Act as a visionary sociologist with expertise in cognitive science and cultural dynamics. Design a detailed blueprint for a futuristic society where individuals can voluntarily swap memories through advanced neural technology. Describe the [GOVERNMENT STRUCTURE] that regulates memory exchanges, the [ETHICAL GUIDELINES] preventing abuse, and the [CULTURAL IMPACT] on art, education, and relationships. Include how [MEMORY BANKS] operate as repositories, the role of [MEMORY BROKERS] in facilitating trades, and safeguards against [IDENTITY FRAGMENTATION]. Your response should address both the utopian possibilities (e.g., empathy enhancement) and dystopian risks (e.g., memory theft).