Cognitive neuropsychology 389579 220969628 2008-06-22T13:20:18Z Lightbot 7178666 Units/dates/other {{neuropsychology}} '''Cognitive neuropsychology''' is a branch of [[neuropsychology]] that aims to understand how the structure and function of the [[brain]] relates to specific [[psychology|psychological]] processes. It places a particular emphasis on studying the [[cognitive]] effects of [[brain injury]] or [[neurological illness]] with a view to inferring models of normal [[cognitive]] functioning. ==History== The modern science of cognitive neuropsychology emerged during the 1960s. However there have been a series of influential studies during the last two centuries which have been critical in laying the foundations for studying brain impairment with a view to understanding normal psychological function. The case of [[Phineas Gage]] was one of the earliest in which a brain injury may have provided clues to the function of a particular brain area. Gage survived an 1848 explosion which drove a 3-foot 7-inch iron rod into his cheek and out the top of his head. Allegedly, the damage to Gage's frontal lobe(s) changed him from a reliable, hard working foreman into a fitful, irresponsible wastrel, suggesting that the frontal lobes may be involved in the psychology of [[emotion]] and [[personality psychology|personality]] (though the extent of Gage's psychological changes seems to have been exaggerated). Similarly, [[Paul Broca]]'s 1861 [[post-mortem examination|post mortem]] study of an [[aphasia|aphasic]] patient, known as 'Tan' after the only word which he could speak, showed that an area of the left [[frontal lobe]] (now known as [[Broca's area]]) was damaged. As Tan was unable to produce speech but could still understand it, Broca argued that this area might be specialised for speech production and that [[language]] skills might be localised to this [[Cerebral cortex|cortical]] area. Clues about the role of the [[occipital lobe]]s in the [[visual system]] were provided by soldiers returning from [[World War I]]. The small bore ammunition often used in this conflict occasionally caused focal brain injuries. Studies of soldiers with such wounds to the back of their head showed that areas of blindness in the [[visual field]] were dependent on which part of the occipital lobe had been damaged, suggesting that specific areas of the brain were responsible for sensation in specific visual areas, known as [[retinotopy]]. Studies on [[HM (patient)|Patient HM]] are commonly cited as some of the precursors, if not the beginning of modern cognitive neuropsychology. HM had parts of his medial temporal lobes surgically removed to treat intractacable [[epilepsy]] in 1953. The treatment proved successful in reducing his dangerous [[seizure]]s, but left him with a profound but selective [[amnesia]]. Because HM's impairment was caused by surgery, the damaged parts of his brain were precisely known, information which was usually not knowable in a time before accurate [[neuroimaging]] became widespread. This allowed detailed connections to be made between theories of memory formation and the brain structures removed in HM. These and similar studies had a number of important implications. The first is that certain [[cognitive]] processes (such as language) could be damaged separately from others, and so might be handled by distinct and independent cognitive and neural processes. The second is that such processes might be localised to specific areas of the brain. Whilst both of these claims are still controversial to some degree, the influence led to a focus on brain injury as a potentially fruitful way of understanding the relationship between [[psychology]] and [[neuroscience]]. During the 1960s, [[information processing]] became the dominant model in [[psychology]] for understanding mental processes. This provided an important theoretical basis for cognitive neuropsychology, as it allowed an explanation of what areas of the brain might be doing (i.e. processing information in specific and specialised ways) and also allowed brain injury to be understood in abstract terms as impairment in the information processing abilities of larger cognitive system. ==Methods== By understanding what a person can no longer do, and correlating this with a knowledge of exactly which parts of the [[nervous system]] are damaged, it is possible to infer previously undiscovered functional relationships. This is called the ''[[lesion]] method''. By using this method, it should also be possible to discover whether a skill is handled by a single cognitive process or a combination of several working together. For example, if a theory states that reading and writing are simply different skills stemming from a single cognitive process, it should not be possible to find a person who, after brain injury, can write but not read or read but not write. This selective breakdown in skills suggests that different parts of the brain are specialised for the different processes and so the cognitive systems are separable. The [[philosopher]] [[Jerry Fodor]] has been particularly influential in cognitive neuropsychology, particularly with the idea that the mind, or at least certain parts of it, may be organised into independent modules. Evidence that cognitive skills may be damaged independently seem to support this theory to some degree, although it is clear that some aspects of mind (such as [[belief]] for example) are unlikely to be modular. Ironically, Fodor (a strict [[Functionalism (philosophy of mind)|functionalist]]) rejects the idea that the neurological properties of the brain have any bearing on its cognitive properties and doubts the whole discipline of cognitive neuropsychology. Cognitive neuropsychology also uses many of the same techniques and technologies from the wider science of [[neuropsychology]] and fields such as [[cognitive neuroscience]]. These may include [[neuroimaging]], [[electrophysiology]] and [[neuropsychological tests]] to measure either brain function or psychological performance. The principles of cognitive neuropsychology have recently been applied to [[mental illness]], with a view to understanding, for example, what the study of [[delusion]]s may tell us about the function of normal belief. This relatively young field is known as [[cognitive neuropsychiatry]]. ==See also== * [[Capgras delusion]] * [[Clive Wearing]] * [[cognitive bias]] * [[cognitive neuropsychiatry]] * [[Cotard delusion]] * [[emotion and memory]] * [[Erotomania]], also known as De Clerambault syndrome * [[face perception]] * [[Fregoli delusion]] * [[HM (patient)]] * [[neuropsychological test]] * [[Phineas Gage]] * [[primary sensory cortex]] * [[prosopagnosia]] * [[retinotopy]] ==Further reading== * {{cite book || last = Shallice | first = Tim | authorlink = Tim Shallice | year = 1988 | title = From Neuropsychology to Mental Structure | id = ISBN 0-521-31360-0 }} {{Psychology}} [[Category:neuropsychology]] [[Category:cognition]] [[lt:KognityvinÄ— neuropsichologija]]