  A new brain model is introduced, based on the Impulse Pattern Formulation
(IPF) already established for modeling and understanding musical instrument and
rhythm perception and production. It assumes the brain works with impulses,
neural bursts, ejected from an arbitrary reference point in the brain, arriving
at other reflecting brain regions, and returning to the reference point delayed
and damped. A plasticity model is suggested to adjust reflection strength in
time. The model is systematically studied with 50 reflection points by varying
the amount of excitatory vs. inhibitory neurons, the presence or absence of
plasticity or external sensory input, and the strength of the input and
plasticity in terms of system adaptation to an input or to the system itself.
The Brain IPF shows adaptation to an external stimulus, which is stronger
without plasticity, showing the active brain not being a simple passive
\emph{tabula rasa}. A relation of 10-20\% of inhibitory vs. excitatory neurons,
as found in the brain, shows a maximum adaptation to an external stimulus
compared to all other relations, pointing to an optimum of this relation
concerning adaptation. When assuming strong brain periodicities only up to
about 100 Hz, the reflection strength of the model is highest for delays of
around 300 ms, corresponding to Event-Related Potential (ERP) timescales of
brain potentials most often found roughly between 100 - 400 ms. The mean
convergence times of the model correspond to short-time memory time scales with
a mean of five seconds for converging IPFs. The Brain IPF is computationally
very cheap, highly flexible, and with musical instruments already found to be
of high predictive precision. Therefore, in future studies, the Brain IPF might
be a model able to understand very large systems composed of an ensemble of
brains as well as cultural artifacts and ecological entities.
