Editing Binding problem (section)

=== Experimental work on the biological basis of binding ===
==== fMRI work ====
Stoll and colleagues conducted an fMRI experiment to see whether participants would view a dynamic bistable stimulus globally or locally.<ref name=":0" /> Responses in lower visual cortical regions were suppressed when participants viewed the stimulus globally. However, if global perception was without shape grouping, higher cortical regions were suppressed. This experiment shows that higher order cortex is important in perceptual grouping.

Grassi and colleagues used three different motion stimuli to investigate scene segmentation or how meaningful entities are grouped together and separated from other entities in a scene.<ref name=":1" /> Across all stimuli, scene segmentation was associated with increased activity in the posterior parietal cortex and decreased activity in lower visual areas. This suggests that the posterior parietal cortex is important for viewing an integrated whole.

==== EEG work ====
Mersad and colleagues used an EEG frequency tagging technique to differentiate between brain activity for the integrated whole object and brain activity for parts of the object.<ref>{{Cite journal|last1=Mersad|first1=Karima|last2=Caristan|first2=Céline|date=2021-09-17|title=Blending into the Crowd: Electrophysiological Evidence of Gestalt Perception of a Human Dyad|journal=Neuropsychologia|volume=160|pages=107967|doi=10.1016/j.neuropsychologia.2021.107967|issn=1873-3514|pmid=34303717|s2cid=236183221|doi-access=free}}</ref> The results showed that the visual system binds two humans in close proximity as part of an integrated whole. These results are consistent with evolutionary theories that face-to-face bodies are one of the earliest representations of social interaction.<ref name=":2" /> It also supports other experimental work showing that body-selective visual areas respond more strongly to facing bodies.<ref>{{Cite journal|last1=Abassi|first1=Etienne|last2=Papeo|first2=Liuba|date=2020-01-22|title=The Representation of Two-Body Shapes in the Human Visual Cortex|journal=The Journal of Neuroscience|volume=40|issue=4|pages=852–863|doi=10.1523/JNEUROSCI.1378-19.2019|issn=1529-2401|pmc=6975292|pmid=31801812}}</ref>

==== Electron tunneling ====
Experiments have shown that ferritin and neuromelanin in fixed human ''substantia nigra pars compacta'' (SNc) tissue are able to support widespread electron tunneling.<ref>{{Cite journal|last=Rourk|first=Christopher J.|date=May 2019|title=Indication of quantum mechanical electron transport in human substantia nigra tissue from conductive atomic force microscopy analysis|url=http://dx.doi.org/10.1016/j.biosystems.2019.02.003|journal=Biosystems|volume=179|pages=30–38|doi=10.1016/j.biosystems.2019.02.003|pmid=30826349|bibcode=2019BiSys.179...30R|s2cid=73509918|issn=0303-2647|url-access=subscription}}</ref> Further experiments have shown that ferritin structures similar to ones found in SNc tissue are able to conduct electrons over distances as great as 80 microns, and that they behave in accordance with Coulomb blockade theory to perform a switching or routing function.<ref>{{Cite journal|last1=Rourk|first1=Christopher|last2=Huang|first2=Yunbo|last3=Chen|first3=Minjing|last4=Shen|first4=Cai|date=2021-08-12|title=Indication of Strongly Correlated Electron Transport and Mott Insulator in Disordered Multilayer Ferritin Structures (DMFS)|journal=Materials|volume=14|issue=16|pages=4527|doi=10.3390/ma14164527|pmid=34443050|pmc=8399281|bibcode=2021Mate...14.4527R|issn=1996-1944|doi-access=free}}</ref><ref>{{Cite journal|last1=Labra-Muñoz|first1=Jacqueline A.|last2=de Reuver|first2=Arie|last3=Koeleman|first3=Friso|last4=Huber|first4=Martina|last5=van der Zant|first5=Herre S. J.|date=2022-05-15|title=Ferritin-Based Single-Electron Devices|journal=Biomolecules|volume=12|issue=5|pages=705|doi=10.3390/biom12050705|pmid=35625632|pmc=9138424|issn=2218-273X|doi-access=free}}</ref> Both of these observations are consistent with earlier predictions that are part of a hypothesis that ferritin and neuromelanin can provide a binding mechanism associated with an action selection mechanism,<ref>{{Cite journal|last=Rourk|first=Christopher John|date=September 2018|title=Ferritin and neuromelanin "quantum dot" array structures in dopamine neurons of the substantia nigra pars compacta and norepinephrine neurons of the locus coeruleus|journal=Biosystems|volume=171|pages=48–58|doi=10.1016/j.biosystems.2018.07.008|pmid=30048795|s2cid=51722018|issn=0303-2647|doi-access=free|bibcode=2018BiSys.171...48R}}</ref> although the hypothesis itself has not yet been directly investigated. The hypothesis and these observations have been applied to [[Integrated Information Theory]].<ref>{{Cite journal|last=Rourk|first=Chris|date=2022-01-06|title=Application of the Catecholaminergic Neuron Electron Transport (CNET) Physical Substrate for Consciousness and Action Selection to Integrated Information Theory|journal=Entropy|volume=24|issue=1|pages=91|doi=10.3390/e24010091|pmid=35052119|pmc=8774445|bibcode=2022Entrp..24...91R|issn=1099-4300|doi-access=free}}</ref>