Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dynamic and integrated mechanical movements of a rat brain associated
  with evoked potentials   By using a piezoelectric sensor, it was demonstrated that the visual evoked
potential of a rat brain was accompanied by mechanical movements of the brain
when it was excited. A phase of upward movement was found to be followed by a
phase of downward movement. The largest upward movement was a rise in swelling
pressure on the order of 100 micro gram, which was about 40 times larger than
that of the bullfrog sympathetic ganglion. The waves of mechanical movements
were more complicated than those of the evoked potentials. These findings are
thought to be due to the fact that the evoked potentials are propagated from
the immediate surroundings of the sensor, while the mechanical signals are
produced from anywhere beneath the piezo sensor. The mechanisms of mechanical
movements propagated in the brain by electrical stimulation are discussed.

32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex