RT Journal Article
SR Electronic
T1 Progressive changes in a recognition memory network in Parkinson's disease
JF Journal of Neurology, Neurosurgery & Psychiatry
JO J Neurol Neurosurg Psychiatry
FD BMJ Publishing Group Ltd
SP 370
OP 378
DO 10.1136/jnnp-2012-302822
VO 84
IS 4
A1 Segura, Bàrbara
A1 Ibarretxe-Bilbao, Naroa
A1 Sala-Llonch, Roser
A1 Baggio, Hugo Cesar
A1 Martí, María Jose
A1 Valldeoriola, Francesc
A1 Vendrell, Pere
A1 Bargalló, Nuria
A1 Tolosa, Eduard
A1 Junqué, Carme
YR 2013
UL http://jnnp.bmj.com/content/84/4/370.abstract
AB Background In a previous functional MRI (fMRI) study, we found that patients with Parkinson's disease (PD) presented with dysfunctions in the recruitment of recognition memory networks. We aimed to investigate the changes in these networks over time. Methods We studied 17 PD patients and 13 age and sex matched healthy subjects. In both groups fMRI (recognition memory paradigm) and neuropsychological assessments were obtained at baseline and at follow-up. To analyse changes over time in functional networks, model free (independent component analysis) analyses of the fMRI data were carried out. Then, a cross correlation approach was used to assess the changes in the strength of functional connectivity. Results At follow-up, patients showed reduced recruitment of one network, including decreased activation in the orbitofrontal cortices, middle frontal gyri, frontal poles, anterior paracingulate cortex, superior parietal lobes and left middle temporal gyrus, as well as decreased deactivation in the anterior paracingulate gyrus and precuneus. Cross correlation analyses over time showed a decrease in the strength of functional connectivity between the middle frontal gyrus and the superior parietal lobe in PD patients. Conclusions Model free fMRI and cross correlation connectivity analyses were able to detect progressive changes in functional networks involved in recognition memory in PD patients at early disease stages and without overt clinical deterioration. Functional connectivity analyses could be useful to monitor changes in brain networks underlying neuropsychological deficits in PD.