Biomedical subjects

Fernando Cadaveira

Publications and source records attributed to Fernando Cadaveira.

6 recordsLinked to original sources

PubMed2006

Attentional load affects automatic emotional processing: evidence from event-related potentials.

One open question on the relation between attention and emotion concerns the automatic processing of emotional visual stimuli outside the focus of attention. This study examined to what extent the emotional processing at unattended locations is modulated by the processing load at attended locations. Event-related potentials were measured to task-irrelevant unpleasant and neutral pictures briefly presented at peripheral locations while participants performed a visual central task varying in load (low and high load). Unpleasant pictures elicited larger amplitudes of N1-P2 at parietoccipital and occipital sites than that of neutral pictures. This effect was only significant in the low-load condition. Data suggest that brain responses to affective value of task-irrelevant peripheral pictures are modulated by attentional load at fixation.

Adult↗

PubMed2004

Pre-attentive detection of motion direction changes in normal aging.

Effects of normal aging on pre-attentive detection of changes in motion direction were evaluated. Young, middle-aged, and older subjects performed a visual central task while standard and deviant gratings varying in motion direction were presented outside the focus of attention. A greater negativity in the event-related potentials (ERPs) to deviants was observed in all groups at posterior sites within the N2 latency range. Visual mismatch negativity (vMMN) reached its peak between 145 and 165 ms irrespective of age. However, significant age-related changes observed in vMMN mean amplitude may suggest that the pre-attentive visual detection become less efficient in older subjects. This could lead to age-related deficits in switching attention to potentially salient visual changes.

Adult↗

PubMed2004

Effects of stimulus location on automatic detection of changes in motion direction in the human brain.

We extended the results of a previous report by further exploring the underlying mechanisms of an electrophysiological index of attention-free memory-based detection mechanism to motion-direction changes in the human visual system. By means of presenting bilateral, right- and left-hemifield stimulation in separate conditions, we tried to assess whether the location of the stimuli within the peripheral visual field affected the processing of motion-direction deviations, and to identify brain regions involved in the detection of unattended infrequent changes of motion direction using low-resolution brain electromagnetic tomography (LORETA). Results indicated that the ERP component related to visual change was not affected by stimulus location, and that bilateral temporal and medial regions were activated during this deviance-related response regardless of the hemifield stimulated. The bilateral activation foci observed in this study suggest that brain generators of this deviance-related component could be located at the vicinity of motion processing areas.

Adolescent↗

PubMed2003

Neuropsychological characteristics of young children from high-density alcoholism families: a three-year follow-up.

OBJECTIVE: We performed a follow-up study of a group of young children from high-density alcoholism families (HD children), who were first assessed about 3.5 years ago, with the aim of evaluating verbal span and visuospatial abilities (which differed significantly between HD and control [C] children at the first assessment), as well as other neuropsychological measures. METHOD: In this second assessment, 22 boys and girls were evaluated. They were comparable in family income and parents' level of education. The 12 HD children had an alcoholic father and at least two other alcoholic relatives, whereas the 10 C children had no family history of alcoholism in either the first or second generation. A neuropsychological battery was set up with standardized tasks to measure attention, memory, visuospatial and executive functions. RESULTS: Analysis revealed significant Group x Assessment interactions in the digit span subtest where high-density children increased their performance until it reached that of the control children, and in the Wisconsin Card Sorting Test (WCST) where high-density children did not show the same improvement as the C children with maturation. A main effect was also observed for group factor in perseverative responses of the WCST. CONCLUSIONS: High-density children attain the same level of performance as control children for verbal span, but differences between groups increase over time for executive functioning as measured by the WCST. These results are considered in the context of the developmental delay hypothesis. The small sample size, however, means further studies will be necessary to confirm our findings.

Adolescent↗

PubMed2002

Covert orienting of visuospatial attention in the early stages of aging.

Electrophysiological and behavioral responses were recorded in healthy young (19-23 years) and older (56-66 years) subjects during the execution of a visuospatial attention task. The objective was to test whether covert orienting of visuospatial attention (COVAT) is sensitive to the early stages of aging. All subjects responded faster to targets following valid than invalid cues. The amplitude of the P1 component of visual event-related potentials (ERP) was larger to targets following central valid cues at all SOAs. Subtle age-related changes were observed in P1 amplitude under peripheral cueing. Furthermore, older subjects presented longer reaction times (RTs) and lower P1 amplitudes regardless of the attention condition.

Adult↗

PubMed2002

Consolidation of psychophysiology as a scientific discipline, 1930-1964: a historical note.

The ground covered by psychophysiology throughout the decades prior to its constitution as an independent discipline has not been well documented, despite its historical interest. A bibliometric study of the research published in scientific journals by 66 of the most relevant psychophysiologists from 1930 to 1964, analyzing the contents of the records indexed in the PsycINFO database, gives us an image of the state of the emergent discipline during that period. This study reveals that this was a period of consolidation, marked by the refinement of instruments and procedures, the characterization of measurements, and the establishment of the basic relationships between physiological and psychological variables, the development and validation of basic constructs such as activation, or interest in the study of psychopathology. In these years the foundations of psychophysiology were laid, leading to the formalization of the discipline at the end of the period.

Bibliometrics↗