Complex sentence: However, Morel employed the phrase in a purely descriptive sense and he did not intend to delineate a new diagnostic category and his traditional conception of dementia differed significantly from that employed in the latter half of the nineteenth-century.
Split into simpler sentences: However, Morel employed the phrase in a purely descriptive sense and he did not intend to delineate a new diagnostic category. Moreover, his traditional conception of dementia differed significantly from that employed in the latter half of the nineteenth-century.