Generative artificial intelligence (GenAI) is changing how consumers search for information, compare alternatives and make purchasing decisions. This conceptual paper examines how GenAI may reshape consumer choice in Nigeria without replacing human judgement. Drawing on the Technology Acceptance Model, the Stimulus-Organism-Response framework and a consumer autonomy perspective, the paper synthesizes literature on perceived usefulness, personalization, trust, perceived risk, AI literacy and consumer autonomy. It proposes that GenAI can influence need recognition, information search, consideration-set formation, evaluation of alternatives, purchase decisions and post-purchase interaction. Consideration-set formation is particularly important because AI recommendations may affect which alternatives consumers encounter and evaluate. Nigeria is treated as a contextual boundary condition because digital access, affordability, market availability, cultural diversity and digital capability shape AI-assisted choice. The paper distinguishes AI assistance from AI dependence and identifies implications for consumers, marketers and policymakers.