Doctor of Philosophy

dissertationMemory assessment can often alert practitioners and educators to learning problems children may be experiencing. Results of a memory assessment may indicate that a child has a specific memory deficit in verbal memory, visual memory, or both. Deficits in visual or verbal modes of memory could potentially have adverse effects on academic achievement. Past research in the area of memory and academics have shown mixed results, with some studies showing correlations between visual or verbal memory deficits and patterns of academic achievement and other studies showing evidence there is not a predictable pattern. The purpose of the present study was to examine the effects of visual memory deficits upon children's academic achievement in reading, spelling, and arithmetic. Archival data of children's comprehensive neuropsychological evaluations conducted at a private neuropsychology clinic were reviewed and analyzed to determine if children who showed evidence of deficits in visual memory differed significantly on academic achievement measures from a comparison group of children who did not have visual or verbal memory deficits. Overall, the results of this study found that individuals with visual memory deficits showed significantly weaker performance in arithmetic achievement compared to children without memory deficits. Children with visual memory deficits did not differ significantly from children without memory deficits on reading or spelling achievement

On the validity and reliability of the computerized memory interference test for primary Spanish-speaking individuals

In this study, the Computerized Memory Interference Test (CMIT), a derivative of the Picture Memory Interference Test (PMIT) was assessed for reliability, validity and internal consistency with a primary Spanish-speaking sample. Five hypotheses were formulated and tested. For the first hypothesis correlational studies assessing relationships between the CMIT scores and those of the WMS-III, Visual Reproduction subtests were used to establish convergent validity. Hypotheses two and three, produced correlational studies to assess relationships between the CMIT scores and those of the RAVLT and WAIS-III Block Design, Vocabulary and Matrix Resonating subtests. To test the fourth hypothesis, known-group methods were used to assess the reliability of the CMIT. Cronbach\u27s Alpha was used to determine the internal consistency of the CMIT. Results indicated that the CMIT scores and those of the WMS-III, Visual Reproduction subtests correlated at a statistically significant level confirming convergent validity. Results also showed statistically significant correlations between the CMIT scores and the RAVLT subtest scores as well as those of the WAIS-III subtests. Due to these results, discriminant validity was not considered established. However, the CMIT did prove to be sensitive to detecting visual memory deficit, and internal consistency was also established for this population

Episodic and semantic autobiographical memory in temporal lobe epilepsy

Autobiographical memory (AM) is understood as the retrieval of personal experiences that occurred in specific time and space. To date, there is no consensus on the role of medial temporal lobe structures in AM. Therefore, we investigated AM in medial temporal lobe epilepsy (TLE) patients. Twenty TLE patients candidates for surgical treatment, 10 right (RTLE) and 10 left (LTLE), and 20 healthy controls were examined with a version of the Autobiographical Interview adapted to Spanish language. Episodic and semantic AM were analyzed during five life periods through two conditions: recall and specific probe. AM scores were compared with clinical and cognitive data. TLE patients showed lower performance in episodic AM than healthy controls, being significantly worst in RTLE group and after specific probe. In relation to semantic AM, LTLE retrieved higher amount of total semantic details compared to controls during recall, but not after specific probe. No significant differences were found between RTLE and LTLE, but a trend towards poorer performance in RTLE group was found. TLE patients obtained lower scores for adolescence period memories after specific probe. Our findings support the idea that the right hippocampus would play a more important role in episodic retrieval than the left, regardless of a temporal gradient.Fil: Múnera Martínez, Claudia Patricia. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: Lomlomdjian, Ana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: Gori, María Belén. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Terpiluk, Veronica. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Medel, Nancy Ruth. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Solis, Patricia. Universidad Nacional Arturo Jauretche. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Kochen, Sara Silvia. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Universidad Nacional Arturo Jauretche. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos. Provincia de Buenos Aires. Ministerio de Salud. Hospital Alta Complejidad en Red El Cruce Dr. Néstor Carlos Kirchner Samic. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Unidad Ejecutora de Estudios en Neurociencias y Sistemas Complejos; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; Argentin

