Identifying Behavioral Bias in Investment Preference

James is a financial advisor helping a high-net-worth client to construct a personalized investment portfolio. The client is relatively risk-averse but has expressed a strong preference for investing in technology stocks due to their recent high performance. James recalls a concept from behavioral finance that pertains to how clients’ perceptions and emotions can influence their investment decisions. He wants to ensure that he effectively manages this client's biases to maintain a well-diversified portfolio.

Which behavioral finance bias is James particularly concerned with in this scenario?