Nuestros investigadores

Luis Humberto Eudave Ramos

Teoría y Métodos
Facultad de Educación y Psicología. Universidad de Navarra

Publicaciones científicas más recientes (desde 2010)

Autores: Eudave Ramos, Luis Humberto; Martínez Villar, Martín; Luis García, Elkin Oswaldo; et al.
ISSN 1065-9471  Vol. 39  Nº 11  2018  págs. 4196 - 4212
Numerous daily tasks, including car driving, require fine visuospatial tuning. One such visuospatial ability, speed discrimination, declines with aging but its neural underpinnings remain unknown. In this study, we use fMRI to explore the effect of aging during a high speed discrimination task and its neural underpinnings, along with a complete neuropsychological assessment and a simulated driving evaluation in order to examine how they interact with each other through a multivariate regression approach. Beyond confirming that high speed discrimination performance is diminished in the elderly, we found that this deficit might be partly due to a lack of modulation in the activity and connectivity of the default mode network (DMN) in this age group, as well as an over-recruitment of frontoparietal and cerebellar regions, possibly as a compensatory mechanism. In addition, younger adults tended to drive at faster speeds, a behavior that was associated to adequate DMN dynamics and executive functioning, an effect that seems to be lost in the elderly. In summary, these results reveal how age-related declines in fine visuospatial abilities, such as high speed discrimination, were distinctly mediated by DMN functioning, a mechanism also associated to speeding behavior in a driving simulator.
Autores: Eudave Ramos, Luis Humberto; Aznárez Sanado, Maite; Luis García, Elkin Oswaldo; et al.
ISSN 1931-7557  Vol. 11  Nº 4  2017  págs. 986 - 997
Previous research on motor sequence learning (MSL) in the elderly has focused mainly on unilateral tasks, even though bilateral coordination might be impaired in this age group. In this fMRI study, 28 right-handed elderly subjects were recruited. The paradigm consisted of a Novel and a simple Control sequence executed with the right (R), left (L) and both hands (B). Behavioral performance (Accuracy[AC], Inter-tap Interval[ITI]) and associated brain activity were assessed during early learning. Behavioral performance in the Novel task was similar between unilateral conditions whereas in the bimanual condition more errors and slower motor execution were observed. Brain activity increases during learning showed differences between Conditions: R showed increased activity in pre-SMA, basal ganglia and left hippocampus while B showed activity increments mainly in posterior parietal cortex and cerebellum. L did not show any activity modulation during learning. Performance correlates for AC (related to spatial success) and ITI (related to accurate timing) shared a cortico-basal-cerebellar network. However, it was found that the ITI regressor presented additional significant correlations with activity in SMA and basal ganglia in R. The AC regressor showed additional significant correlations with activity in more extended thalamic and cerebellar areas in B. The present findings suggest that, behaviorally, the spatial and temporal components of MSL are impaired in elderly subjects when using both hands. Additionally, differential brain activity patterns were found across hand modalities. The results obtained reveal the existence of a highly specialized network in the dominant hand and identify areas specifically involved in bimanual coordination.
Autores: Luis García, Elkin Oswaldo; Ortiz García, A.; Eudave Ramos, Luis Humberto; et al.
ISSN 1387-2877  Vol. 53  Nº 1  2016  págs. 303 - 313
Background: Frontotemporal lobar degeneration (FTLD) is a progressive dementia characterized by focal atrophy of frontal and/or temporal lobes caused by mutations in the gene coding for sequestosome 1 (SQSTM1), among other genes. Rare SQSTM1 gene mutations have been associated with Paget¿s disease of bone, amyotrophic lateral sclerosis, and, more recently, frontotemporal lobar degeneration (FTLD). Objective: The aim of the study was to determine whether a characteristic pattern of grey and white matter loss is associated with SQSTM1 dysfunction. Methods: We performed a voxel-based morphometry (VBM) study in FTD subjects carrying SQSTM1 pathogenic variants (FTD/SQSTM1 mutation carriers; n¿=¿10), compared with FTD subjects not carrying SQSTM1 mutations (Sporadic FTD; n¿=¿20) and healthy controls with no SQSTM1 mutations (HC/SQSTM1 noncarriers; n¿=¿20). The groups were matched according to current age, disease duration, and gender. Results: After comparing FTD/SQSTM1 carriers with Sporadic FTD, a predominantly right cortical atrophy pattern was localized in the inferior frontal, medial orbitofrontal, precentral gyri, and the anterior insula. White matter atrophy was found in both medial and inferior frontal gyri, pallidum, and putamen. FTD/SQSTM1 carriers compared with HC/SQSTM1 noncarriers showed atrophy at frontal, temporal, and parietal lobes of both hemispheres whereas the MRI pattern found in Sporadic FTD compared with controls was frontal and left temporal lobe atrophy, extending toward parietal and occipital lobes of both hemispheres. Conclusions: These results suggest that fronto-orbito-insular regions including corticospinal projections as described in ALS are probably more susceptible to the damaging effect of SQSTM1 mutations delineatinga specific gene-linked atrophy pattern.



Biología de la Personalidad (MMF). 
Universidad de Navarra - Facultad de Educación y Psicología.

Investigación educativa II (F. Edu y Psic). 
Universidad de Navarra - Facultad de Educación y Psicología.

Prácticum interdisciplinar I (MMF). 
Universidad de Navarra - Facultad de Educación y Psicología.

Psicología de la atención y la percepción (F.Edu y Psic). 
Universidad de Navarra - Facultad de Educación y Psicología.

Trabajo fin de Máster (MPGS). 
Universidad de Navarra - Facultad de Educación y Psicología.