Editing Cognitive neuroscience (section)

==Historical origins==
[[File:Historycognitiveneuroscience.jpg|thumb|alt=Timeline of development of field of cognitive neuroscience|Timeline showing major developments in science that led to the emergence of the field cognitive neuroscience.|400px]]

Cognitive neuroscience is an interdisciplinary area of study that has emerged from [[neuroscience]] and [[psychology]].{{sfn|Kosslyn|Andersen|1995|p={{pn|date=March 2025}}}} There are several stages in these disciplines that have changed the way researchers approached their investigations and that led to the field becoming fully established.

Although the task of cognitive neuroscience is to describe the neural mechanisms associated with the mind, historically it has progressed by investigating how a certain area of the brain supports a given mental faculty. However, early efforts to subdivide the brain proved to be problematic. The phrenologist movement failed to supply a scientific basis for its theories and has since been rejected. The aggregate field view, meaning that all areas of the brain participated in all behavior,<ref name="Erickson-Davis">{{cite thesis |last1=Erickson-Davis |first1=Cordelia |title=Neurofeedback Training for Parkinsonian Tremor and Bradykinesia |date=16 February 2011 |hdl=10166/626 }}{{pn|date=March 2025}}</ref> was also rejected as a result of brain mapping, which began with [[Hitzig]] and [[Gustav Fritsch|Fritsch]]'s experiments<ref name="Fritsch & Hitzig 2009">{{cite journal |last1=Fritsch |first1=G. |last2=Hitzig |first2=E. |title=Electric excitability of the cerebrum (Über die elektrische Erregbarkeit des Grosshirns) |journal=Epilepsy & Behavior |date=June 2009 |volume=15 |issue=2 |pages=123–130 |doi=10.1016/j.yebeh.2009.03.001 |pmid=19457461 }}</ref> and eventually developed through methods such as [[positron emission tomography]] (PET) and [[functional magnetic resonance imaging]] (fMRI).<ref name="Raichle 2009">{{cite journal | last1 = Raichle | first1 = Marcus E. | year = 2009 | title = A brief history of human brain mapping | journal = Trends in Neurosciences | volume = 32 | issue = 2| pages = 118–126 | doi=10.1016/j.tins.2008.11.001| pmid = 19110322 }}</ref> [[Gestalt psychology|Gestalt theory]], [[neuropsychology]], and the [[cognitive revolution]] were major turning points in the creation of cognitive neuroscience as a field, bringing together ideas and techniques that enabled researchers to make more links between behavior and its neural substrates.

While the Ancient Greeks [[Alcmaeon of Croton|Alcmaeon]], [[Plato]], [[Aristotle]] in the 5th and 4th centuries BC,<ref>Guthri WKC (1971). ''A History of Greek Philosophy''. London: Cambridge University Press. p. 348.</ref> and then the Roman physician [[Galen]] in the 2nd century AD<ref>{{cite journal |last1=Lloyd |first1=Geoffrey |title=Pneuma between body and soul |journal=Journal of the Royal Anthropological Institute |date=April 2007 |volume=13 |issue=s1 |doi=10.1111/j.1467-9655.2007.00409.x }}</ref> already argued that the brain is the source of mental activity, scientific research into the connections between brain areas and cognitive functions began in the second half of the 19th century. The founding insights in the Cognitive neuroscience establishment were:

* In 1861, French neurologist [[Paul Broca]] discovered that a damaged area of the posterior inferior frontal gyrus (pars triangularis, BA45, also known as [[Broca's area]]) in patients caused an inability to speak.<ref>{{cite journal |last1=Dronkers |first1=N. F. |last2=Plaisant |first2=O. |last3=Iba-Zizen |first3=M. T. |last4=Cabanis |first4=E. A. |title=Paul Broca's historic cases: high resolution MR imaging of the brains of Leborgne and Lelong |journal=Brain |date=2 April 2007 |volume=130 |issue=5 |pages=1432–1441 |doi=10.1093/brain/awm042 |pmid=17405763 }}</ref> His work "Localization of Speech in the Third Left Frontal Cultivation" in 1865 inspired others to study brain regions linking them to sensory and motor functions.<ref>{{cite book |last1=Schiller |first1=F |date=1979 |title=Paul Broca, Founder of French Anthropology, Explorer of the Brain |publisher=University of California Press |isbn=978-0-520-03744-1 |pages=192–197 }}</ref>

