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Functional magnetic resonance imaging (fMRI) uses the blood-oxygenation-level-dependent (BOLD) signal to analyze brain activity in both healthy and diseased populations (Matthews and Jezzard, 2004). fMRI is a noninvasive imaging modality that allows for brain mapping and analysis of changes in brain metabolism (Glover, 2011). Since the 1990s, fMRI has been used to analyze the brain’s response to stimuli, given a specific task protocol, as well as under no stimuli, also known as task-based fMRI and resting-state (RS) fMRI, respectively. Several processes in the brain can result in changes in cerebral hemodynamics and thus a perceivable fMRI signal. Neuronal firing and signaling result in local energy increases and an increase in the cerebral metabolic rate of oxygen. When a subject performs a task or responds to a stimulus, there is a buildup of deoxygenated hemoglobin and a decrease in oxygenated hemoglobin. This then leads to a vasodilatory response causing an increase in blood flow, resulting in an increase in oxygenated hemoglobin. These changes in oxygenated and deoxygenated hemoglobin lead to the generation of the BOLD signal, which can be considered a good proxy of neuronal activation. Since oxygenated hemoglobin is diamagnetic and deoxygenated hemoglobin is paramagnetic, the deoxygenated hemoglobin causes local dephasing in the magnetic field (Zorzi et al., 2021). This causes distortion of the magnetic field leading to an increase in the BOLD signal when deoxyhemoglobin is replaced by oxyhemoglobin. This increased signal is the basis for the BOLD contrast (Matthews and Jezzard, 2004). The magnitude of the fMRI signal is most influenced by venous blood volume in each voxel and indirectly provides information about neuronal firing or the activation of a population of neurons. The BOLD signal has been shown to increase and peak around 3–5 seconds and then fall to baseline (West et al., 2019). This is referred to as the hemodynamic response function (HRF). Most fMRI studies analyze the amplitude of the HRF in response to a stimulus. The width of the HRF additionally provides information on the duration of the response. The latency of the HRF can be measured and represents the delay and timing of brain activation. All of this information can be used to analyze neuronal activity (Lindquist et al., 2009). If multiple stimuli are presented before the end of the previous stimuli, the HRFs overlap, and the final BOLD response is the convolution of all the separate BOLD responses and unmeasured latent neural signal (Yan et al., 2018). The HRF also has a postundershoot period after the peak, which has yet to be fully understood. Current hypotheses are that the undershoot is a continuation of elevated blood volume, continuation of elevated cerebral metabolic rate, or related to ongoing neuronal activity (Bandettini, 2014). Two types of imaging techniques present in current fMRI studies are spiral imaging and echo planar imaging (EPI). EPI is a fast MRI technique that can acquire an entire image in less than a second. Spiral imaging samples the k space, which represents the spatial frequency of an MR image, in a spiral form while EPI samples the k space in a Cartesian manner (Rowe et al., 2009). There are two types of EPI sequences: single shot and multishot EPI (Poustchi-Amin et al., 2001). In single-shot imaging, all the images are obtained in one repetition time, while in multishot EPI, the steps are divided into several TR periods. Both are performed by rapid reversal of the frequency encoding gradient. EPI has many advantages such as decreased imaging time and decreased motion artifacts (Poustchi-Amin et al., 2001).