Cannabis is becoming increasingly accepted across many parts of the world, often perceived as harmless or even beneficial.

But we thought: let’s take a closer look at what actually happens inside the brain when you smoke or consume cannabis.

Because behind the sense of calm or focus that many users describe lies a complex chain of neurological reactions that profoundly shape how we think, feel, and respond.

The main psychoactive compound, THC (tetrahydrocannabinol), interacts directly with the brain’s endocannabinoid system, a vast network that regulates mood, memory, coordination, reward, and decision-making. When THC binds to CB1 receptors, it disrupts normal neurotransmitter communication, changing how neurons send, receive, and process information.

This seemingly simple interaction triggers a cascade of changes across multiple brain areas:

• The hippocampus – crucial for learning and memory. THC interferes with the brain’s ability to form and retrieve new memories, which can lead to short-term memory loss and disorientation.

• The prefrontal cortex – responsible for planning, impulse control, and judgment. Under the influence of THC, activity here slows down, leading to delayed reactions and less accurate decision-making.

• The amygdala – central to emotion regulation and stress. Cannabis can overstimulate this area, which explains why some users feel relaxed, while others experience anxiety or even paranoia.

• The nucleus accumbens – part of the reward system. THC increases dopamine release, enhancing feelings of pleasure but also reinforcing the brain’s craving for repeated use.

  Beyond these neurological effects, cannabis also impacts the body. It can increase heart rate and blood pressure, slow motor coordination, and alter time perception – effects that might feel minor in everyday life but become critical in safety-sensitive contexts like driving, law enforcement, or industrial work.

  From a cognitive standpoint, cannabis subtly changes how the brain processes sensory input and plans movements. Reaction times lengthen, focus drifts, and attention narrows – small shifts that can have major real-world consequences when precision and alertness matter.

  At Sightic, we study these changes closely. Our AI-driven impairment detection technology analyzes micro-patterns in eye and facial behavior to detect early signs of substance influence, including cannabis.
  
  By combining neuroscience, real-world data, and computer vision, we’re building tools that make impairment detection more objective, accessible, and reliable.

  Understanding how substances like cannabis affect the brain isn’t just about science – it’s about creating safer roads, safer workplaces,  and  and smarter human-technology interaction.