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Angela Bartolo

Publications and source records attributed to Angela Bartolo.

7 recordsLinked to original sources
PubMed2006

Hemispheric specialization in human prefrontal cortex for resolving certain and uncertain inferences.

Uncertainty is a fact of life that must be accommodated in real-world decision making. Although it has been suggested that the right prefrontal cortex (PFC) has a special role to play in decision making under uncertainty, there is very little hard data to support this hypothesis. To better understand the roles of left and right PFCs in reasoning and decision making in situations with complete and incomplete information, we administered simple inference problems to 18 patients with lateralized focal lesions to PFC (9 right hemisphere, 9 left hemisphere) and 22 age- and education-matched normal controls. The stimuli were systematically manipulated for completeness of information regarding the status of the conclusion. Our results demonstrated a 2-way interaction such that patients with left PFC lesions were selectively impaired in trials with complete information, whereas patients with right PFC lesions were selectively impaired in trials with incomplete information. These results provide compelling evidence for hemispheric specialization for reasoning in PFC and suggest that the right PFC has a critical role to play in reasoning about incompletely specified situations. We postulate this role involves the maintenance of ambiguous mental representations that temper premature overinterpretation by the left hemisphere.

Adult↗
PubMed2006

List effect in apraxia assessment.

Imitation tests encompassing intermingled meaningful and meaningless items are normally used to assess ideomotor apraxia, implicitly assuming that they would test the lexical and the non-lexical route, respectively. However, these mixed lists might induce a "list composition" effect similar to that found in word recognition studies where familiar material can be processed via the non-lexical route. This hypothesis was put to test by examining praxis skills of 23 left-hemisphere damaged patients using the same gestures in two formats: pure and mixed lists (i.e., meaningless or meaningful gestures administered separately or intermingled, respectively). Results showed that patients performed better on the imitation task when pure lists were used. Moreover, asymmetries of performance were observed. Patient SL scored better in the imitation of meaningful gestures in the pure list than in the mixed list condition. Patient CA performed poorly in the imitation of meaningless gestures only in the mixed list condition. Dissociations observed in imitation tasks could be biased by the use of mixed lists. Also "pure" lists should be used for the diagnosis of imitation deficits in apraxia.

Adult↗
PubMed2006

Left ipsilesional neglect for visual imagery: a mental image generation impairment?

In this article, we describe a patient, CN, with unilateral left posterior brain damage, who shows a rare occurrence of left ipsilesional neglect limited to mental representations. CN's clinical pattern is consistent with the hypothesis that different mechanisms underlie perceptual and representational neglect. We also discuss an interpretation of representational neglect based on the different involvement of the two hemispheres in visual imagery processes. In particular, left brain lesions do not present the typical strong contralesional bias and may lead to an impairment of mental generation of either side of the image, depending on pre-morbid and methodological factors.

Aged↗
PubMed2006

Humor comprehension and appreciation: an FMRI study.

Humor is a unique ability in human beings. Suls [A two-stage model for the appreciation of jokes and cartoons. In P. E. Goldstein & J. H. McGhee (Eds.), The psychology of humour. Theoretical perspectives and empirical issues. New York: Academic Press, 1972, pp. 81-100] proposed a two-stage model of humor: detection and resolution of incongruity. Incongruity is generated when a prediction is not confirmed in the final part of a story. To comprehend humor, it is necessary to revisit the story, transforming an incongruous situation into a funny, congruous one. Patient and neuroimaging studies carried out until now lead to different outcomes. In particular, patient studies found that right brain-lesion patients have difficulties in humor comprehension, whereas neuroimaging studies suggested a major involvement of the left hemisphere in both humor detection and comprehension. To prevent activation of the left hemisphere due to language processing, we devised a nonverbal task comprising cartoon pairs. Our findings demonstrate activation of both the left and the right hemispheres when comparing funny versus nonfunny cartoons. In particular, we found activation of the right inferior frontal gyrus (BA 47), the left superior temporal gyrus (BA 38), the left middle temporal gyrus (BA 21), and the left cerebellum. These areas were also activated in a nonverbal task exploring attribution of intention [Brunet, E., Sarfati, Y., Hardy-Bayle, M. C., & Decety, J. A PET investigation of the attribution of intentions with a nonverbal task. Neuroimage, 11, 157-166, 2000]. We hypothesize that the resolution of incongruity might occur through a process of intention attribution. We also asked subjects to rate the funniness of each cartoon pair. A parametric analysis showed that the left amygdala was activated in relation to subjective amusement. We hypothesize that the amygdala plays a key role in giving humor an emotional dimension.

Adult↗
PubMed2002

Memory and dating of past events in schizophrenia.

Memory deficits are frequently observed in schizophrenia but their intrinsic characteristics have not been clarified. We studied remote memory in a group of 20 schizophrenics and 20 healthy age and education matched controls using a newly devised public event questionnaire (PEQ) that employs a free recall, progressive cueing and recognition protocol and requires dating of events. Results indicate that patients with chronic schizophrenia perform significantly more poorly on the PEQ than a group of age and education matched controls both in terms of content and dating of events. The number of events recalled does not improve with progressive cuing or recognition. No distinctive pattern was observed in their temporal gradient. There was no significant difference in content scores for pre- and post-onset events in the schizophrenics. These findings indicate that remote memory deficits in chronic schizophrenics arise from deficient encoding rather than from a retrieval deficit secondary to executive dysfunction.

Adult↗