* In 1870, German physicians [[Eduard Hitzig]] and [[Gustav Fritsch]] stimulated the cerebral cortex of a dog with electricity, causing different muscles to contract depending on the areas of the brain involved. This led to the suggestion that individual functions are localized to specific areas of the brain.<ref name="Fritsch & Hitzig 2009" />

* Italian neuroanatomist professor [[Camillo Golgi]] discovered in the 1870s that nerve cells could be colored using silver nitrate allowing Golgi to argue that all the nerve cells in the nervous system are a continuous, interconnected network.<ref>"Camillo Golgi – Facts". ''NobelPrize.org''. Nobel Prize Outreach AB 2025. Tue. 14 Jan 2025. https://www.nobelprize.org/prizes/medicine/1906/golgi/facts/ </ref>

* In 1874,  German neurologist and psychiatrist [[Carl Wernicke]] hypothesized an association between the left posterior section of the superior temporal gyrus and the reflexive mimicking of words and their syllables.<ref>{{cite book |last1=Wernicke |first1=K |date=1995 |chapter=The aphasia symptom-complex: A psychological study on an anatomical basis (1875) |editor1-first=Paul |editor1-last=Eling |title=Reader in the History of Aphasia: From Franz Gall to Norman Geschwind |volume=4 |location=Amsterdam |publisher=John Benjamins Pub Co |pages=69–89 |isbn=978-90-272-1893-3 }}</ref>

* In 1878, Italian professor of pharmacology and physiology [[Angelo Mosso]] associated blood flow with brain functions. He invented the first neuroimaging technique, known as 'human circulation balance'. Angelo Mosso is a forerunner of more refined techniques like functional magnetic resonance imaging (fMRI) and positron emission tomography (PET).<ref>{{cite journal |last1=Sandrone |first1=Stefano |last2=Bacigaluppi |first2=Marco |last3=Galloni |first3=Marco R. |last4=Cappa |first4=Stefano F. |last5=Moro |first5=Andrea |last6=Catani |first6=Marco |last7=Filippi |first7=Massimo |last8=Monti |first8=Martin M. |last9=Perani |first9=Daniela |last10=Martino |first10=Gianvito |title=Weighing brain activity with the balance: Angelo Mosso's original manuscripts come to light |journal=Brain |date=February 2014 |volume=137 |issue=2 |pages=621–633 |doi=10.1093/brain/awt091 |pmid=23687118 |hdl=2318/141932 |hdl-access=free }}</ref>

* In 1887, Spanish neuroanatomist professor [[Santiago Ramón y Cajal]] (1852–1934) improved the Golgi's method of visualizing nervous tissue under light microscopy by using a technique he termed "double impregnation". He discovered a number of facts about the organization of the nervous system: the nerve cell as an independent cell, insights into degeneration and regeneration, and ideas on [[Neuroplasticity|brain plasticity]].<ref>{{cite journal |last1=Rozo |first1=Jairo A. |last2=Martínez-Gallego |first2=Irene |last3=Rodríguez-Moreno |first3=Antonio |title=Cajal, the neuronal theory and the idea of brain plasticity |journal=Frontiers in Neuroanatomy |date=19 February 2024 |volume=18 |doi=10.3389/fnana.2024.1331666 |doi-access=free |pmid=38440067 |pmc=10910026 }}</ref>

* In 1894, neurologist and psychiatrist [[Edward Flatau]] published a human brain atlas “Atlas of the Human Brain and the Course of the Nerve-Fibres” which consisted of long-exposure photographs of fresh brain sections. It contained an overview of the knowledge of the time on the fibre pathways in the central nervous system.<ref>{{cite journal |last1=Freud |first1=S |date=1894 |title=Kritische Besprechungen und literarische Anzeigen: Atlas des menschlichen Gehirns und des Faserverlaufes von Ed. Flatau |journal=Int Klin Rundsch |volume=8 |pages=1131–1132 }}</ref>