'Unexpected' spelling difficulty in a ten-year-old child with good reading skills: An intervention case study

We report a single-case intervention study of Alan, a child aged 10;04, who presented with spelling difficulty but good reading skills. Assessment of the potential cognitive functions underlying the spelling difficulty explored phonological abilities, visual memory and letter report. We also assessed print exposure and verbal memory. Results of analysis of spelling performance revealed an effect of word length on accuracy, and spelling errors involving omission, insertion, substitution and transposition of graphemes. Results of the literacy-related assessments indicated that Alan did not have a phonological or visual memory deficit, but he showed impaired performance in the letter-report task when asked to report all the letters in the five-item test array. On the basis of previous research, we hypothesised that Alan’s unexpectedly poor spelling was due to a graphemic buffer deficit. Two different interventions were employed: a lexical-orthographic programme, followed by one aimed at improving sublexical abilities. The results showed a significant increase in spelling accuracy after the lexical-orthographic intervention for the treated word set, and a small improvement for the untrained words that was significant at delayed post-intervention testing. The improvement was shown to persist over time. No improvement in spelling was observed after the sublexical intervention. The study emphasises the importance of a wide assessment in order to investigate cognitive processes underpinning spelling difficulty

Memory In Children With Symptomatic Temporal Lobe Epilepsy.

In children with temporal lobe epilepsy (TLE), memory deficit is not so well understood as it is in adults. The aim of this study was to identify and describe memory deficits in children with symptomatic TLE, and to verify the influence of epilepsy variables on memory. We evaluated 25 children with TLE diagnosed on clinical, EEG and MRI findings. Twenty-five normal children were compared with the patients. All children underwent a neuropsychological assessment to estimate intellectual level, attention, visual perception, handedness, and memory processes (verbal and visual: short-term memory, learning, and delayed recall). The results allowed us to conclude: besides memory deficits, other neuropsychological disturbances may be found in children with TLE such as attention, even in the absence of overall cognitive deficit; the earlier onset of epilepsy, the worse verbal stimuli storage; mesial lesions correlate with impairment in memory storage stage while neocortical temporal lesions correlate with retrieval deficits.72184-

Association between precuneus volume and autobiographical memory impairment in posterior cortical atrophy: Beyond the visual syndrome

Posterior cortical atrophy is a neurodegenerative syndrome characterised by progressive disruption of visual and perceptual processing, associated with atrophy in the parieto-occipital cortex. Current diagnostic criteria describe relative sparing of episodic memory function, but recent findings suggest that anterograde memory is often impaired. Whether these deficits extend to remote memory has not been addressed. A large body of evidence suggests that the recollection of an autobiographical event from the remote past coincides with the successful retrieval of visual images. We hypothesised that the profound visual processing deficits in posterior cortical atrophy would result in impaired autobiographical memory retrieval. Fourteen posterior cortical atrophy patients, eighteen typical Alzheimer's disease patients and twenty-eight healthy controls completed the Autobiographical Interview. Autobiographical memory in posterior cortical atrophy was characterised by a striking loss of internal, episodic detail relative to controls and to same extent as typical Alzheimer's disease patients, in conjunction with an increase in external details tangential to the memory described. The memory narratives of posterior cortical atrophy patients showed a specific reduction in spatiotemporal and perceptual detail. Voxel-based morphometry analysis revealed atrophy of the parieto-occipital cortices in posterior cortical atrophy but relatively spared hippocampi bilaterally, compared with characteristic atrophy of the medial temporal lobes in typical Alzheimer's disease. Analysis of brain regions showing posterior cortical atrophy-specific atrophy revealed a correlation between perceptual details in autobiographical memory and grey matter density in the right precuneus. This study demonstrates remote memory impairment in posterior cortical atrophy despite relatively preserved medial temporal lobe structures. The results demonstrate, for the first time, profound autobiographical memory impairment in PCA and suggest that this is driven by the well-recognised deficits in higher-order visual processing. The findings are discussed in the context of posterior parietal contributions to imagery and memory, and the clinical implications of autobiographical memory impairment for diagnostic and management protocols in posterior cortical atrophy

