Final answer:
Neuromodulators, like BOTOX®, block nerve impulses to temporarily paralyze muscles, reducing the appearance of wrinkles.
Step-by-step explanation:
Injected toxins that block nerve impulses and temporarily paralyze muscles that cause facial wrinkles are called neuromodulators. These substances, such as BOTOX® (the brand name for botulinum toxin), work by inhibiting the release of the neurotransmitter acetylcholine at the neuromuscular junction, leading to the temporary relaxation of muscles. This effect diminishes the appearance of wrinkles and can also be used for medical purposes, such as treating excessive muscle contraction in conditions like cervical dystonia, cerebral palsy, multiple sclerosis, and Parkinson's disease.