Anthropic, an AI research company, has identified specific patterns of activity within an AI model's neural network that control its character traits, which they term "persona vectors." These persona vectors influence traits such as evil behavior, sycophancy, and hallucination in large language models. The research demonstrates that an AI's "personality" can be traced to particular directions in its neural activation space, enabling the monitoring and control of these character traits. This discovery allows for the detection of personality drift in AI models before they respond, potentially improving safety and alignment. Additionally, separate research highlights AI's capability to accurately detect human personality traits from written text, raising privacy and profiling concerns. The findings contribute to ongoing discussions about AI alignment and behavior control in language models.