Inclusion Criteria:  informed consent  Exclusion Criteria:  Healthy participants:  Neurological diseases Pre-diagnosed dysphagia Percutaneous endoscopic gastrostomy (PEG) tube Head and neck tumours Chemo- and/or radiotherapy in the head and neck area Reflux disease Chronic obstructive pulmonary disease (COPD) Previous surgeries on the cervical spine or thyroid gland Vocal cord paresis  Geriatric patients Neurologic diseases Stroke patients Head and neck tumours Chemo- and/or radiotherapy in the head and neck area Reflux disease COPD Previous surgeries on the cervical spine or thyroid gland Vocal cord paresis Neurologic patients without stroke Head and neck tumours (except of intracranial tumors= Chemo- and/or radiotherapy in the head and neck area Reflux disease COPD Previous surgeries on the cervical spine or thyroid gland Vocal cord paresis