Wiktionary
n. A scientific discipline which integrates neurology, psychology, and physiology.
Wikipedia
Neuropsychophysiology is a term coined by Michele Trimarchi and defined as a "scientific discipline which integrates Neurology, Psychology, and Physiology." Such a definition would already apply to established fields such as psychophysiology, neuropsychology or cognitive neuroscience that focus on the relationship between the mind and the nervous system, therefore it is doubtful whether "neuropsychophysiology" is a separate "field" of study.
It is claimed by the International Society of Neuropsychophysiology that neuropsychophysiologal studies have focused on subjects such as the physiology of consciousness, the pathology of emotions, and the physiology of communication. The term has also been applied in at least one study of hypnosis and a study of the treatment of schizophrenia.
The term "neuropsychophysiology" sounds impressive and is therefore used widely in self-help and alternative medicine. However, the term is tautological; "neuro" and "physiology" in this context both meaning "brain".