[Abstract Title]. - Society for Neuroscience

Executive function impairment is a common feature in patient populations with frontal lobe
pathologic abnormalities, such as schizophrenic, depressed and frontal lobe lesion patients. The
Tower of London test (TOL) is a well-known neuropsychological tool to evaluate executive
function, as it is sensitive in revealing deficits in patient planning performance compared to
healthy controls. Neuroimaging studies have shown that brain activation during TOL
performance involves a distributed network that relies markedly on the integrity of the
dorsolateral prefrontal cortex.
This study was designed to examine the neuronal bases of planning performance and associative
learning in the TOL test and to assess the functional changes associated with the effects of tDCS
administration over the left dorsolateral prefrontal cortex on BOLD signal. Over three sessions
we studied the TOL performance of 17 healthy participants (7 men and 10 women) during 15
min. of active anodal, cathodal and sham tDCS. A post-tDCS block of the TOL test was
administered for each session, however measurement in the magnetic resonance scanner
occurred during sessions one and three only.
As reported by Dockery et al. (2008 submitted), it was proposed that performance gains would
result from phase-specific tDCS application with cathodal preceding anodal tDCS, while sham
tDCS would result in no change. No influence on performance accuracy was predicted; however
significant improvement in planning would be indexed by reaction time. An accelerated learning
effect across sessions was also predicted. tDCS may provide a tool to improve the cognitive
function of patients with frontal lobe pathologies or learning disabilities by strengthening the
connections in pathways associated with the damaged hemisphere.
References
Baudewig, J., Nitsche., M.A., Paulus, W. & Frahm, J. (2001). Regional modulation of BOLD
MRI responses to human sensorimotor activation by transcranial direct current stimulation.
Magn Reson Med. 45, 196-201.
Disclosures: C. Dockery , None; T. Gaber, None; B. Varkuti, None; R. Hückel-Weng,
None; N. Birbaumer, None.
Poster
288. Working Memory: Disorders, Genes and Connectivity
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 288.11/RR18
Topic: F.01.f. Working memory
Support: NARSAD
MSFHR Research Scholar Award