Effect of fMRI acoustic noise on non-auditory working memory task: comparison between continuous and pulsed sound emitting EPI

Abstract

Conventional blood oxygenation level-dependent (BOLD) based functional magnetic resonance imaging (fMRI) is accompanied by substantial acoustic gradient noise. This noise can influence the performance as well as neuronal activations. Conventional fMRI typically has a pulsed noise component, which is a particularly efficient auditory stimulus. We investigated whether the elimination of this pulsed noise component in a recent modification of continuous-sound fMRI modifies neuronal activations in a cognitively demanding non-auditory working memory task. Sixteen normal subjects performed a letter variant n-back task. Brain activity and psychomotor performance was examined during fMRI with continuous-sound fMRI and conventional fMRI. We found greater BOLD responses in bilateral medial frontal gyrus, left middle frontal gyrus, left middle temporal gyrus, left hippocampus, right superior frontal gyrus, right precuneus and right cingulate gyrus with continuous-sound compared to conventional fMRI. Conversely, BOLD responses were greater in bilateral cingulate gyrus, left middle and superior frontal gyrus and right lingual gyrus with conventional compared to continuous-sound fMRI. There were no differences in psychomotor performance between both scanning protocols. Although behavioral performance was not affected, acoustic gradient noise interferes with neuronal activations in non-auditory cognitive tasks and represents a putative systematic confound.

Silent and continuous fMRI scanning differentially modulate activation in an auditory language comprehension task

“…9159], who argued that ''the addition of noise introduced an extra cognitive-perception demand (i.e., signal-to-noise extraction)'', which accounts for insular activation. Furthermore, a recent fMRI study demonstrated insula activity in more distractive conventional fMRI relative to a less disruptive scanning protocol [Haller et al, 2005]. A similar scenario can be found in the context of our study: since enhanced effort was necessary in the noisy scanning environment to retrieve intelligible information from the auditory stimuli, it is plausible that this particular region was significantly more engaged during continuous scanning.…”

“…However, customary functional magnetic resonance imaging (fMRI) is hampered by acoustic noise produced during operation of the MR system, which affects the experimental integrity of auditory fMRI studies [Amaro et al, 2002;Haller et al, 2005;McJury and Shellock, 2000;Moelker and Pattynama, 2003]. In particuConny Schmidt and Tino Zaehle equally contributed to this work.…”

Sex differences in sensory gating of the thalamus during auditory interference of visual attention tasks

“…As an example, for working memory tasks, we and others showed that increases in activation in the PFC and occipital cortices due to higher AN (Haller S et al, 2005;Tomasi D et al, 2005;) differed between men and women (Tomasi D et al, 2005).…”

Acute Aerobic Exercise Increases Cortical Activity during Working Memory: A Functional MRI Study in Female College Students

“…The right middle frontal gyrus, located in the ventral and frontal pole area, is believed to reflect the coordination and shifting of information among multiple cognitive tasks and functions as an important area for executing and regulating working memory [33], [35]. Similarly, the detection of activation in both the lingual and fusiform areas located in the medial occipital cortex distinguished tasks involving different levels of working memory, suggesting that the solving of complex tasks can be attributed to these brain regions [36]. Our finding that acute exercise is associated with these brain regions is consistent not only with our hypothesis but also with recent studies using functional near-infrared spectroscopy (NIRS) [37], [38].…”