Another kind of relativity.
https://en.majalla.com/node/296151/science-technology/insight-how-brain-tells-time-brings-einsteins-theory-relativity-down

"The stronger the gravitational field, the more the dilation slows time. And so, time passes more slowly near massive objects such as planets, stars, or black holes compared to regions with weaker gravitational fields.

But just as gravity affects time, our own neural circuits can dilate or contract our own experience of time, according to a recent study published in the journal Nature Neuroscience.

Looking closer to home than his studies of the universe, Einstein also referred to different human perceptions of time, saying: "When you sit on a hot stove for a minute you think it's two hours. When you sit with a nice girl for two hours you think it's only a minute."

Much human and animal behaviour is time-based. People and animals alike must extract chronological signals and structures from the environment to learn to anticipate events, understand the relationships between actions and outcomes, and estimate time – implicitly or explicitly – to plan, sequence, and coordinate action.
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In the new research – as revealed in Nature Neuroscience – scientists distorted the way mice perceive time by artificially slowing down patterns of neural activity, then accelerating them. The change in the animals' judgement of time provided the most convincing causal evidence yet that the behaviour of the brain directs an internal clock.

The idea of this kind of moment-by-moment biological timekeeping – involving internal mechanisms or processes within organisms – is relatively recent.
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In the new study, the researchers trained mice to distinguish between different time periods. They found that activity in the striatum, a deep brain region, followed predictable patterns that changed at different speeds.

This means that neural activity within the striatum is associated with time perception. Observing patterns suggest that the rate at which activity develops in that brain region is related to mice's self-experience over time."
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Einstein was ahead of the neuroscientists:
"When you sit on a hot stove for a minute you think it's two hours. When you sit with a nice girl for two hours you think it's only a minute."

Sensory inputs cause emotion mediated time dilation or contraction. Is time perception change related to and/or necessary for learning? In the above case, both sitting on a hot stove and sitting would be easily remembered. The question is at what points along the faster time/slower time curve that different kinds of learning could be optimized.