Scientists have uncovered a surprisingly simple mechanism in the human brain that may act as a natural “dial” to help us tell the difference between what we imagine and what we perceive as real. The new study, published in Neuron on June 5, shines a light on fundamental brain processes that distinguish fact from fiction—a discovery with profound implications for understanding mental health conditions like schizophrenia, where this boundary can blur dangerously (Live Science).
Whether daydreaming on a Bangkok bus or focusing intently on a work presentation, our brains constantly process both real-world stimuli and flights of imagination. For Thai readers, this research probes a question close to home: how does the brain prevent confusion between the sound of a bustling soi and imagined memories of Songkran festivities? The answer, scientists now suggest, lies in the strength of signals in a region called the fusiform gyrus—an area crucial for recognizing faces and objects.
The breakthrough study, led by a neuroscientist from University College London, reveals that both real and imagined visuals activate the fusiform gyrus. However, the difference lies not in where the signal comes from, but how strong it is. During perception—when we see something “for real”—the activity spikes above a certain threshold. Below that level, the brain tends to classify the experience as just imagination. “The activity levels in [the fusiform gyrus] predicted whether or not you think something is real, irrespective of whether you see or imagine it,” explained the lead author in an interview with Live Science.
To reach these conclusions, the research team conducted experiments involving 26 volunteers. Participants looked for subtle diagonal lines within visual “noise”, like TV static, while inside a functional MRI (fMRI) scanner. Sometimes the lines genuinely appeared; other times, they were asked just to imagine them. Participants reported not only whether they saw the lines, but also how vividly the images appeared in their minds.
Crucially, when study participants imagined the same lines they expected to see onscreen, they were more likely to claim they saw real lines even when they weren’t actually present. This effect highlights how vivid imagination can trick the mind into crossing the threshold of reality—a finding with echoes in Thai folklore about spirits and omens, where belief often seems as powerful as perception.
The study’s brain scans showed that “activation during imagination [alone] is not strong enough to cross this threshold,” according to the research leader. But when it does—by accident, repetition, or perhaps due to individual susceptibility—the door opens to confusing fiction with fact. This may help explain the neurological roots of hallucinations or false memories.
Another brain area, the anterior insula, also lit up in tandem with rising activity in the fusiform gyrus. This region, nestled within the prefrontal cortex, is important for decision-making and self-awareness. The research team suggests the anterior insula may function as a ‘reader’ that interprets the fusiform’s reality ‘signal’—though the details of their connection remain unclear.
The findings are especially relevant to mental health, a major concern in Thailand and globally. Individuals with schizophrenia and similar disorders may experience breakdowns in their ability to distinguish imagination from reality. Commenting on the study, a neuroscientist from the University of the Sunshine Coast, who was not involved in the research, described the results as “a remarkably simple explanation for how we distinguish reality from mental imagery.” He added, “It helps explain how reality monitoring can fail, and lays the foundation for understanding complex experiences like hallucinations.”
The research has some limitations—the visual tasks were artificial and simple, involving only lines and static, rather than faces, animals, or everyday Thai objects. The research team acknowledges the need for follow-up studies using richer stimuli and real-world experiences, which typically also involve sounds, touch, or logical sequences—factors central to traditional Thai storytelling and Buddhist meditation practices. As the first author notes, “We are now developing paradigms to include more complicated stimuli like objects, faces or animals.” Other questions remain, such as whether techniques like brain stimulation could artificially nudge perceptions past the reality threshold.
For Thai readers, the implications stretch from medicine to culture. In a society where dreams, ghosts, and spiritual beliefs intermingle with daily life, the discovery of a biological “reality dial” offers a modern explanation for ancient questions. Practical applications may one day include improved diagnosis and treatment for Thai patients with psychosis, as well as better understanding of how practices like guided meditation train the mind to recognize the boundary between thought and experience (Neuron, 2025).
Looking ahead, the research community hopes to test these mechanisms in more naturalistic tasks and in clinical populations. For instance, Bangkok’s leading mental health institutes or academic hospitals may soon join international efforts to map the brain circuits that help—or hinder—reality monitoring. This could ultimately lead to new therapies for psychosis or dementia, which are significant health challenges in Thailand’s aging population (World Health Organization).
There may also be lessons for education. Teachers can help young students distinguish between fantasy and reality by encouraging observation, critical thinking, and mindfulness—drawing on traditional Thai values of discernment and ‘sati’ (awareness). Families concerned about young people’s screen time or online games can use these findings to talk about the power—and limits—of imagination.
As a call to action, Thai readers are encouraged to cultivate mindful awareness. When you notice vivid images in your mind—whether joyful or distressing—pause, breathe, and check for tangible signs. Recognize that the brain, for all its complexity, sometimes blurs the boundary between inside and outside. Understanding this natural “dial” can both strengthen mental resilience and foster empathy for those who struggle to tell imagination from reality. For families in Thailand and beyond, this research offers a fresh perspective on age-old debates about dreams, reality, and the ever-surprising powers of the human mind.
For more information, see the original study as reported by Live Science and published in Neuron.