In psychoneuroendocrinology there's a scarcity of knowledge of hypothalamic-pituitary-thyroid axis (HPT) in relation to bipolar disorder (BD) and neuropsychological functions. The aim of this study is to review the current state of the following issues: (1) neuropsychological dysfunctions in BD, as well as their hypothetic aetiology; (2) response of HPT in each phase of BD, and, finally, (3) connection between alterations in HPT and neuropsychological deficits.