* In 1909, German anatomist [[Korbinian Brodmann]] published his original research on brain mapping in the monograph Vergleichende Lokalisationslehre der Großhirnrinde (Localisation in the cerebral cortex), defining 52 distinct regions of the cerebral cortex, known as [[Brodmann area|Brodmann areas]] now, based on regional variations in structure. These Brodmann areas were associated with diverse functions including sensation, motor control, and cognition.<ref>{{cite journal |last1=Guillery |first1=R. W. |title=Brodmann's ' Localisation in the Cerebral Cortex '. Translated and edited by L AURENCE J. G AREY . (Pp. xviii+300; illustrated; £28 hardback; ISBN 1 86094 176 1.) London: Imperial College Press. 1999. |journal=Journal of Anatomy |date=April 2000 |volume=196 |issue=3 |pages=493–496 |doi=10.1046/j.1469-7580.2000.196304931.x |pmc=1468084 }}</ref>
* In 1924, German physiologist and psychiatrist [[Hans Berger]] (1873–1941) recorded the first human [[Electroencephalography|electroencephalogram EEG]], discovering the electrical activity of the brain (called [[Neural oscillation|brain waves]]) and, in particular, the [[Alpha wave|alpha wave rhythm]], which is a type of brain wave.<ref>{{cite journal |last1=Haas |first1=L F |title=Hans Berger (1873-1941), Richard Caton (1842-1926), and electroencephalography |journal=Journal of Neurology, Neurosurgery & Psychiatry |date=2003 |volume=74 |issue=1 |pages=9 |doi=10.1136/jnnp.74.1.9 |pmid=12486257 |pmc=1738204 }}</ref><ref>{{cite journal |last1=İnce |first1=Rümeysa |last2=Adanır |first2=Saliha Seda |last3=Sevmez |first3=Fatma |title=The inventor of electroencephalography (EEG): Hans Berger (1873–1941) |journal=Child's Nervous System |date=September 2021 |volume=37 |issue=9 |pages=2723–2724 |doi=10.1007/s00381-020-04564-z |pmid=32140776 }}</ref>
* A first clinical positron imaging device, a prototype of a modern [[Positron emission tomography|Positron Emission Tomography]] (PET), was invented in 1953 by Dr. Brownell and Dr. Aronow.<ref>{{cite journal |last1=Brownell |first1=GL |last2=Sweet |first2=WH |date=1953 |title=Localization of brain tumors with positron emitters |journal=Nucleonics |volume=11 |issue=11 |pages=40–45 }}</ref> American scientists specializing in nuclear medicine David Edmund Kuhl, Luke Chapman and Roy Edwards developed this new method of tomographic imaging and constructed several tomographic instruments in the late 1950s. Ph.D. in Chemistry Michael E. Phelps was able to invent their insights into the first PET scanner in 1973.<ref>Michael E. Phelps, the Enrico Fermi Award 1998. US Department of energy. Retrieved 18.01.2025 from https://science.osti.gov/fermi/Award-Laureates/1990s/phelps </ref> PET became a valuable research tool to study brain functioning. This technique can indirectly measure radioactivity signal that indicates increased blood flow associated with increased brain activity.<ref>{{cite book |last1=Cherry |first1=Simon R. |last2=Sorenson |first2=James A. |last3=Phelps |first3=Michael E. |title=Physics in Nuclear Medicine |date=2012 |publisher=Elsevier Health Sciences |location=60 |isbn=978-1-4557-3367-5 }}</ref>
* In 1971, American chemist and physicist [[Paul Lauterbur|Paul Christian Lauterbur]] invented the idea of MR imaging ([[Magnetic resonance imaging|MRI]]). In 2003, he received the Nobel Prize. MRI is the investigative tool for contrasting grey and white matter, which makes MRI the choice to study many conditions of the central nervous system.<ref>{{cite journal |last1=Filler |first1=Aaron |title=The History, Development and Impact of Computed Imaging in Neurological Diagnosis and Neurosurgery: CT, MRI, and DTI |journal=Nature Precedings |date=July 2009 |doi=10.1038/npre.2009.3267.4 |doi-access=free }}</ref> This method contributed to the development of [[Functional magnetic resonance imaging|Functional Magnetic Resonance Imaging]] (fMRI), which has been used in many studies in cognitive neuroscience since 1990s.<ref>{{cite journal |last1=Glover |first1=Gary H. |title=Overview of Functional Magnetic Resonance Imaging |journal=Neurosurgery Clinics of North America |date=April 2011 |volume=22 |issue=2 |pages=133–139 |doi=10.1016/j.nec.2010.11.001 |pmid=21435566 |pmc=3073717 }}</ref>

