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Giovanni Augusto Carlesimo

Publications and source records attributed to Giovanni Augusto Carlesimo.

8 recordsLinked to original sources
PubMed2006

Acquired amnesia in childhood: a single case study.

We report the case of C.L., an 8-year-old child who, following the surgical removal of an ependymoma from the left cerebral ventricle at the age of 4 years, developed significant difficulties in retaining day-to-day events and information. A thorough neuropsychological analysis documented in C.L. a severe anterograde amnesic syndrome, characterised by normal short-term memory, but poor performance on episodic long-term memory tests. In particular, C.L. demonstrated virtually no ability to recollect new verbal information several minutes after the presentation. As for semantic memory, C.L. demonstrated general semantic competencies, which, depending on the test, ranged from the level of a 6-year-old girl to a level corresponding to her actual chronological age. Finding a patient who, despite being severely impaired in the ability to recollect new episodic memories, still demonstrates at least partially preserved abilities to acquire new semantic knowledge suggests that neural circuits implicated in the memorisation of autobiographical events and factual information do not overlap completely. This case is examined in the light of growing literature concerned with the dissociation between episodic and semantic memory in childhood amnesia.

Amnesia, Anterograde↗
PubMed2006

Short-term memory deficits are not uniform in Down and Williams syndromes.

Neuropsychological investigation of the development of the mnesic function in mental retardation has primarily focused on evaluating short-term memory (STM). Studies have often documented a reduced verbal short-term memory span in individuals with mental retardation and with Down syndrome in particular, compared to groups of mental age-matched controls. However, recent evidence suggests that verbal short-term memory is not equally impaired in all individuals with mental retardation. Findings in children with Williams syndrome are particularly relevant in this regard. Also, data concerning STM for visual information suggest that visual-object and visual-spatial working memory may be differently compromised in people with mental retardation. In particular, individuals with Williams syndrome exhibit specific difficulties in visual-spatial but not in visual-object working memory tasks compared to typically-developing children matched for mental age. Instead, people with Down syndrome show reduced performance in both visual-spatial and visual-object tests. Taken together, these results reinforce the view that intellectual disability is not a unitary condition characterized by homogeneous slowness of cognitive development but a variety of conditions in which some cognitive functions may be more disrupted than others. The finding that the working memory deficit in individuals with Williams and Down syndrome may be qualitatively differentiated also supports the hypothesis that it is not simply a manifestation of general cognitive impairment but, rather, the expression of a specific deficit of a discrete cognitive ability.

Amnesia↗
PubMed2006

Evidence from two genetic syndromes for the independence of spatial and visual working memory.

This study aimed at investigating the possible dissociation between visual-object and visual-spatial working memory (WM) in individuals with Williams syndrome (WS) and Down syndrome (DS). Four study groups were included: WS group (10 males, 5 females) with a mean chronological age (CA) of 19 years 8 months (SD 6y 1mo) and a mean mental age (MA)of 6 years 11 months (SD 1y 5mo); WS comparison group (7 males, 8 females) comprised of typically developing children with a mean CA of 6 years 10 months (SD 10mo) and a mean MA of 6 years 11 months (SD 8mo)matched as a group with the participants with WS on the basis of mental age; DS group (11 males, 7 females) with a mean CA of 15 years 10 months (SD 5y 8mo) and a mean MA of 5 years 2 months (SD 8mo); and DS comparison group (10 males, 8 females) with a mean CA of 5 years and 1 month (SD 7mo)and a mean MA of 5 years 2 months (SD 8mo) selected to match the DS group on the basis of mental age. They were all administered tests that explored visual perception (Visual Perception Test - Subtest 4 and Line Orientation tests), visual imagery (imaging the colour of objects and the tail length of well-known animals), spatial imagery (mental rotation of visually presented or verbally evoked objects), and WM for visual-object and visual-spatial information. Individuals with WS exhibited specific difficulties in the visual-spatial, but not the visual-object, WM task. Instead, people with DS showed reduced performance in both tests. However, whereas the observed deficit in individuals with DS persisted when perceptual abilities were taken into account, the deficit in individuals with DS was compensated when their scores were adjusted for performance on perceptual tasks. These results support the hypothesis of a dissociation within the sketch-pad slave system in the WM model and reinforce the view of intellectual disability as a non-unitary condition.

