Posts by Year – 2022

in the field of brain rhythms, one of the rock-solid empirical findings is that frequency increases across development, for alpha and mu rhythms.

in this new 〰️preprint〰️, we also look at waveform shape across development & neurodevelopmental disorders: https://t.co/osCzrClCld pic.twitter.com/J8pfp5h1Dr

you want to extract instantaneous phase of a signal, the textbooks say to narrowband filter before computing the analytic signal. but why?

using a broadband signal, the resulting phase corresponds to the circular mean of the analytic signals of the constituents (here: 🔴=🟢+🔵). pic.twitter.com/uiK1t6q0kN

one reason why I think it's always good to see original spectra before running any kind of fancy analysis: it's quite easy to create oscillations magically out of noise. for instance, in the below demo by grouping trials (which contained only 1/f-activity) by frequency content. pic.twitter.com/50aatLCBz2

IKEA shopping for neuroscientists – lamp ISKÄRNA pic.twitter.com/MG8egSZws6

when recording magnetoencephalography signals, it's of interest where in the brain the activity comes from. in these recordings, participants can move their head with respect to the sensors. this can affect sensor activity recorded for a specific source, adding uncertainty. pic.twitter.com/Lmn88kU6sw

if you combine two rhythms, what determines the resulting modulated signal? one aspect is the difference between the two frequencies, resulting in two spectral peaks left and right from the center frequency. pic.twitter.com/XrXoVb9ZlU

learning how to 3D print! this is a Purkinje neuron from a rat cerebellum. pic.twitter.com/aMVpYov70x

how could one arrive at a traveling wave signal with EEG? take 1 occipital & 1 sensorimotor alpha rhythm. the resulting EEG signal will have varying peak times along the posterior-anterior direction. apparent wave direction will depend on phase shift between rhythms. pic.twitter.com/DTYMBPJI35

there are different models of how the brain responds to rhythmic input, 1) by adjusting an intrinsic oscillator or 2) by a series of evoked responses. adjusting the input rate, the 2 models have different properties, exhibiting a constant or variable phase shift to the input. pic.twitter.com/Elw9qlxmP0

simulated propagating activity waves over a smooth cortical surface vs. over a brain with pronounced gyri and sulci. pic.twitter.com/Z4SJG4HzFh