Some embodiments of the present disclosure are directed to methods, systems and probe devices for detecting EMG activity. In some embodiments, such methods, systems and devices are used in aiding the diagnosis of Obstruction Sleep Apnea (OSA). In some embodiments, a probe is provided and comprises an elongated member configured with a size and shape for placement adjacent at least one of the soft palate and pharyngeal wall of the patient after insertion of the probe into the patient. The probe may also include at least one sensor configured to sense at least EMG activity of muscle layers of at least one of the soft palate and pharyngeal wall and output sensor signals corresponding thereto.