The Relationship Between Dopamine Neurotransmitter Dynamics and the Blood-Oxygen-Level-Dependent (BOLD) Signal: A Review of Pharmacological Functional Magnetic Resonance Imaging

Abstract

Functional magnetic resonance imaging (fMRI) is widely used in investigations of normal cognition and brain disease and in various clinical applications. Pharmacological fMRI (pharma-fMRI) is a relatively new application, which is being used to elucidate the effects and mechanisms of pharmacological modulation of brain activity. Characterizing the effects of neuropharmacological agents on regional brain activity using fMRI is challenging because drugs modulate neuronal function in a wide variety of ways, including through receptor agonist, antagonist, and neurotransmitter reuptake blocker events. Here we review current knowledge on neurotransmitter-mediated blood-oxygen-level dependent (BOLD) fMRI mechanisms as well as recently updated methodologies aimed at more fully describing the effects of neuropharmacologic agents on the BOLD signal. We limit our discussion to dopaminergic signaling as a useful lens through which to analyze and interpret neurochemical-mediated changes in the hemodynamic BOLD response. We also discuss the need for future studies that use multi-modal approaches to expand the understanding and application of pharma-fMRI.

Dopamine is a double-edged sword: dopaminergic modulation enhances memory retrieval performance but impairs metacognition

“…Also, the observed memory effects might stem from interactions with other neurotransmitter systems (especially noradrenaline [23]) and be tightly linked to specific doses determining the amount of presynaptic vs. postsynaptic blockade [70]. Eventually, additional studies using multi-modal methodological approaches [71] will be necessary to resolve these contradictory drug findings as well to examine the specificity of dopaminergic effects on memory retrieval in more detail.…”

Prokinetic meranzin hydrate from Chaihu-Shugan-San improves depression-like behaviors and hypomotility in rats via ghrelin and neurocircuitry

“…The inside/outside counterparts indicate causalities. Here, each HTB circuit comprising comorbid-like pro les is different from the 19 other circuits identi ed from BOLD activated areas related to pathogenesis, therapy, and pharmacology for single diseases [17][18][19][20][21][22][23][24][25][26][27][28][29]. FS is widely used as a behavioral paradigm to assess depressive behaviors [52], but hypomotility has been overlooked.…”

Hemodynamic responses are abnormal in isolated cervical dystonia

“…A number of recent fMRI studies have highlighted that changes in dopamine signaling can modulate the hemodynamic response in healthy individuals (Alavash et al, 2018;Bruinsma et al, 2018;Guitart-Masip et al, 2016). A number of recent fMRI studies have highlighted that changes in dopamine signaling can modulate the hemodynamic response in healthy individuals (Alavash et al, 2018;Bruinsma et al, 2018;Guitart-Masip et al, 2016).…”

“…Furthermore, gamma-aminobutyric acid (GABA) released from interneurons may also act directly on astrocytes or blood vessels and cause vasodilation through GABA-A receptor-mediated effects (Kocharyan, Fernandes, Tong, Vaucher, & Hamel, 2008). We recently reported that CD is associated with an increased availability of GABA-A receptors in the primary motor cortex (Berman et al, 2018) (Alavash et al, 2018;Bruinsma et al, 2018;Guitart-Masip et al, 2016). In individuals with focal hand and laryngeal dystonia, performance of motor tasks involving muscles both affected and unaffected by dystonia was found to be associated with abnormal striatal dopaminergic neurotransmission .…”