Haptic or haptics is becoming an umbrella term, which is used to refer to all forms of touch and touch related senses and perceptions.

• Pressure
• Pain — Nociception
• Temperature — Thermoception
• Touch
• Proprioception
• Equilibrioception — Balance, movement, gravity(up/down)
• Muscle sensors, e.g.,
  • Velocity (1a afferents)
  • Force
  • Position (II afferents)
  
  

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Sources and Resources

• Cognitive scientists discover new perceptual illusion
• Tactile and haptic perceptual organization
• LUCS Haptic Hand III An Anthropomorphic Robot Hand with Proprioception
• Comparison of Skin Stretch and Vibrotactile Stimulation for Feedback of Proprioceptive Information
• VESTIBULAR, PROPRIOCEPTIVE, AND HAPTIC CONTRIBUTIONS TO SPATIAL ORIENTATION
  
  
• Diverse and complex muscle spindle afferent firing properties emerge from multiscale muscle mechanics
• The Neuropnysiology of Tone: The Role of the Muscle Spindle and the Stretch Reflex
• A muscle spindle model for primary afferent firing based on a simulation of intrafusal mechanical events
  Part of paper (see index)
• Force encoding in muscle spindles during stretch of passive muscle
• Muscle spindles
• Human Muscle Spindle Sensitivity Reflects the Balance of Activity between Antagonistic Muscles
• An allometric analysis of the number of muscle spindles in mammalian skeletal muscles
• Changes in muscle spindle firing in response to length changes of neighboring muscles
• Functional properties of human muscle spindles
• New functions for the proprioceptive system in skeletal biology