Sensation, Pain, and the Special Senses
How we sense the world
Sensory pathways
Sensory systems detect changes in the environment or inside the body. Receptors in the skin, muscles, eyes, ears, nose, and tongue convert information into nerve signals that travel to the brain for interpretation.
Examples of sensory systems
| Sense | Main job |
|---|---|
| Touch | Detects pressure, vibration, and texture |
| Pain | Warns of injury or harm |
| Vision | Detects light and forms images |
| Hearing | Detects sound |
| Balance | Detects head position and movement |
Pain is protective
Pain is not just unpleasant; it also helps protect the body by warning of injury or illness.
What do sensory receptors do?
Sensory receptors detect a stimulus and turn it into nerve signals.
Correct answer: Convert information into nerve signals
Name one special sense.
Vision is one of the special senses. Hearing and balance are also correct answers.
Correct answer: vision
Somatic vs special sensory input
Somatic sensation
- Includes touch, pain, temperature, and body position
- Comes from skin, muscles, and joints
Special senses
- Include vision, hearing, smell, taste, and balance
- Require specialized sense organs
Which symptom might suggest a sensory nerve problem?
Numbness can happen when sensory nerves are not carrying information normally.
Correct answer: Numbness in the foot
From stimulus to perception
Sensation begins with a physical stimulus, but perception happens when the brain interprets that signal. This is why the nervous system does not only detect information; it also makes sense of it.