Hypnosis often sounds like a hoax, something conjured for cheap laughs, where volunteers cluck like chickens on cue. But beneath the spectacle lies a practice far more nuanced and legitimate than its theatrical reputation suggests. Hypnosis is a real psychological phenomenon with scientific backing. Used for centuries to explore the mind, it is recognized as a legitimate tool in clinical psychology, helping with pain management and other conditions. 

Hypnosis is a state of consciousness where verbal suggestions can change how people think, feel, and behave. At its core, hypnosis relies on suggestions and concentration to shape people's perceptions and behaviors. The process of hypnosis begins with an induction phase where individuals focus all their attention on following guided instructions. This tends to lead to deep relaxation and mental absorption. During this relaxed state, verbal suggestions can influence both psychological and physical responses, such as reducing pain perception and creating hallucinations. 

This influence and thinking process type is called top-down processing, which allows suggestions to override standard cognitive and sensory processing. This demonstrates the brain's ability to modify experiences based on expectations and surroundings. Highly suggestible individuals are often more responsive to hypnosis because of the differences in cognitive control, and this reinforces the idea that hypnosis is an altered interaction between brain function, psychological mechanisms, and social influences.

Although there is much skepticism about the legitimacy of hypnosis, resting-state functional MRIs (fMRI), a neuroimaging technique that measures brain activity by detecting changes in blood flow which allow researchers to map functional connectivity in the brain, indicate that hypnosis can be associated with changes in brain connectivity, particularly in highly susceptible individuals. People are classified as highly susceptible to hypnosis when they show greater connectivity between their executive control and their salience network because these work in harmony to regulate attention and emotional responses. 

Additionally, hypnosis has been linked to decreased activity in the default mode network (DMN), which is responsible for aspects like thinking and mind-wandering. This suggests that hypnosis can create a state where people are more focused and absorbed in what they are doing, challenging the idea that hypnosis is just a made-up idea or social construct used in entertainment. By creating a focused state, the decreased activity supports the notion that hypnosis represents a unique altered state of consciousness.

These scientific studies have shown that during hypnosis, there is also reduced activity in the dorsal anterior cingulate cortex (dACC), a region involved in conflict monitoring and self-awareness. The dACC helps detect errors and regulate emotional responses, acting as a sort of "alarm system" for the brain. The decreased activity in the dACC is a possible explanation for the deep focus and suggestibility correlated with hypnotized individuals. As this happens, there is also increased connectivity between the dorsolateral prefrontal cortex (DLPFC) and the brain's insular cortex. This also suggests an enhancement in top-down sensory experience during hypnosis. 

Crucially, studies show that hypnosis can induce vivid hallucinations, which explains why some individuals report "seeing" or experiencing unreal stimuli under suggestion. Unlike voluntary mental imagery, these hypnotic hallucinations are automatic, vivid, and feel undeniably real, as they hijack the brain’s sensory systems. This phenomenon highlights how hypnosis blurs the line between internal and external reality. Far from a magic trick, hypnosis reshapes perception at a biological level, providing proof that the mind’s suggestibility is as real as the brain itself.