Cognition refers to "the mental action or process of acquiring knowledge and understanding through thought, experience, and the senses". It encompasses all aspects of intellectual functions and processes such as: perception,

attention Attention is the behavioral and cognitive process of selectively concentrating on a discrete aspect of information, whether considered subjective or objective, while ignoring other perceivable information. William James (1890) wrote that "Atte ...

thought In their most common sense, the terms thought and thinking refer to conscious cognitive processes that can happen independently of sensory stimulation. Their most paradigmatic forms are judging, reasoning, concept formation, problem solving, a ...

, intelligence, the formation of knowledge, memory and working memory, judgment and evaluation,

reasoning Reason is the capacity of consciously applying logic by drawing conclusions from new or existing information, with the aim of seeking the truth. It is closely associated with such characteristically human activities as philosophy, science, lang ...

and

computation Computation is any type of arithmetic or non-arithmetic calculation that follows a well-defined model (e.g., an algorithm). Mechanical or electronic devices (or, historically, people) that perform computations are known as ''computers''. An es ...

problem solving Problem solving is the process of achieving a goal by overcoming obstacles, a frequent part of most activities. Problems in need of solutions range from simple personal tasks (e.g. how to turn on an appliance) to complex issues in business an ...

and

decision making In psychology, decision-making (also spelled decision making and decisionmaking) is regarded as the cognitive process resulting in the selection of a belief or a course of action among several possible alternative options. It could be either rati ...

comprehension Comprehension may refer to: * Comprehension (logic), the totality of intensions, that is, properties or qualities, that an object possesses * Comprehension approach, several methodologies of language learning that emphasize understanding languag ...

and production of language.

Imagination Imagination is the production or simulation of novel objects, sensations, and ideas in the mind without any immediate input of the senses. Stefan Szczelkun characterises it as the forming of experiences in one's mind, which can be re-creations ...

is also a cognitive process, it is considered as such because it involves thinking about possibilities. Cognitive processes use existing knowledge and discover new knowledge. Cognitive processes are analyzed from different perspectives within different contexts, notably in the fields of linguistics,

musicology Musicology (from Greek μουσική ''mousikē'' 'music' and -λογια ''-logia'', 'domain of study') is the scholarly analysis and research-based study of music. Musicology departments traditionally belong to the humanities, although some mu ...

anesthesia Anesthesia is a state of controlled, temporary loss of sensation or awareness that is induced for medical or veterinary purposes. It may include some or all of analgesia (relief from or prevention of pain), paralysis (muscle relaxation), ...

, neuroscience, psychiatry, psychology, education,

philosophy Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. Some ...

, anthropology, biology,

systemics In the context of systems science and systems philosophy, systemics is an initiative to study systems. It is an attempt at developing logical, mathematical, engineering and philosophical paradigms and frameworks in which physical, technological, ...

, logic, and computer science. These and other approaches to the analysis of cognition (such as

embodied cognition Embodied cognition is the theory that many features of cognition, whether human or otherwise, are shaped by aspects of an organism's entire body. Sensory and motor systems are seen as fundamentally integrated with cognitive processing. The cognit ...

) are synthesized in the developing field of cognitive science, a progressively autonomous academic discipline.

Etymology

The word ''cognition'' dates back to the 15th century, where it meant " thinking and awareness". The term comes from the Latin noun ('examination,' 'learning,' or 'knowledge'), derived from the verb , a compound of ('with') and ('know'). The latter half, ''gnōscō'', itself is a

cognate In historical linguistics, cognates or lexical cognates are sets of words in different languages that have been inherited in direct descent from an etymology, etymological ancestor in a proto-language, common parent language. Because language c ...

of a Greek verb, ' ().

