How do we perceive pain? specificity and pattern theory

HOW DO WE PERCEIVE PAIN? SPECIFICITY AND PATTERN THEORY

To answer this we have to go back to the major theories of pain perception.
Specificity theory
This proposes that free nerve endings or nociceptors — pain receptors — activated by mechanical deformation, chemical action or extremes of temperature produce pain impulses by A delta or C fibres. They are the thinnest of the nerve fibres, in the peripheral nerves that carry nerve signals back up to the spinal cord. These fibres then travel up the spinal cord in a complicated fashion rising to the thalamus — the great 'switching station' at the base of the brain. From the thalamus, the fibres join with others, finishing up in the grey matter of the brain's outer layer — the cortex, composed of billions of nerve'cells.
Pattern Theory
This describes pain as arising from non-specific receptors at the periphery. The stimulus enters the dorsal horn of the spinal cord causing an activation of a special nerve cell. This T cell is in the dorsal horn of the spinal cord.In turn, this sends the 'pain' signal to the brain stem and the cerebral cortex. In 1894, Dr A. Goldsheider, the pioneer German pain researcher, suggested that pain was perceived when the total number of signals exceeded a certain critical level. Below this, the sensation of touch, warmth or heat may be experienced.
According to his theory, the combination of the control of input and a central addition of these signals led to the development of a concept of pain involving perception- the sensation — and the reaction. Perception was considered a bodily process affected by specific nervous sensory and conduct mechanisms. 'Sensation' was described as a complex bodily process influenced by multiple psychological factors such as past experience and culture. But these two early theories did not explain certain types of pain where there was no particular stimulus. For example, an amputee's phantom limb pain and causalgia — the burning pain specifically caused by nerve damage, due classically to gunshot wounds.
The Pattern Theory explains only certain types of pain. But it was the forerunner of the modern theories of uncoated and coated nerve fibres and their role in pain.
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