Characterising subtypes of hippocampal sclerosis and reorganization: correlation with pre and postoperative memory deficit

Neuropathological subtypes of hippocampal sclerosis (HS) in temporal lobe epilepsy (The 2013 International League Against Epilepsy classification) are based on the qualitative assessment of patterns of neuronal loss with NeuN. In practice, some cases appear indeterminate between type 1 (CA1 and CA4 loss) and type 2 HS (CA1 loss) and we predicted that MAP2 would enable a more stringent classification. HS subtypes, as well as the accompanying alteration of axonal networks, regenerative capacity and neurodegeneration have been previously correlated with outcome and memory deficits and may provide prognostic clinical information. We selected 92 cases: 52 type 1 HS, 15 type 2 HS, 18 indeterminate‐HS and 7 no‐HS. Quantitative analysis was carried out on NeuN and MAP2 stained sections and a labeling index (LI) calculated for six hippocampal subfields. We also evaluated hippocampal regenerative activity (MCM2, nestin, olig2, calbindin), degeneration (AT8/phosphorylated tau) and mossy‐fiber pathway re‐organization (ZnT3). Pathology measures were correlated with clinical epilepsy history, memory and naming test scores and postoperative outcomes, at 1 year following surgery. MAP2 LI in indeterminate‐HS was statistically similar to type 2 HS but this clustering was not shown with NeuN. Moderate verbal and visual memory deficits were noted in all HS types, including 54% and 69% of type 2 HS. Memory deficits correlated with several pathology factors including lower NeuN or MAP2 LI in CA4, CA1, dentate gyrus (DG) and subiculum and poor preservation of the mossy fiber pathway. Decline in memory at 1 year associated with AT8 labeling in the subiculum and DG but not HS type. We conclude that MAP2 is a helpful addition in the classification of HS in some cases. Classification of HS subtype, however, did not significantly correlate with outcome or pre‐ or postoperative memory dysfunction, which was associated with multiple pathology factors including hippocampal axonal pathways, regenerative capacity and degenerative changes

Multinodular and vacuolating neuronal tumors in epilepsy: dysplasia or neoplasia?

Multinodular and vacuolating neuronal tumor (MVNT) is a new pattern of neuronal tumour included in the recently revised WHO 2016 classification of tumors of the CNS. There are 15 reports in the literature to date. They are typically associated with late onset epilepsy and a neoplastic vs. malformative biology has been questioned. We present a series of ten cases and compare their pathological and genetic features to better characterized epilepsy-associated malformations including focal cortical dysplasia type II (FCDII) and low-grade epilepsy-associated tumors (LEAT). Clinical and neuroradiology data were reviewed and a broad immunohistochemistry panel was applied to explore neuronal and glial differentiation, interneuronal populations, mTOR pathway activation and neurodegenerative changes. Next generation sequencing was performed for targeted multi-gene analysis to identify mutations common to epilepsy lesions including FCDII and LEAT. All of the surgical cases in this series presented with seizures, and were located in the temporal lobe. There was a lack of any progressive changes on serial pre-operative MRI and a mean age at surgery of 45 years. The vacuolated cells of the lesion expressed mature neuronal markers (neurofilament/SMI32, MAP2, synaptophysin). Prominent labelling of the lesional cells for developmentally regulated proteins (OTX1, TBR1, SOX2, MAP1b, CD34, GFAPδ) and oligodendroglial lineage markers (OLIG2, SMI94) was observed. No mutations were detected in the mTOR pathway genes, BRAF, FGFR1 or MYB. Clinical, pathological and genetic data could indicate that MVNT aligns more with a malformative lesion than a true neoplasm with origin from a progenitor neuro-glial cell type showing aberrant maturation