Links to interesting and useful resources:
Dr. Cooper's dissertation
Link to all of Dr. Cooper's works
Dr. Elaine Aron's web site "the Comfort Zone" where you are able to access her blog and a treasure trove of great resources like the research studies she conducted that first established sensory processing sensitivity as a separate personality trait. You can also find out about her appearance schedule and visit her store where you can purchase many of her books, including several that have been translated into different languages, audio books (for the auditory learners amongst us), and links to therapists who have taken her credentialing course.
Dr. Ted Zeff's web site. I am pleased to recommend Dr. Zeff for consultations in person, by phone or Skype. Ted has over 30 years counseling HSPs and HSCs (highly sensitive children). He is one of the few globally known experts in the area of HSPs. You can contact Dr. Zeff at the following link: http://drtedzeff.com/appointments.
Marie-Lise Schlappy, is actually a biologist (Dr. rer. Nat., Biology, Max-Planck institute for Marine Microbiology, Master in tropical marine ecology) who identifies as a high sensation seeking highly sensitive person and has created these two presentations asking the question "are all gifted individuals also highly sensitive people?"