<ul>
<li><p>PET (positron emission tomography) will measure glucose consumption, e.g. <a href="https://www.ncbi.nlm.nih.gov/pubmed/2147116" rel="nofollow noreferrer">https://www.ncbi.nlm.nih.gov/pubmed/2147116</a></p></li>
<li><p>fMRI will measure changes in blood flow, or more precisely measuring the blood-oxygen-level dependent (BOLD) response. <a href="https://www.nature.com/scitable/blog/brain-metrics/what_does_fmri_measure" rel="nofollow noreferrer">https://www.nature.com/scitable/blog/brain-metrics/what_does_fmri_measure</a></p></li>
</ul>

<p>Note that I'm being a bit simplistic here, as with PET you can measure a lot of different things (like activation of circuits depending on specific neurotransmitters) depending on the tracer used. Here's a table from the book <em>PET and SPECT in Neurology</em>:</p>

<p><a href="https://i.sstatic.net/AeUqB.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/AeUqB.png" alt="enter image description here"></a></p>

<p>The downside is that PET has <a href="http://www.scholarpedia.org/article/Functional_imaging" rel="nofollow noreferrer">lower spatial resolution than fMRI</a> and substantially lower temporal resolution, meaning chnages over time are hard to pick up with PET. If you care about quick changes, then MEG or EEG are the fastest, but you have solve a difficult <a href="https://link.springer.com/referenceworkentry/10.1007/978-1-4614-7320-6_529-1" rel="nofollow noreferrer">inverse problem</a> to figure out where the changes came from, which requires making quite a few assumptions to get a (unique) solution.</p>

<p>And let me add (for infotainment purposes) <a href="http://blogs.discovermagazine.com/neuroskeptic/2013/08/30/fmri-killed-the-radiotracer/" rel="nofollow noreferrer">"[f]MRI Killed The Radiotracer"</a>.</p>

CC BY-SA 3.0
2017-12-24T12:41:52.030Z
Just out of additional curiosity. Are you aware that any such diagnosis equipment is available for large animals such as elephants?
jjack
CC BY-SA 3.0
2017-12-24T13:15:26.490Z
@jjack: I'm not sure. It would certainly require specialized equipment to scan live elephants because the usual scanners made for humans are too small. I did find one paper in which the brain of a recently deceased elephant went under MRI: http://allmanlab.caltech.edu/PDFs/Hakeem2005.pdf
got trolled too much this week
CC BY-SA 3.0
2017-12-25T13:31:53.513Z
@Fizz I haven't read the paper, but how can a dead brain function?
Ooker
CC BY-SA 3.0
2017-12-25T14:01:31.787Z
@Ooker: MRI (unlike **f**MRI) does not measure function, only anatomy.
got trolled too much this week
CC BY-SA 3.0
2017-12-24T12:36:53.197Z
2017-12-25T14:06:44.370Z
2017-12-25T14:06:44.370Z
got trolled too much this week
<p>The question goes back to <a href="https://twitter.com/JuliaHass/status/943517409322913795" rel="nofollow noreferrer">this tweet</a>:</p>
<blockquote>
<p>Julia‏ @JuliaHass</p>
<p>I just learned that elephants think humans are cute the way humans think puppies are cute (the same part of the brain lights up when they see us) so pack it in, nothing else this pure and good is happening today.</p>
</blockquote>
<p>The <a href="https://skeptics.stackexchange.com/questions/40275/do-elephants-see-humans-the-same-way-humans-see-puppies">skeptics stack exchange post about the tweet refers to elephants</a>, but I'm interested in a general answer.</p>

<neuroscience><neurophysiology><neurology><brain><experimental-neuroscience>
Which possible methods can be used to determine if a certain part of the brain is active?
jjack
# Which possible methods can be used to determine if a certain part of the brain is active?

(Asked by: username_0 on 2017-12-24)

The question goes back to [this tweet](https://twitter.com/JuliaHass/status/943517409322913795):

> Julia‏ @JuliaHass
>
> I just learned that elephants think humans are cute the way humans think puppies are cute (the same part of the brain lights up when they see us) so pack it in, nothing else this pure and good is happening today.

The [skeptics stack exchange post about the tweet refers to elephants](https://skeptics.stackexchange.com/questions/40275/do-elephants-see-humans-the-same-way-humans-see-puppies), but I'm interested in a general answer.

**Tags:** neuroscience, neurophysiology, neurology, brain, experimental-neuroscience


---

## 1 answers

### Answer by username_1 on 2017-12-24. Score: 1 | Accepted answer

* PET (positron emission tomography) will measure glucose consumption, e.g. <https://www.ncbi.nlm.nih.gov/pubmed/2147116>
* fMRI will measure changes in blood flow, or more precisely measuring the blood-oxygen-level dependent (BOLD) response. <https://www.nature.com/scitable/blog/brain-metrics/what_does_fmri_measure>

Note that I'm being a bit simplistic here, as with PET you can measure a lot of different things (like activation of circuits depending on specific neurotransmitters) depending on the tracer used. Here's a table from the book *PET and SPECT in Neurology*:

[![enter image description here](https://i.sstatic.net/AeUqB.png)](https://i.sstatic.net/AeUqB.png)

The downside is that PET has [lower spatial resolution than fMRI](http://www.scholarpedia.org/article/Functional_imaging) and substantially lower temporal resolution, meaning chnages over time are hard to pick up with PET. If you care about quick changes, then MEG or EEG are the fastest, but you have solve a difficult [inverse problem](https://link.springer.com/referenceworkentry/10.1007/978-1-4614-7320-6_529-1) to figure out where the changes came from, which requires making quite a few assumptions to get a (unique) solution.

And let me add (for infotainment purposes) ["[f]MRI Killed The Radiotracer"](http://blogs.discovermagazine.com/neuroskeptic/2013/08/30/fmri-killed-the-radiotracer/).

> **Comments:**
> **username_0**: Just out of additional curiosity. Are you aware that any such diagnosis equipment is available for large animals such as elephants?  
> **username_1**: @username_0: I'm not sure. It would certainly require specialized equipment to scan live elephants because the usual scanners made for humans are too small. I did find one paper in which the brain of a recently deceased elephant went under MRI: http://allmanlab.caltech.edu/PDFs/Hakeem2005.pdf  
> **username_2**: @Fizz I haven't read the paper, but how can a dead brain function?  
> **username_1**: @username_2: MRI (unlike **f**MRI) does not measure function, only anatomy.  

---

