Unit 3 Psychology
Area of Study 1: How does the nervous system enable psychological functioning?
Key knowledge: Dot point 2
“The distinction between conscious and unconscious responses by the nervous system to sensory stimuli, including the role of the spinal reflex.”
Conscious and Unconscious Responses
The brain and nervous system are responsible for responses the body makes to both internal and external stimuli. These responses require varying degrees of awareness and attention.
When responses rely on a person paying attention and being aware of their actions, it is known as a conscious response.
Conscious response: a reaction to sensory stimuli that involves awareness.
Conscious responses are voluntary and include things such as walking, talking, eating, reading, choosing what clothes to wear, etc.
Conscious responses involve the brain and the somatic nervous system.
When a response does not rely on a person paying attention and being aware of their actions, it is known as an unconscious response.
Unconscious response: a reaction to sensory stimuli that does not involve awareness.
Unconscious responses are involuntary and include things such as the secretion of hormones (for example to regulate the sleep-wake cycle), breathing, digestion, perspiration and reflexes.
Unconscious responses involve the autonomic nervous system.
All actions of the ANS are reflexive, as they do not require a direct command from the brain. There are also another set of reflexes within the body, which are designed to aid survival.
Reflex: an automatic involuntary behaviour that does not require prior experience and occurs in the same way each time.
One reflex that is very important in survival and harm minimisation is the spinal reflex.
Spinal reflex: an unconscious, involuntary and automatically occurring response to certain stimuli without any involvement of the brain.
The spinal reflex and other reflexes are commonly known as a reflex arc. This is due to the way the reflex performs. The sensory information is sent to the spinal cord and is immediately reflected back via the motor neurons to the starting point. This creates an ‘arc.’
How the spinal reflex works
1. Sensory neurons detect the stimuli and send the information to the spinal cord.
2. The interneurons in the spinal cord receive the sensory information and connect with the motor neurons to initiate a response.
3. The motor neurons carry the response back to the appropriate body part.
4. The reflex action occurs.
5. While the reflex is occurring the sensory information has travelled from the spinal cord to the brain for processing.
6. The brain processes the sensory information for the sensation to be ‘felt.’
*Reflexes videos
**Psych Book – Activity 3
***Student Activity Manual – 1.4
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