The acupressure points that are located behind the ear have influence along the gall bladder and triple warmer meridians. They can be a bit difficult to find if you don't know what you're looking for. However, with a little study and a good diagram, anyone can find them.
Place a finger directly behind the ear, just below the curve of the top of the outer ear. You will feel a ridge of bone on the skull. The pressure point is directly above this line, on the temporal bone. The points gall bladder 10 and triple warmer 19 are very close to one another. The triple warmer point is located directly on the mastoid bone, and the gall bladder point is in the temporal region just above the mastoid bone. The mastoid bone can be located by feeling for a bony protrusion just behind the ear. These pressure points help to relieve problems including anxiety, headache, hearing loss, tinnitus and neck tension.
Run your finger down behind the ear. Stop at a point just above the ear lobe. The points GB 11 and TW 18 are here. GB 11 is located in the temporal region, and the TW 18 point is directly on the mastoid bone. Place gentle pressure on these points and feel for knots, or a sensation of tension release. These acupressure points help to relieve headache, deafness, tinnitus, pain in the ear and eye, and tension in the neck.
Consult a text like Gray's Anatomy if you encounter any difficulty in telling the temporal area apart from the mastoid bone. Excellent scans of the illustrations from Gray's Anatomy are available for free online viewing.
Consult a reference book on acupuncture or acupressure to get a clearer idea of the location of the pressure points. An excellent reference is "A Manual of Acupuncture" by Peter Deadman and Kevin Baker. Most books and charts on acupressure omit these particular points; however, you may wish to purchase one anyway, to find instructions on how to apply acupressure properly.
Acupuncture and acupressure points are interchangeable.