Implications of spiritual experiences to the understanding of mind-brain relationship

► The understanding of the mind-brain relationship (MBR) has been one of greatest scientific/philosophical challenges. ► Spiritual experiences (SE) often involve altered states of consciousness and reports of anomalous experiences that deserve rigorous investigation. ► We argue that SE may provide the much needed enlargement of the empirical basis for advancing the understanding of the MBR. ► We review recent scientific investigations on SE and discuss their implications to the understanding of human mind and MBR. ► Scientifific investigations of several types of SE have provided thought-provoking evidence against materialistic reductionist views of mind.