Early studies

Despite the word ''cognitive'' itself dating back to the 15th century, attention to ''cognitive processes'' came about more than eighteen centuries earlier, beginning with Aristotle (384–322 BC) and his interest in the inner workings of the mind and how they affect the human experience. Aristotle focused on cognitive areas pertaining to memory, perception, and mental imagery. He placed great importance on ensuring that his studies were based on empirical evidence, that is, scientific information that is gathered through observation and conscientious experimentation. Two millennia later, the groundwork for modern concepts of cognition was laid during the

Enlightenment Enlightenment or enlighten may refer to: Age of Enlightenment * Age of Enlightenment, period in Western intellectual history from the late 17th to late 18th century, centered in France but also encompassing (alphabetically by country or culture): ...

by thinkers such as

John Locke John Locke (; 29 August 1632 – 28 October 1704) was an English philosopher and physician, widely regarded as one of the most influential of Age of Enlightenment, Enlightenment thinkers and commonly known as the "father of liberalism ...

and Dugald Stewart who sought to develop a model of the mind in which ideas were acquired, remembered and manipulated. During the early nineteenth century cognitive models were developed both in

—particularly by authors writing about the philosophy of mind—and within medicine, especially by physicians seeking to understand how to cure madness. In Britain, these models were studied in the academy by scholars such as

James Sully James Sully (3 March 1842 – 1 November 1923) was an English psychologist. Biography James Sully was born at Bridgwater, Somerset, the son of J. W. Sully, a liberal Baptist merchant and ship-owner. He was educated at the Independent Colle ...

at University College London, and they were even used by politicians when considering the national ''Elementary Education Act'' of 1870. As psychology emerged as a burgeoning field of study in Europe, whilst also gaining a following in

America The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, scientists such as

Wilhelm Wundt Wilhelm Maximilian Wundt (; ; 16 August 1832 – 31 August 1920) was a German physiologist, philosopher, and professor, known today as one of the fathers of modern psychology. Wundt, who distinguished psychology as a science from philosophy and ...

Herman Ebbinghaus Hermann Ebbinghaus (24 January 185026 February 1909) was a German psychologist who pioneered the experimental study of memory, and is known for his discovery of the forgetting curve and the spacing effect. He was also the first person to describ ...

, Mary Whiton Calkins, and William James would offer their contributions to the study of human cognition.

Early theorists

(1832–1920) emphasized the notion of what he called '' introspection'': examining the inner feelings of an individual. With introspection, the subject had to be careful to describe their feelings in the most objective manner possible in order for Wundt to find the information scientific. Though Wundt's contributions are by no means minimal, modern psychologists find his methods to be too subjective and choose to rely on more objective procedures of experimentation to make conclusions about the human cognitive process.

Hermann Ebbinghaus Hermann Ebbinghaus (24 January 185026 February 1909) was a German psychologist who pioneered the experimental study of memory, and is known for his discovery of the forgetting curve and the spacing effect. He was also the first person to describ ...

(1850–1909) conducted cognitive studies that mainly examined the function and capacity of human memory. Ebbinghaus developed his own experiment in which he constructed over 2,000 syllables made out of nonexistent words (for instance, 'EAS'). He then examined his own personal ability to learn these non-words. He purposely chose non-words as opposed to real words to control for the influence of pre-existing experience on what the words might symbolize, thus enabling easier recollection of them. Ebbinghaus observed and hypothesized a number of variables that may have affected his ability to learn and recall the non-words he created. One of the reasons, he concluded, was the amount of time between the presentation of the list of stimuli and the recitation or recall of the same. Ebbinghaus was the first to record and plot a "

learning curve A learning curve is a graphical representation of the relationship between how Skill, proficient people are at a task and the amount of experience they have. Proficiency (measured on the vertical axis) usually increases with increased experience ...

" and a "

forgetting curve The forgetting curve hypothesizes the decline of memory retention in time. This curve shows how information is lost over time when there is no attempt to retain it. A related concept is the strength of memory that refers to the durability that m ...

". His work heavily influenced the study of serial position and its effect on memory (discussed further below). Mary Whiton Calkins (1863–1930) was an influential American pioneer in the realm of psychology. Her work also focused on human memory capacity. A common theory, called the

recency effect Serial-position effect is the tendency of a person to recall the first and last items in a series best, and the middle items worst. The term was coined by Hermann Ebbinghaus through studies he performed on himself, and refers to the finding that r ...

