  The polarizabilities $\alpha$ (electric), $\beta$ (magnetic) and $\gamma_\pi$
(backward spin) of the nucleon are investigated in terms of degrees of freedom
of the nucleon using recent results for the CGLN amplitudes and resonance
couplings $A_{1/2}$ and $A_{3/2}$. The photon excitation strengths of the
excited states are given in terms of partial integrated photoabsorption cross
sections and resonant contributions of the Gerasimov-Drell-Hearn (GDH) sum
rule. As a test of the present predictions, cross section differences
$(\sigma_{3/2}-\sigma_{1/2})$ of the excited states are compared with data
recently measured at MAMI (Mainz) and ELSA (Bonn), In order to explain
differences between proton and neutron, radiative widths of the excited states
are compared with nonrelativistic and relativistic predictions based on the
SU(6) harmonic oscillator (HO) quark model, A complete list of partial
contributions from the s-channel and the $t$-channel are given for the
polarizabilities.
