ALFF

2022-05-07: reference:

((Fractional) Amplitude of Low Frequency Fluctuations (f/)ALFF) #

• (Fractional) amplitude of low-frequency fluctuations (fALFF/ALFF) is a metric believed to index spontaneous brain tissue excitability/activity.

• For 5 discrete frequency bands within sets of brain regions implicated in Deja-vu and those comprising the default mode network (DMN). Analyses revealed significantly lower values of fALFF/ALFF for specific frequency bands in the DV relative to the NDV group, particularly within mesiotemporal structures, bilateral putamina, right caudatum, bilateral superior frontal cortices, left lateral parietal cortex, dorsal and ventral medial prefrontal cortex, and the posterior cingulate cortex… We suggest that the erroneous feeling of familiarity arises from a temporary disruption of cortico-subcortical circuitry together with the upregulation of cortical excitability.

• Decreased ALFF is consistent with inhibitory effect on NMDA activity.

• Patients with ADHD had decreased ALFF in the right inferior frontal cortex, left sensorimotor cortex, and bilateral cerebellum and the vermis as well as increased ALFF in the right Anterior Cingulate Cortex, left sensorimotor cortex, and bilateral brainstem.