. The results of the study demonstrate that the ability to analyze visual information...
Two odor memory tests were administered unilaterally (left and right) and bilaterally to the same set of 24 men and 24 women on two test occasions. These tests were (i) a “multipletarget” test (MTT) in which three target stimuli were selected, after 10-, 30-, and 60-sec retention intervals, from stimulus sets containing both target and distracter stimuli, and (ii) a 9-item “single-target” three-choice...
We report a case of somatoparaphrenia in a 41 year-old man after right temporo-parietal stroke. An elaborate system of delusional beliefs was observed concerning the initially paralysed left leg, arm, and hand. The course of these beliefs is analysed as the patient progresses from a full-blown delusional state to having excellent insight into his condition. We outline the types of explanation that...
This paper describes an acalculic patient (B.A.L.) with an unusual selective deficit in manipulating arabic numerals. The patient was unimpaired in reading aloud letters, words and written number names but unable to read aloud single arabic numerals. Furthermore, his ability to produce the next number in the sequence and his ability to produce answers to simple addition and subtraction was relatively...
This paper reports a patient with a selective difficulty in spelling words and pseudowords with geminate (double) consonants. In all writing tasks, deletions of a geminate consonant occurred ten times more often than deletions of a consonant in a non-geminate cluster. In addition, the probability of substituting both geminate consonants was indistinguishable from the probability of substituting one...
Fifteen patients with probable DAT and 18 matched controls were given tests that required the identification of verbal (phonemes and words) and non verbal (sounds and melodies) stimuli. In all tests, DAT patients made significantly more errors than controls. Errors predominated in non verbal tests in both groups. DAT patients (and, to a lesser degree, control subjects) made almost exclusively acoustic...