===Origins in philosophy===
Philosophers have always been interested in the mind: "the idea that explaining a phenomenon involves understanding the mechanism responsible for it has deep roots in the History of Philosophy from atomic theories in 5th century B.C. to its rebirth in the 17th and 18th century in the works of Galileo, Descartes, and Boyle. Among others, it's Descartes' idea that machines humans build could work as models of scientific explanation."<ref>{{cite journal|last1=Sirgiovanni|first1=Elisabetta|title=The Mechanistic Approach to Psychiatric Classification|journal=Dialogues in Philosophy, Mental and Neuro Sciences|date=2009|volume=2|issue=2|pages=45–49|url=http://www.crossingdialogues.com/Ms-C09-02.pdf}}</ref>
For example, [[Aristotle]] thought the brain was the body's cooling system and the [[cardiocentric hypothesis|capacity for intelligence was located in the heart]]. It has been suggested that the first person to believe otherwise was the Roman physician [[Galen]] in the second century AD, who declared that the brain was the source of mental activity,<ref name=Uttal2011>{{cite book |last1=Uttal |first1=William R. |title=Mind and Brain: A Critical Appraisal of Cognitive Neuroscience |date=2011 |publisher=MIT Press |isbn=978-0-262-29803-2 }}{{page needed|date=December 2021}}</ref> although this has also been accredited to [[Alcmaeon of Croton|Alcmaeon]].<ref>{{cite journal |last1=Gross |first1=Charles G. |title=Aristotle on the Brain |journal=The Neuroscientist |date=July 1995 |volume=1 |issue=4 |pages=245–250 |doi=10.1177/107385849500100408 }}</ref> However, Galen believed that personality and emotion were not generated by the brain, but rather by other organs. [[Andreas Vesalius]], an anatomist and physician, was the first to believe that the brain and the nervous system are the center of the mind and emotion.<ref>{{cite journal |last1=Smith |first1=C.U.M. |title=Cardiocentric Neurophysiology: The Persistence of a Delusion |journal=Journal of the History of the Neurosciences |date=January 2013 |volume=22 |issue=1 |pages=6–13 |doi=10.1080/0964704X.2011.650899 |pmid=23323528 }}</ref> [[Psychology]], a major contributing field to cognitive neuroscience, emerged from philosophical reasoning about the mind.<ref>{{cite journal |last1=Hatfield |first1=Gary |title=Psychology, Philosophy, and Cognitive Science: Reflections on the History and Philosophy of Experimental Psychology |journal=Mind & Language |date=June 2002 |volume=17 |issue=3 |pages=207–232 |doi=10.1111/1468-0017.00196 }}</ref>

===19th century===

====Phrenology====
[[File:Phrenology journal (1848).jpg|thumb|right|upright|A page from the ''American Phrenological Journal'']]
{{Main|Phrenology}}
One of the predecessors to cognitive neuroscience was [[phrenology]], a [[pseudoscience|pseudoscientific]] approach that claimed that behavior could be determined by the shape of the [[scalp]]. In the early 19th century, [[Franz Joseph Gall]] and [[J. G. Spurzheim]] believed that the human brain was localized into approximately 35 different sections. In his book, The Anatomy and Physiology of the Nervous System in General, and of the Brain in Particular, Gall claimed that a larger bump in one of these areas meant that that area of the brain was used more frequently by that person. This theory gained significant public attention, leading to the publication of phrenology journals and the creation of phrenometers, which measured the bumps on a human subject's head. While phrenology remained a fixture at fairs and carnivals, it did not enjoy wide acceptance within the scientific community.{{sfn|Bear|Connors|Paradiso|2007|pp=10–11}} The major criticism of phrenology is that researchers were not able to test theories empirically.{{sfn|Kosslyn|Andersen|1995|p={{pn|date=March 2025}}}}

====Localizationist view====
The localizationist view was concerned with mental abilities being localized to specific areas of the brain rather than on what the characteristics of the abilities were and how to measure them.{{sfn|Kosslyn|Andersen|1995|p={{pn|date=March 2025}}}} Studies performed in Europe, such as those of [[John Hughlings Jackson]], supported this view. Jackson studied patients with [[brain damage]], particularly those with [[epilepsy]]. He discovered that the epileptic patients often made the same [[clonus|clonic]] and tonic movements of muscle during their seizures, leading Jackson to believe that they must be caused by activity in the same place in the brain every time. Jackson proposed that specific functions were localized to specific areas of the brain,<ref>Enersen, O. D. 2009</ref> which was critical to future understanding of the [[brain lobes]].

