How can the level of pain you feel very if a stimulus causes an all-or-none response?

http://wiki.answers.com/Q/How_can_the_level_of_pain_you_feel_vary_if_a_stimulus_causes_an_all-or-none_response

thanks a bunch

The level of pain you feel can vary even if a stimulus causes an all-or-none response because pain perception involves complex processes that go beyond the initial response of nerve cells. While the initial sensory information about a painful stimulus is indeed transmitted in an all-or-none fashion by nerve fibers called nociceptors, the perception and interpretation of this information by the brain can be influenced by various factors, resulting in different pain experiences.

Here are some reasons why the level of pain can vary:

1. Sensory Modulation: After the initial nociceptor response, the transmission of pain signals can be modulated by other sensory input. For example, if you accidentally stub your toe while listening to your favorite song, your brain may prioritize the emotional response from the music over the pain, leading to a reduced perception of pain.

2. Central Processing: The brain receives and processes the incoming pain signals. Higher brain regions, such as the somatosensory cortex and the limbic system, play a role in interpreting and modulating pain perception. Factors like attention, emotional state, and previous experiences can all influence how the brain processes pain signals, ultimately affecting the level of perceived pain.

3. Psychological Factors: Individual psychological factors, including anxiety, stress, and fear, can contribute to the experience of pain. These factors can amplify or diminish the pain perception, even if the initial stimulus is the same.

4. Context and Expectations: The context in which pain occurs and individual expectations can also shape pain perception. For example, anticipation of pain during a medical procedure might intensify the pain experience, whereas distraction or relaxation techniques might reduce the perception of pain.

It's important to note that pain is a subjective experience, and everyone's perception of pain can differ based on various factors.