The sensory processors are what you call your "5 senses" typically. These are the 5 main senses that most people are aware of when it comes to concious sensory input. The main 5 you've heard of are touch, taste, smell, see and hear I'm quite sure.
These are you main senses that you're brain and nervous system are always using to gather and download data for you. Anytime you touch something or something touches you, that is new data being analyzed on an unconcious and subconscious level. Perhaps you are familiar with the sensitivity or the sensation of that touch, in which case you may percieve it as pleasant or unpleasant based on previous experiences.
But what about these other 3 senses that contribute to the 8 sensory processors?
First you have the Vestibular System or Processor. This pertains to your inner ear and your "balancing." This system is responsible for providing your brain with the information about motion, head position and spatial orientation. It is heavily with the motor functions of balance and allowing you to maintain posture as well as stability in your head and body through movement.
Second up you hace whats called proprioception. This is your concious and unconcious awareness of your body in and throughout movement. Proprioception is what gives cats and squirrels that ability to land on their feet almost always. They are acutely aware of their body in relation to the environment around them.
Third, interoception is the sense that provides you with the awareness of your internal body and function. Its the awareness of your hunger, your heartbeat, your digestion, your thirst, etc. This sense is both concious and unconcious at times.
These additional senses are all extremely important in your everyday life, and in understanding how you might better heal and listen to your own body. The sensory disorders may come when one or more of these 8 sensory processors doesn't work correctly. This is always an important part to know and consider when working with clients. It will set you aside as a better and more intuitive professional if you can help identify underlying issues or causes that may be contributing to their surface level pains or issues.