<p>These kinds of research questions are interesting, but notoriously hard to investigate empirically, because:</p>

<ol>
<li>You need human subjects that are able to provide complex feedback, <em>i.e.</em>, you can't use invasive, long-term recordings in animals;</li>
<li>You need subjects to undergo long-term experiments, as your example indicates in the order of weeks, for <em>one single measurement</em>;</li>
<li>You need subjects that experience this regularly and frequently;</li>
<li>You need a way of faithfully time-stamping the exact moment of recall and somehow establish a procedure to grasp what's happening inside the brain against a variable, uncontrolled background.</li>
</ol>

<p>In essence, it's next to impossible to find out.</p>

<p>There is, however, a large body of literature around memory recall in general, including detailed imaging studies, <em>e.g.</em>, <a href="https://jamanetwork.com/journals/jamapsychiatry/fullarticle/205540" rel="noreferrer">Heckers <em>et al</em>. (1999)</a>, <a href="http://www.jneurosci.org/content/21/6/2186.short" rel="noreferrer">Hall <em>et al</em>. (2001)</a>, <a href="https://www.nature.com/articles/nature11028" rel="noreferrer">Liu <em>et al</em>. (2012)</a> and I'm sure there will be much overlap between spontaneous and deliberate memory recall.    </p>

<p><sub><strong>References</strong><br>
<strong>-</strong> <a href="https://jamanetwork.com/journals/jamapsychiatry/fullarticle/205540" rel="noreferrer">Heckers <em>et al</em>. <em>Arch Gen Psychiatry</em> (1999); <strong>56</strong>(12): 1117-23)</a><br>
<strong>-</strong> <a href="http://www.jneurosci.org/content/21/6/2186.short" rel="noreferrer">Hall <em>et al</em>. <em>J Neurosci</em> (2001); <strong>21</strong>(6): 2186-93</a><br>
<strong>-</strong> <a href="https://www.nature.com/articles/nature11028" rel="noreferrer">Liu <em>et al</em>. <em>Nature</em> (2012); <strong>484</strong>: 381–5</a></sub></p>

CC BY-SA 4.0
2018-09-12T15:58:49.387Z
This specific phenomenon has been studied more than I feel this answer reveals, but I'll have to spend some time to collect research if I'm going to post a reasonable counter answer.
Bryan Krause
CC BY-SA 4.0
2018-09-12T16:44:32.283Z
@BryanKrause I'll await your answer!
AliceD
CC BY-SA 4.0
2018-09-11T12:11:56.450Z
2018-09-11T12:11:56.450Z
AliceD
<p>What happens in the brain that allows you access to a memory previous unavailable?</p>

<p>For example I forgot the name of someone I've known for years. Two weeks later, without notice, "Diana" popped up. </p>

<p>Why was it not accessible when I found I couldn't remember?</p>

<p>What was the chemistry that occurred that allowed it to happen later?</p>

<p>(Secondarily, is this the same breakdown in dementia and alzheimer's? That is, a breakdown of the 'search memory' mechanism? Or is that the memories themselves are 'losing coherence.') </p>

<neuroscience><memory>
What happens in the brain that allows access to a previous unavailable memory?
Randy Zeitman
# What happens in the brain that allows access to a previous unavailable memory?

(Asked by: username_0 on 2018-09-11)

What happens in the brain that allows you access to a memory previous unavailable?

For example I forgot the name of someone I've known for years. Two weeks later, without notice, "Diana" popped up.

Why was it not accessible when I found I couldn't remember?

What was the chemistry that occurred that allowed it to happen later?

(Secondarily, is this the same breakdown in dementia and alzheimer's? That is, a breakdown of the 'search memory' mechanism? Or is that the memories themselves are 'losing coherence.')

**Tags:** neuroscience, memory


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## 1 answers

### Answer by username_1 on 2018-09-11. Score: 5

These kinds of research questions are interesting, but notoriously hard to investigate empirically, because:

1. You need human subjects that are able to provide complex feedback, *i.e.*, you can't use invasive, long-term recordings in animals;
2. You need subjects to undergo long-term experiments, as your example indicates in the order of weeks, for *one single measurement*;
3. You need subjects that experience this regularly and frequently;
4. You need a way of faithfully time-stamping the exact moment of recall and somehow establish a procedure to grasp what's happening inside the brain against a variable, uncontrolled background.

In essence, it's next to impossible to find out.

There is, however, a large body of literature around memory recall in general, including detailed imaging studies, *e.g.*, [Heckers *et al*. (1999)](https://jamanetwork.com/journals/jamapsychiatry/fullarticle/205540), [Hall *et al*. (2001)](http://www.jneurosci.org/content/21/6/2186.short), [Liu *et al*. (2012)](https://www.nature.com/articles/nature11028) and I'm sure there will be much overlap between spontaneous and deliberate memory recall.

**References**  
**-** [Heckers *et al*. *Arch Gen Psychiatry* (1999); **56**(12): 1117-23)](https://jamanetwork.com/journals/jamapsychiatry/fullarticle/205540)  
**-** [Hall *et al*. *J Neurosci* (2001); **21**(6): 2186-93](http://www.jneurosci.org/content/21/6/2186.short)  
**-** [Liu *et al*. *Nature* (2012); **484**: 381–5](https://www.nature.com/articles/nature11028)

> **Comments:**
> **username_2**: This specific phenomenon has been studied more than I feel this answer reveals, but I'll have to spend some time to collect research if I'm going to post a reasonable counter answer.  
> **username_1**: @BryanKrause I'll await your answer!  

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