Final answer:
Semantic and episodic memories are processed and stored in different brain regions, supported by studies showing that damage to specific areas such as the lateral temporal lobe or hippocampus can differentially affect these types of memories.
Step-by-step explanation:
The notion that episodic memories are distinct from semantic memories is evidenced by specific patterns of brain damage affecting memory. Episodic memory refers to the autobiographical events that an individual can recall, such as personal experiences and specific events. It is closely tied with the structures of the medial temporal lobe, particularly the hippocampus. On the other hand, semantic memory involves general knowledge and facts about the world and is typically not tied to personal experience. Damage to different regions affects these types of memories differently. For example, damage to the hippocampus can impair the ability to form new episodic memories, which is known as anterograde amnesia, as seen in the case of patient H.M. In contrast, semantic dementia is characterized by atrophy of the lateral temporal lobes and affects the ability to recall factual information without necessarily affecting the hippocampus or episodic memory systems.
Answer choice (d) states that "persons with semantic dementia show loss of the lateral temporal lobe but not the hippocampal formation," which supports the idea that semantic and episodic memories are processed and stored in different brain regions.