Amedeo Modigliani's nude art is usually presented as an integral part of his painted work, but in this author's opinion Modigliani's nude art should be seen as separate from his (non-nude) portraits. In part this is a matter of methodology: While his non-nudes contain many abstract artefacts, such as elongations and other deformations of faces, his nude art is closer to reality. One might say the the people portrayed in Modigliani's non-nudes are subject to his abstract whims, while the models of his nude art dictate the way he pictures them by their natural form.
Another conspicuous difference is a matter of intensity and atmosphere. As a person, Modigliani was profoundly burdened by the monotony of daily life, leading to his alcoholism and drug use, and in his art to the boredom and sadness that his non-nude paintings reflect. Very different, in that sense, is his nude art. All his nude art paintings show an intensity and intimacy that cannot be found in any of his non-nudes, not even his portraits of Jeanne Hébuterne. Some of his paintings show symbols, but the style of his non-nudes can never be called symbolism, too sobering daily life was to him. When Modigliani's style would be able to escape from daily reality and be regarded as symbolism, it's in his nude art painting "Large nude" from 1917.
Large nude, 1917
As Beatrice Hasting once remarked, "Modigliani could never paint when he had used hashish". Apparently, while at work, only through his nude art Modigliani would be able to lift his spirit above daily reality.