Adolescent↗
PubMed2005

Visual and spatial long-term memory: differential pattern of impairments in Williams and Down syndromes.

This purpose of this study was to investigate visual-object and visual-spatial long-term memory (LTM) abilities in individuals with Williams syndrome (WS) and Down syndrome (DS). Four groups comprised of 15 participants were included: WS group (10 males) with a mean chronological age (CA) of 18 years 5 months, SD 6 years 4 months, and mean mental age (MA) of 6 years 8 months, SD 1 year 5 months; WS control group (eight males) comprised of typically developing children (CA mean 6y 7mo, SD 8mo); DS group, (10 males, CA mean 16y 5mo, SD 5y 10mo; MA mean 5y 4mo, SD 8mo); and DS control group (seven males) formed by typically developing children (CA mean 5y 6mo, SD 7mo). In the WS and DS groups mental age and IQ were evaluated with the Form L-M of the Stanford-Binet Intelligence Scale. Results showed that individuals with WS showed decreased learning of visual-spatial material but substantially typical learning of visual-object patterns as compared to a group of mental-age-matched typically developing children. Individuals with DS showed the opposite profile, i.e. typical learning of visual-spatial sequences but impaired learning of visual-object patterns. These results, showing an interesting double dissociation between these two genetic syndromes in the learning of visual-object patterns as opposed to visual-spatial data, support the interpretation of learning disability* as a heterogeneous condition, characterized by potentially very different qualitative profiles of cognitive impairment.

Adolescent↗
PubMed2004

Spatial working memory deficits in children at ages 3-4 who were low birth weight, preterm infants.

The aim of this study was to investigate attention and perceptual and spatial working memory abilities in preterm, low birth weight preschool children without evident brain disorders as determined by normal cerebral ultrasound findings and normal motor development. The authors evaluated 19 preterm and 19 typically developing children who were matched for IQ and chronological age. Results indicated that children born prematurely without major neurological deficits and with a normal cognitive level may have specific difficulty in sustained attention, visuospatial processing, and spatial working memory when evaluated at ages 3-4. This finding is relevant for understanding the qualitative aspects of cognitive development in preterm children and the neurobiological substrate underlying this development.

Attention↗
PubMed2003

Visual and spatial working memory dissociation: evidence from Williams syndrome.

This study aimed at investigating the possible dissociation between visual and spatial working memory (WM) by means of two different experiments. In the first experiment, a WM test for visual material and for spatial information was given to a group of 202 normally developing children (chronological age 7 years 5 months, SD 1.6 years; 109 males, 93 females). Results document a different developmental trend in the two span tests. In the second experiment, we presented the same visual and spatial WM tests to a group of 13 individuals with Williams syndrome (WS), seven males and six females (chronological age mean 18 years 3 months, SD 5.1; mental age mean 7 years 2 months, SD 1.5 years), and to a control group of 26 typically developing children 14 males and 12 females matched for mental age (mean 7 years 2 months, SD 1.4). The results of this second experiment show that, on average, the spatial span obtained by individuals with WS was significantly lower than control participants, but visual span was comparable in the two groups. Our data support the hypothesis of a dissociation within the visuo-spatial sketch pad slave system in the WM model.

Amnesia↗
PubMed2003

Dopaminergic modulation of visual-spatial working memory in Parkinson's disease.

Visual-spatial working memory (WM) impairment is frequently associated with the early stage of Parkinson's disease (PD). The aim of this study was to evaluate the performance of a group of PD patients in visual-spatial and visual-object WM tasks and to investigate the effect of administering the dopaminergic agonist apomorphine (experiment 1) or the dopamine precursor L-dopa (experiment 2) on the performance of tests assessing these functions. To study WM processes, the PD patients and age-matched normal controls were given an n-back task paradigm. In both experiments, the PD patients were submitted to two evaluations: one after a 12-hour therapy washout and the other 15 min after a subcutaneous infusion of apomorphine (average 0.04 mg/kg) or 20/30 min after L-dopa intake (200 mg p.o.). The apomorphine infusion had a worsening effect on reaction times in both visual-spatial and visual-object WM tasks, but it did not influence performance accuracy. Instead, L-dopa administration had a ameliorative effect on accuracy and reaction times in both visual-spatial and visual-object tasks. These results highlight the role of dopamine in the modulation of the WM function in PD patients.

Apomorphine↗