This chapter analyses the right to freedom of thought in the Chilean legal order, considering its various juristic dimensions. Though historically rooted in the nation’s foundational charters, it remains ambiguously defined within its legal system, primarily interpreted through the lenses of freedom of conscience and expression. This chapter argues that whilst the right to freedom of thought has not yet been explicitly enshrined in the Chilean Constitution, it has been implicitly incorporated through international human rights treaties; however, due to recent technological advances, a pressing re-evaluation has arisen. The 2021 Constitutional Reform Act innovatively protected brain activities by resorting to the right to mental integrity, introducing a paradigm shift in juridical safeguarding of cognitive freedoms. This development, however, presents new conceptual and systematic challenges. The chapter focuses on the historical evolution of the right to freedom of thought, judicial interpretations, and scholarly perspectives, mainly concentrating on the emerging category of ‘neurorights’. It examines the implications of the 2021 constitutional amendment and argues for a more precise recognition and theoretical development of the right in response to neurotechnological progress. The analysis underscores the necessity of unambiguously defining cognitive freedoms and freedom of thought to provide adequate legal protections in an era of rapid technological change.