Frontal brain activation during a Working Memory task: a time-domain fNIRS study

Molteni E., Baselli G., Bianchi A. M., Caffini M., Contini D., Spinelli L., ...More

Conference on Photonic Therapeutics and Diagnostics V, San-Jose, Costa Rica, 24 - 26 January 2009, vol.7161 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 7161
  • Doi Number: 10.1117/12.808972
  • City: San-Jose
  • Country: Costa Rica
  • Keywords: near infrared spectroscopy, optical imaging, time-resolved imaging, working memory, sustained attention, NEAR-INFRARED SPECTROSCOPY, PREFRONTAL CORTEX, ATTENTION, SYSTEM, BOLD, FMRI
  • Istanbul University Affiliated: No

Abstract

We evaluated frontal brain activation during a working memory task with graded levels of difficulty in a group of 19 healthy subjects, by means of time-resolved fNIRS technique. Brain activation was computed, and was then separated into a "block-related" and a "tonic" components. Load-related increases of blood oxygenation were studied for the four different levels of task difficulty. Generalized Linear Models were applied to the data in order to explore the metabolic processes occurring during the mental effort and, possibly, their involvement in short term memorization. Results attest the presence of a persistent attentional-related metabolic activity, superimposed to a task-related mnemonic contribution. Moreover, a systemic component probably deriving from the extra-cerebral capillary bed was detected.