, can be attributed to the studies that she conducted. The recency effect, also discussed in the subsequent experiment section, is the tendency for individuals to be able to accurately recollect the final items presented in a sequence of stimuli. Calkin's theory is closely related to the aforementioned study and conclusion of the memory experiments conducted by Hermann Ebbinghaus. William James (1842–1910) is another pivotal figure in the history of cognitive science. James was quite discontent with Wundt's emphasis on introspection and Ebbinghaus' use of nonsense stimuli. He instead chose to focus on the human learning experience in everyday life and its importance to the study of cognition. James' most significant contribution to the study and theory of cognition was his textbook ''Principles of Psychology'' which preliminarily examines aspects of cognition such as perception, memory, reasoning, and attention. René Descartes (1596-1650) was a seventeenth-century philosopher who came up with the phrase "Cogito, ergo sum." Which means "I think, therefore I am." He took a philosophical approach to the study of cognition and the mind, with his Meditations he wanted people to meditate along with him to come to the same conclusions as he did but in their own free cognition.

Psychology

In psychology, the term "cognition" is usually used within an

information processing Information processing is the change (processing) of information in any manner detectable by an observer. As such, it is a process that ''describes'' everything that happens (changes) in the universe, from the falling of a rock (a change in posit ...

view of an individual's psychological functions, and such is the same in cognitive engineering. In the study of social cognition, a branch of social psychology, the term is used to explain attitudes, attribution, and group dynamics. However, psychological research within the field of cognitive science has also suggested an embodied approach to understanding cognition. Contrary to the traditional computationalist approach,

emphasizes the body's significant role in the acquisition and development of cognitive capabilities. Human cognition is conscious and unconscious, concrete or abstract, as well as

intuitive Intuition is the ability to acquire knowledge without recourse to conscious reasoning. Different fields use the word "intuition" in very different ways, including but not limited to: direct access to unconscious knowledge; unconscious cognition; ...

(like knowledge of a language) and

conceptual Conceptual may refer to: Philosophy and Humanities *Concept *Conceptualism *Philosophical analysis (Conceptual analysis) *Theoretical definition (Conceptual definition) *Thinking about Consciousness (Conceptual dualism) *Pragmatism (Conceptual pr ...

(like a model of a language). It encompasses processes such as memory, association,

concept formation Concept learning, also known as category learning, concept attainment, and concept formation, is defined by Bruner, Goodnow, & Austin (1967) as "the search for and listing of attributes that can be used to distinguish exemplars from non exemplars ...

, pattern recognition, language,

, perception, action,

, and mental imagery. Traditionally, emotion was not thought of as a cognitive process, but now much research is being undertaken to examine the

cognitive psychology Cognitive psychology is the scientific study of mental processes such as attention, language use, memory, perception, problem solving, creativity, and reasoning. Cognitive psychology originated in the 1960s in a break from behaviorism, which ...

of emotion; research is also focused on one's awareness of one's own strategies and methods of cognition, which is called

metacognition Metacognition is an awareness of one's thought processes and an understanding of the patterns behind them. The term comes from the root word '' meta'', meaning "beyond", or "on top of".Metcalfe, J., & Shimamura, A. P. (1994). ''Metacognition: knowi ...

. The concept of cognition has gone through several revisions through the development of disciplines within psychology. Psychologists initially understood cognition governing human action as information processing. This was a movement known as cognitivism in the 1950s, emerging after the Behaviorist movement viewed cognition as a form of behavior. Cognitivism approached cognition as a form of computation, viewing the mind as a machine and consciousness as an executive function. However; post cognitivism began to emerge in the 1990s as the development of cognitive science presented theories that highlighted the necessity of cognitive action as embodied, extended, and producing dynamic processes in the mind. The development of Cognitive psychology arose as psychology from different theories, and so began exploring these dynamics concerning mind and environment, starting a movement from these prior dualist paradigms that prioritized cognition as systematic computation or exclusively behavior.

Piaget's theory of cognitive development

For years,

sociologists This is a list of sociologists. It is intended to cover those who have made substantive contributions to social theory and research, including any sociological subfield. Scientists in other fields and philosophers are not included, unless at least ...

and

psychologist A psychologist is a professional who practices psychology and studies mental states, perceptual, cognitive, emotional, and social processes and behavior. Their work often involves the experimentation, observation, and interpretation of how indi ...

s have conducted studies on cognitive development, i.e. the construction of human thought or mental processes. Jean Piaget was one of the most important and influential people in the field of

developmental psychology Developmental psychology is the science, scientific study of how and why humans grow, change, and adapt across the course of their lives. Originally concerned with infants and children, the field has expanded to include adolescence, adult deve ...

