The rapid adoption of artificial intelligence (AI) in higher education has transformed student learning behaviors and engagement patterns. While AI tools enhance efficiency and reduce cognitive load, concerns have emerged regarding cognitive offloading and potential dependency. This PRISMA-based systematic review synthesized findings from 16 peer-reviewed studies published between 2015 and 2026. Results indicate that students increasingly delegate cognitive tasks such as memory retrieval, idea generation, and problem-solving to AI systems. High reliance was associated with reduced analytical depth, automation bias, and lower metacognitive monitoring. However, structured and reflective use of AI was found to mitigate these negative effects. Memory outcomes varied depending on the level of cognitive engagement. The review also highlights a significant gap in the lack of standardized measures for AI dependency. Overall, AI functions as both a cognitive support tool and a potential source of dependency, emphasizing the need for balanced integration and further research on long-term cognitive effects.