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It is well established that middle ear transmission is influenced by posture. This phenomenon is associated with variations in intracranial pressure (ICP) when a subject transitions from an upright to a supine position. Typically, this transition leads to an increase in ICP. The resulting rise in endocranial fluid pressure alters middle ear (ME) impedance, generally producing an increase in stiffness, which is linked to the imaginary component of the impedance. These impedance variations also affect distortion product otoacoustic emission (DPOAE) phase. This study is aimed at optimizing joint OAE- an ME-based techniques to assess ICP increases under microgravity conditions. DPOAEs were recorded in both upright and supine positions. Additionally, ME energy reflectance, along with the real and imaginary components of impedance, was measured. Typically, the results align with theoretical expectations, but several counterexamples are observed, which need explanation to enhance the diagnostic power of the proposed technique.Overall, joint OAE-based and ME-based ICP estimation demonstrate potential as a benchmark technique for monitoring intracranial pressure changes in space environments, where such non-invasive and reliable physiological monitoring is essential during prolonged missions in microgravity conditions. Further investigations are needed to refine methodological accuracy and broaden clinical applicability across diverse populations and conditions.