. He believed that humans are unique in comparison to animals because we have the capacity to do "abstract symbolic reasoning". His work can be compared to Lev Vygotsky, Sigmund Freud, and

Erik Erikson Erik Homburger Erikson (born Erik Salomonsen; 15 June 1902 – 12 May 1994) was a German-American developmental psychologist and psychoanalyst known for his theory on psychological development of human beings. He coined the phrase identity cr ...

who were also great contributors in the field of developmental psychology. Today, Piaget is known for studying the cognitive development in children, having studied his own three children and their intellectual development, from which he would come to a theory of cognitive development that describes the developmental stages of childhood.

Common types of tests on human cognition

Serial position The '' serial position experiment'' is meant to test a theory of memory that states that when information is given in a serial manner, we tend to remember information at the beginning of the sequence, called the ''primacy effect'', and information at the end of the sequence, called the ''recency effect''. Consequently, information given in the middle of the sequence is typically forgotten, or not recalled as easily. This study predicts that the recency effect is stronger than the primacy effect, because the information that is most recently learned is still in working memory when asked to be recalled. Information that is learned first still has to go through a retrieval process. This experiment focuses on human memory processes. Word superiority The '' word superiority experiment'' presents a subject with a word, or a letter by itself, for a brief period of time, i.e. 40ms, and they are then asked to recall the letter that was in a particular location in the word. In theory, the subject should be better able to correctly recall the letter when it was presented in a word than when it was presented in isolation. This experiment focuses on human speech and language. Brown-Peterson In the '' Brown-Peterson experiment'', participants are briefly presented with a trigram and in one particular version of the experiment, they are then given a distractor task, asking them to identify whether a sequence of words is in fact words, or non-words (due to being misspelled, etc.). After the distractor task, they are asked to recall the trigram from before the distractor task. In theory, the longer the distractor task, the harder it will be for participants to correctly recall the trigram. This experiment focuses on human

short-term memory Short-term memory (or "primary" or "active memory") is the capacity for holding a small amount of information in an active, readily available state for a short interval. For example, short-term memory holds a phone number that has just been recit ...

. Memory span During the ''

memory span In psychology and neuroscience, memory span is the longest list of items that a person can repeat back in correct order immediately after presentation on 50% of all trials. Items may include words, numbers, or letters. The task is known as ''digit s ...

experiment'', each subject is presented with a sequence of stimuli of the same kind; words depicting objects, numbers, letters that sound similar, and letters that sound dissimilar. After being presented with the stimuli, the subject is asked to recall the sequence of stimuli that they were given in the exact order in which it was given. In one particular version of the experiment, if the subject recalled a list correctly, the list length was increased by one for that type of material, and vice versa if it was recalled incorrectly. The theory is that people have a memory span of about seven items for numbers, the same for letters that sound dissimilar and short words. The memory span is projected to be shorter with letters that sound similar and with longer words. Visual search In one version of the '' visual search experiment'', a participant is presented with a window that displays circles and squares scattered across it. The participant is to identify whether there is a green circle on the window. In the ''featured'' search, the subject is presented with several trial windows that have blue squares or circles and one green circle or no green circle in it at all. In the ''

conjunctive The subjunctive (also known as conjunctive in some languages) is a grammatical mood, a feature of the utterance that indicates the speaker's attitude towards it. Subjunctive forms of verbs are typically used to express various states of unreality s ...

