The present invention provides improved adjustable thickness pillows designed to be placed under the head and neck of a person lying in a supine and/or side-lying position. Such devices are useful for maintaining or improving cervical and/or thoracic spinal curvature and/or alignment and for reducing pain associated with ailments of the neck or cervical vertebrae. Also provided are methods of improving cervical spinal alignment and for treating or ameliorating ailments of the neck or cervical vertebrae.
