Time perception and Cannabis: why can minutes feel like hours?

You put on a song and it feels like the track lasts twice as long. A conversation that started five minutes ago seems to have been going on for half an hour. Then you check the time, convinced it must be really late, only to discover that the hands of the clock have barely moved. Your time perception is altered, as though minutes and hours have lost their usual proportions.

The feeling that time is stretching is one of the most iconic and commonly reported effects associated with THC. But what exactly is happening in our heads? Behind this “slowdown” lies a fascinating cognitive mechanism: our brains do not measure every second in the same way and, more importantly, they do not have a single digital “internal clock” keeping track of time.

How does the brain measure time?

Our perception of time changes depending on how we experience it.

• If we are consciously waiting for 30 seconds to pass, all our attention is focused on the duration of the wait.
• If, on the other hand, we reconstruct the duration of a past event after the fact, we rely on memory: the more details and memories we can retrieve, the longer that period will seem.

Studies on THC focus on the first case: the active estimation of short time intervals. Here, the process depends on attention, working memory and the ability to continuously update our mental count.

To explain this phenomenon, researchers use the internal clock model: during a given interval, the brain accumulates a series of “pulses” or signals. The more signals it registers, the longer the perceived duration becomes. If this “counter” speeds up, 10 real seconds may feel twice as long. There is no actual stopwatch inside the brain, but the model is extremely useful for describing how we perceive the passing of time.

Estimating vs producing an interval: two sides of the same coin

In laboratory tests of time perception, researchers use two different types of task:

1. Estimation task: you are shown a stimulus, such as a light or a sound, and asked to estimate how many seconds it lasted.
2. Time-production task: you are asked to stop a stimulus after a specific amount of time—for example, “stop the light when you think 10 seconds have passed.”

If your perception of time is “running fast,” you tend to overestimate the actual duration in the first task. In the second, however, you stop the timer too early, convinced that the required amount of time has already passed.

They may seem like opposite errors, but they stem from exactly the same mechanism: an internal clock running faster than usual.

What does the clinical study on THC tell us?

To measure this effect scientifically, R. Andrew Sewell, Ashley Schnakenberg and the team led by Deepak C. D’Souza enrolled 44 participants in randomized, double-blind, placebo-controlled crossover studies.

Participants were given different doses of pure THC intravenously, ranging from 0.015 to 0.05 mg/kg, and completed visual tasks involving the estimation and production of intervals lasting a matter of seconds.

The results? Under the effects of THC, participants judged time intervals to be significantly longer than they actually were and tended to stop the time-production tasks early. These findings were fully consistent with the idea of an accelerated internal clock.

One crucial detail: the effect did not increase in proportion to the dose. Higher doses of THC did not necessarily produce stronger distortions in time perception. This challenges the simplistic formula “more THC = time moving increasingly slowly.”

Frequent vs occasional users: who feels the effect more?

This is where the research produced a surprising result: the distortion of time perception emerged almost exclusively among occasional users and non-users.

Frequent users showed no significant differences between THC and placebo in the time-perception tasks. According to the researchers, frequent and repeated exposure to the substance may have produced a form of tolerance or reduced sensitivity to this particular acute effect.

Before THC was administered, however, both groups achieved comparable results. This suggests that frequent use does not permanently alter time perception; it simply changes the acute response to the substance.

The key role of attention and memory

A period of time always seems longer when we focus intensely on it. This happens in everyday life too: waiting for a late bus can make minutes feel endless, while three hours can fly by during an enjoyable evening without us even noticing.

THC changes how our attention is distributed, affects working memory and alters the importance we assign to individual stimuli. During an experience, very small details can take up a disproportionate amount of mental space. The brain may therefore process an interval lasting only a few seconds as though it were packed with events, stretching our perception of its duration.

So, what is the takeaway?

Science confirms that, under the experimental conditions studied, THC alters how we measure very short intervals of time. But calculating exactly how long this distortion will last for any given person is impossible. Saying that “five minutes feel like twenty” remains a great metaphor for describing an iconic and, above all, unique sensation.

if you’re curious which are the cities of cannabis, learn about them in our article!