====Aggregate field view====
According to the aggregate field view, all areas of the brain participate in every mental function.<ref name="Erickson-Davis"/>

[[Pierre Flourens]], a French experimental psychologist, challenged the localizationist view by using animal experiments.{{sfn|Kosslyn|Andersen|1995|p={{pn|date=March 2025}}}} He discovered that removing the [[cerebellum]] (brain) in rabbits and pigeons affected their sense of muscular coordination, and that all cognitive functions were disrupted in pigeons when the [[cerebral hemisphere]]s were removed. From this he concluded that the [[cerebral cortex]], [[cerebellum]], and [[brainstem]] functioned together as a whole.<ref name = "Boring, E.G. (1957). A history of experimental psychology. New York. ">Boring, E.G. (1957). A history of experimental psychology. New York.{{pn|date=March 2025}}</ref> His approach has been criticised on the basis that the tests were not sensitive enough to notice selective deficits had they been present.{{sfn|Kosslyn|Andersen|1995|p={{pn|date=March 2025}}}}

====Emergence of neuropsychology====
Perhaps the first serious attempts to localize mental functions to specific locations in the brain was by [[Paul Broca|Broca]] and [[Carl Wernicke|Wernicke]]. This was mostly achieved by studying the effects of injuries to different parts of the brain on psychological functions.<ref name=Uttal2011/> In 1861, French neurologist Paul Broca came across a man with a disability who was able to understand the language but unable to speak. The man could only produce the sound "tan". It was later discovered that the man had damage to an area of his left frontal lobe now known as [[Broca's area]]. Carl Wernicke, a [[Germany|German]] [[neurologist]], found a patient who could speak fluently but non-sensibly. The patient had been the victim of a [[stroke]], and could not understand spoken or written language. This patient had a lesion in the area where the left parietal and temporal lobes meet, now known as [[Wernicke's area]]. These cases, which suggested that lesions caused specific behavioral changes, strongly supported the localizationist view. Additionally, Aphasia is a learning disorder which was also discovered by Paul Broca. According to, Johns Hopkins School of Medicine, Aphasia is a language disorder caused by damage in a specific area of the brain that controls language expression and comprehension.<ref>{{Cite web |title=Aphasia |url=https://www.hopkinsmedicine.org/health/conditions-and-diseases/aphasia |access-date=2022-04-27 |website=www.hopkinsmedicine.org |language=en}}</ref> This can often lead to the person speaking words with no sense known as "word salad" <ref>{{Cite web |title=Wernicke area {{!}} Definition, Location, Function, & Facts {{!}} Britannica |url=https://www.britannica.com/science/Wernicke-area |access-date=2022-04-27 |website=www.britannica.com |language=en}}</ref>

====Mapping the brain====
In 1870, German physicians [[Eduard Hitzig]] and [[Gustav Fritsch]] published their findings of the behavior of animals. Hitzig and Fritsch ran an electric current through the cerebral cortex of a dog, causing different muscles to contract depending on which areas of the brain were electrically stimulated. This led to the proposition that individual functions are localized to specific areas of the brain rather than the cerebrum as a whole, as the aggregate field view suggests.<ref name="Fritsch & Hitzig 2009"/> [[Korbinian Brodmann|Brodmann]] was also an important figure in brain mapping; his experiments based on Franz Nissl's tissue staining techniques divided the brain into fifty-two areas.

===20th century===

====Cognitive revolution====
{{Main|Cognitive revolution}}
At the start of the 20th century, attitudes in America were characterized by pragmatism, which led to a preference for [[behaviorism]] as the primary approach in [[psychology]]. [[John B. Watson|J.B. Watson]] was a key figure with his stimulus-response approach. By conducting experiments on animals he was aiming to be able to predict and control behavior. Behaviorism eventually failed because it could not provide realistic psychology of human action and thought – it focused primarily on stimulus-response associations at the expense of explaining phenomena like thought and imagination. This led to what is often termed as the "cognitive revolution".<ref>{{cite journal |last1=Mandler |first1=George |title=Origins of the cognitive (r)evolution |journal=Journal of the History of the Behavioral Sciences |date=2002 |volume=38 |issue=4 |pages=339–353 |doi=10.1002/jhbs.10066 |pmid=12404267 |url=https://www.escholarship.org/uc/item/22s8x969 }}</ref>

