Download Os textos são da exclusiva responsabilidade dos autores

Os textos são da exclusiva responsabilidade dos autores
All texts are of the exclusive responsibility of the authors
POSTERIOR PARIETAL CORTEX INVOLVEMENT IN SKILL LEARNING
Sara Cavaco1,2, Steven W. Anderson2
1 - Laboratory of Neurobiology of Human Behavior, Centro Hospitalar do Porto;
2- Division of Behavioral Neurology and Cognitive Neuroscience, University of Iowa Carver
College of Medicine
Grant nº 201/08
Background: Acquisition of novel perceptual or perceptual-motor skills appears to depend on
multiple brain areas, including the posterior parietal cortex (PPC). Functional neuroimaging studies
have found that the initial, more attentionally demanding stage of skill learning is associated with
greater activity on the PPC. This activation tends to decrease with extensive practice. To date, no
human lesion study has systematically analyzed the putative involvement of this cortical area in
skill learning.
Objectives: To explore: 1) the association between lesion on the PPC and behavioral performance
in a series of perceptual (i.e., mirror reading) and perceptual-motor (i.e., mirror tracing and rotary
pursuit) tasks; and 2) the contribution of attention and explicit knowledge to the acquisition of new
perceptual and perceptual-motor skills.
Methods: 10 subjects with “acute” PPC damage (PPC-A group) and 10 subjects with “acute”
damage in other cortical areas (OCA-A group) will be selected from Centro Hospitalar do Porto’s
neurology clinic. 20 subjects with “chronic” to the PPC damage (PPC-C group) and 20 subjects
with “chronic” damage in other cortical areas (OCA group) will be drawn from the Patient Registry
of the Division of Behavioral Neurology and Cognitive Neuroscience at the University of Iowa
Carver College of Medicine. It will be considered “acute” or “chronic” damage if time since onset
of the neurological event is respectively <3 months or >12 months. All patient subjects will undergo
thorough neurological, neuroimaging, and behavioral examinations. Behavioral data will be
collected from 70 demographically matched healthy subjects recruited in the community (i.e., 30
from Porto and 40 from Iowa City).
The behavioral examination will include 3 skill learning paradigms (i.e., Mirror Reading, Mirror
Tracing, and Rotary Pursuit), as well as measures of attention, declarative memory, visuospatial
perception, executive functions, and manual dexterity. Performance time and number of errors will
be used as dependent measures. For each skill learning paradigm, baseline performance and
learning rate will be analyzed.
Preliminary results: The study is currently recruiting participants both in Portugal and in USA.