Final answer:
The statement is true as nuclear episodes in literature are significant scenes marked by their dramatic intensity or psychological importance.
Step-by-step explanation:
The statement in the question, nuclear episodes are particular scenes in the story that are defined by their temporal and spatial boundaries and are notable for their intense dramatic qualities or psychological significance, is generally true. In literary terms, episodes in a narrative, such as in a drama or an epic, are significant sections of the plot that advance the story and develop the characters. These episodes are characterized by their importance in the overarching narrative and how they contain action that is pivotal to the understanding of the story or the development of its characters. For instance, in the case of Orestes as mentioned in the reference material, his episode of madness and subsequent purification is a key plot point that has significant dramatic and psychological implications for the story.