====Neuron doctrine====
{{Main|Neuron doctrine}}
In the early 20th century, Santiago Ramón y Cajal and Camillo Golgi began working on the structure of the neuron. Golgi developed a [[Golgi's method|silver staining method]] that could entirely stain several cells in a particular area, leading him to believe that neurons were directly connected with each other in one cytoplasm. Cajal challenged this view after staining areas of the brain that had less myelin and discovering that neurons were discrete cells. Cajal also discovered that cells transmit electrical signals down the neuron in one direction only. Both Golgi and Cajal were awarded a Nobel Prize in Physiology or Medicine in 1906 for this work on the neuron doctrine.<ref>{{cite web|url= https://www.nobelprize.org/nobel_prizes/medicine/laureates/1906/|title= The Nobel Prize in Physiology or Medicine 1906}}</ref>

===Mid-late 20th century ===
Several findings in the 20th century continued to advance the field, such as the discovery of [[ocular dominance columns]], recording of single nerve cells in animals, and coordination of eye and head movements. Experimental psychology was also significant in the foundation of cognitive neuroscience. Some particularly important results were the demonstration that some tasks are accomplished via discrete processing stages, the study of attention,<ref>{{cite journal |last1=Carrasco |first1=Marisa |title=Visual attention: The past 25 years |journal=Vision Research |date=2011 |volume=51 |issue=13 |pages=1484–1525 |doi=10.1016/j.visres.2011.04.012|pmid=21549742 |pmc=3390154 }}</ref><ref>{{cite journal |last1=Kastner |first1=Sabine |last2=Ungerleider |first2=Leslie G. |title=Mechanisms of visual attention in the human cortex |journal=Annual Review of Neuroscience |date=2000 |volume=23 |pages=315–41|pmid=10845067 |doi=10.1146/annurev.neuro.23.1.315 }}</ref> and the notion that behavioural data do not provide enough information by themselves to explain mental processes. As a result, some experimental psychologists began to investigate neural bases of behaviour. 
Wilder Penfield created maps of primary sensory and motor areas of the brain by stimulating the cortices of patients during surgery. The work of [[Roger Wolcott Sperry|Sperry]] and [[Michael Gazzaniga|Gazzaniga]] on split brain patients in the 1950s was also instrumental in the progress of the field.<ref name=Uttal2011/> The term cognitive neuroscience itself was coined by Gazzaniga and cognitive psychologist [[George Armitage Miller]] while sharing a taxi in 1976.<ref>{{cite book |last=Gazzaniga|first=Michael |author-link=Michael S. Gazzaniga|date=1984|title=Handbook of Cognitive Neuroscience|pages=vii|chapter=Preface}}</ref>

====Brain mapping ====
New brain mapping technology, particularly [[functional magnetic resonance imaging|fMRI]] and [[positron emission tomography|PET]], allowed researchers to investigate experimental strategies of [[cognitive psychology]] by observing brain function. Although this is often thought of as a new method (most of the technology is relatively recent), the underlying principle goes back as far as 1878 when blood flow was first associated with brain function.<ref name="Raichle 2009" /> [[Angelo Mosso]], an Italian psychologist of the 19th century, had monitored the pulsations of the adult brain through neurosurgically created bony defects in the skulls of patients. He noted that when the subjects engaged in tasks such as mathematical calculations the pulsations of the brain increased locally. Such observations led Mosso to conclude that blood flow of the brain followed function.<ref name="Raichle 2009" />

Commonly the cerebrum is divided into 5 sections: the frontal lobe, occipital lobe, temporal lobes, parietal lobe, and the insula.<ref name=":2">{{cite journal |last1=Casillo |first1=Stephanie M. |last2=Luy |first2=Diego D. |last3=Goldschmidt |first3=Ezequiel |title=A History of the Lobes of the Brain |journal=World Neurosurgery |date=February 2020 |volume=134 |pages=353–360 |doi=10.1016/j.wneu.2019.10.155 |pmid=31682988 }}</ref> The brain is also divided into fissures and sulci.<ref name=":3">{{Cite journal |last=Ribas |first=Guilherme Carvalhal |date=February 2010 |title=The cerebral sulci and gyri |journal=Neurosurgical Focus |volume=28 |issue=2 |pages=E2 |doi=10.3171/2009.11.FOCUS09245 |pmid=20121437 }}</ref> The lateral sulcus called the Sylvian Fissure separates the frontal and temporal lobes. The insula is described as being deep to this lateral fissure. The longitudinal fissure separates the lobes of the brain length-wise. Lobes are considered to be distinct in their distribution of vessels.<ref name=":2" /> The overall surface consists of sulci and gyri which are necessary to identify for neuroimaging purposes.<ref name=":3" />