'' search, the subject is presented with trial windows that have blue circles or green squares and a present or absent green circle whose presence the participant is asked to identify. What is expected is that in the feature searches, reaction time, that is the time it takes for a participant to identify whether a green circle is present or not, should not change as the number of distractors increases. Conjunctive searches where the target is absent should have a longer reaction time than the conjunctive searches where the target is present. The theory is that in feature searches, it is easy to spot the target, or if it is absent, because of the difference in color between the target and the distractors. In conjunctive searches where the target is absent, reaction time increases because the subject has to look at each shape to determine whether it is the target or not because some of the distractors if not all of them, are the same color as the target stimuli. Conjunctive searches where the target is present take less time because if the target is found, the search between each shape stops. Knowledge representation The semantic network of

knowledge representation Knowledge representation and reasoning (KRR, KR&R, KR²) is the field of artificial intelligence (AI) dedicated to representing information about the world in a form that a computer system can use to solve complex tasks such as diagnosing a medic ...

systems have been studied in various paradigms. One of the oldest paradigms is the

leveling Levelling or leveling (American English; see spelling differences) is a branch of surveying, the object of which is to establish or verify or measure the height of specified points relative to a datum. It is widely used in geodesy and cartogra ...

and sharpening of stories as they are repeated from memory studied by

Bartlett Bartlett may refer to: Places *Bartlett Bay, Canada, Arctic waterway * Wharerata, New Zealand, also known as Bartletts United States * Bartlett, Illinois ** Bartlett station, a commuter railroad station * Bartlett, Iowa Bartlett is an uninc ...

. The

semantic differential The semantic differential (SD) is a measurement scale designed to measure a person's subjective perception of, and affective reactions to, the properties of concepts, objects, and events by making use of a set of bipolar scales. The SD is used to a ...

used factor analysis to determine the main meanings of words, finding that

value Value or values may refer to: Ethics and social * Value (ethics) wherein said concept may be construed as treating actions themselves as abstract objects, associating value to them ** Values (Western philosophy) expands the notion of value beyo ...

or "goodness" of words is the first factor. More controlled experiments examine the categorical relationships of words in

free recall Free recall is a common task in the psychological study of memory. In this task, participants study a list of items on each trial, and then are prompted to recall the items in any order. Items are usually presented one at a time for a short du ...

. The hierarchical structure of words has been explicitly mapped in George Miller's Wordnet. More dynamic models of semantic networks have been created and tested with

neural network A neural network is a network or circuit of biological neurons, or, in a modern sense, an artificial neural network, composed of artificial neurons or nodes. Thus, a neural network is either a biological neural network, made up of biological ...

experiments based on computational systems such as latent semantic analysis (LSA), Bayesian analysis, and multidimensional factor analysis. The semantics (meaning) of words is studied by all the disciplines of cognitive science.

Metacognition

Improving cognition

Physical exercise

Aerobic and

anaerobic exercise Anaerobic exercise is a type of exercise that breaks down glucose in the body without using oxygen; ''anaerobic'' means "without oxygen". In practical terms, this means that anaerobic exercise is more intense, but shorter in duration than aerobi ...

have been studied concerning cognitive improvement. There appear to be short-term increases in attention span, verbal and visual memory in some studies. However, the effects are transient and diminish over time, after cessation of the physical activity.

Dietary supplements

Studies evaluating phytoestrogen, blueberry supplementation and antioxidants showed minor increases in cognitive function after supplementation but no significant effects compared to placebo.

Pleasurable social stimulation

Exposing individuals with cognitive impairment (i.e., Dementia) to daily activities designed to stimulate thinking and memory in a social setting, seems to improve cognition. Although study materials are small, and larger studies need to confirm the results, the effect of social cognitive stimulation seems to be larger than the effects of some drug treatments.

Other methods

Transcranial magnetic stimulation (TMS) has been shown to improve cognition in individuals without dementia 1 month after treatment session compared to before treatment. The effect was not significantly larger compared to placebo. Computerized cognitive training, utilising a computer based training regime for different cognitive functions has been examined in a clinical setting but no lasting effects has been shown.

References

External links

''Cognition''
An international journal publishing theoretical and experimental papers on the study of the mind.
Information on music cognition, University of Amsterdam

Cognitie.NL
Information on cognition research, Netherlands Organisation for Scientific Research (NWO) and University of Amsterdam (UvA) * Emotional and Decision Making Lab, Carnegie Mellon
EDM Lab

The Limits of Human Cognition
– an article describing the evolution of mammals' cognitive abilities

The limits of intelligence
Douglas Fox, '' Scientific American'', 14 June 14, 2011. {{Authority control * * Mental processes Thought