<p>Yes.</p>

<p>One particular mechanism for reducing synaptic strength is called <a href="https://en.wikipedia.org/wiki/Long-term_depression" rel="nofollow noreferrer">long-term depression</a> (note: this terminology is not related to the mental health term depression). Much like the opposite process that strengthens synapses, certain firing patterns tend to weaken synapses.</p>

<p>Additionally, <a href="https://en.wikipedia.org/wiki/Synaptic_scaling" rel="nofollow noreferrer">synaptic scaling</a> is a homeostatic mechanism by which more excited cells become less excitable over time, including by reducing their response to inputs globally (this is also a particular category of long-term depression). If you keep re-strengthening certain synapses, and then scaling all of them down, the result over multiple iterations is that those synapses that don't get re-strengthened get weaker.</p>

<p>The <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3921176/" rel="nofollow noreferrer">synaptic homeostasis hypothesis</a> of sleep suggests that this process occurs during sleep and is a key reason why sleep is important (there are many other theories about sleep, however).</p>

CC BY-SA 4.0
2019-10-10T19:48:30.157Z
2019-10-10T20:00:33.993Z
2019-10-10T20:00:33.993Z
Bryan Krause
<p>Do we have any mechanism for deleting neuronal connections? </p>

<p>That is, if I learn a better version for doing something, I assume the brain will create a new neuronal connection, and we will use this connection. However, what happens to the old, non-used version? Does it fades away after a while? or is it enough to have a better, stronger connection to have the older version ignored, even if present?</p>

<neuroscience>
Mechanism for deleting old memories
Quora Feans
# Mechanism for deleting old memories

(Asked by: username_0 on 2019-10-10)

Do we have any mechanism for deleting neuronal connections?

That is, if I learn a better version for doing something, I assume the brain will create a new neuronal connection, and we will use this connection. However, what happens to the old, non-used version? Does it fades away after a while? or is it enough to have a better, stronger connection to have the older version ignored, even if present?

**Tags:** neuroscience


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## 1 answers

### Answer by username_1 on 2019-10-10. Score: 2

Yes.

One particular mechanism for reducing synaptic strength is called [long-term depression](https://en.wikipedia.org/wiki/Long-term_depression) (note: this terminology is not related to the mental health term depression). Much like the opposite process that strengthens synapses, certain firing patterns tend to weaken synapses.

Additionally, [synaptic scaling](https://en.wikipedia.org/wiki/Synaptic_scaling) is a homeostatic mechanism by which more excited cells become less excitable over time, including by reducing their response to inputs globally (this is also a particular category of long-term depression). If you keep re-strengthening certain synapses, and then scaling all of them down, the result over multiple iterations is that those synapses that don't get re-strengthened get weaker.

The [synaptic homeostasis hypothesis](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3921176/) of sleep suggests that this process occurs during sleep and is a key reason why sleep is important (there are many other theories about sleep, however).


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