Which of the following statements is true of trigger points?

The statement indicating that trigger points are a source of constant deep pain and can produce central excitatory effects is correct because it reflects the understanding of how myofascial trigger points operate. Trigger points are hyperirritable spots within skeletal muscle that are palpable and can cause referred pain, which may be experienced as a deep, aching sensation. This pain can also evoke a response from the central nervous system, resulting in central sensitization, where the nervous system becomes increasingly responsive to stimulation, amplifying pain perception.

Additionally, trigger points can lead to muscle dysfunction and may also influence motor control, which further supports their role in the development of chronic pain conditions. This characteristic of generating deep-seated pain can thus influence overall muscle dynamics and pain perception, making it a significant area of focus in pain management and rehabilitation.

In contrast, the other statements do not capture the complete nature of trigger points effectively. For instance, while the exact nature of trigger points can be understood to some degree, research is still ongoing, and they do not have a universally accepted definition, which challenges the notion that their nature is well established. The reduction in metabolic demand and blood flow may occur in relation to trigger points, but this does not adequately define their primary characteristics. Lastly, although