The following is a list of notable unsolved problems in

neuroscience Neuroscience is the scientific study of the nervous system (the brain, spinal cord, and peripheral nervous system), its functions, and its disorders. It is a multidisciplinary science that combines physiology, anatomy, molecular biology, ...

. A problem is considered unsolved if no answer is known or if there is significant disagreement among experts about a proposed solution.

Consciousness

Consciousness Consciousness, at its simplest, is awareness of a state or object, either internal to oneself or in one's external environment. However, its nature has led to millennia of analyses, explanations, and debate among philosophers, scientists, an ...

: **How can consciousness be defined? **What is the neural basis of

subjective experience In philosophy of mind, qualia (; singular: quale ) are defined as instances of Subjectivity, subjective, consciousness, conscious experience. The term ''qualia'' derives from the Latin neuter plural form (''qualia'') of the Latin adjective '':wi ...

, cognition, wakefulness,

alertness Alertness is a state of active attention characterized by high sensory awareness. Someone who is alert is vigilant and promptly meets danger or emergency, or is quick to perceive and act. Alertness is a psychological and physiological state. Lac ...

arousal Arousal is the physiology, physiological and psychology, psychological state of being awoken or of Five senses, sense organs stimulated to a point of perception. It involves activation of the ascending reticular activating system (ARAS) in the hu ...

, and

attention Attention or focus, is the concentration of awareness on some phenomenon to the exclusion of other stimuli. It is the selective concentration on discrete information, either subjectively or objectively. William James (1890) wrote that "Atte ...

? ***

Binding problem The unity of consciousness and (cognitive) binding problem is the problem of how objects, background, and abstract or emotional features are combined into a single experience. The binding problem refers to the overall encoding of our brain circuit ...

: How exactly is it that objects, background, and abstract or emotional features are combined into a single experience? ***What is the neural basis of self? ** Quantum mind: Do

quantum mechanical Quantum mechanics is the fundamental physical theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is the foundation of a ...

phenomena, such as entanglement and

superposition In mathematics, a linear combination or superposition is an expression constructed from a set of terms by multiplying each term by a constant and adding the results (e.g. a linear combination of ''x'' and ''y'' would be any expression of the form ...

, play an important part in the brain's function and can it explain critical aspects of

consciousness Consciousness, at its simplest, is awareness of a state or object, either internal to oneself or in one's external environment. However, its nature has led to millennia of analyses, explanations, and debate among philosophers, scientists, an ...

? **Is there a "

hard problem of consciousness In the philosophy of mind, the hard problem of consciousness is to explain why and how humans and other organisms have qualia, phenomenal consciousness, or subjective experience. It is contrasted with the "easy problems" of explaining why and how ...

"? ***If so, how is it solved? ***

Vertiginous question Benj Hellie's vertiginous question asks why, of all the subjects of experience out there, ''this'' one—the one corresponding to the human being referred to as Benj Hellie—is the one whose experiences are ''lived''? (The reader is supposed to ...

: Why is it that a specific subject of experience is "live" from a given perspective? **What, if anything, is the function of consciousness? ***

Problem of mental causation The problem of mental causation is a conceptual issue in the philosophy of mind. That problem, in short, is how to account for the common sense idea that intentional thoughts or intentional mental states are causes of intentional actions. The pro ...

: How exactly do mental states cause intentional actions to happen? **What is the nature and mechanism behind

near-death experience A near-death experience (NDE) is a profound personal experience associated with death or impending death, which researchers describe as having similar characteristics. When positive, which the great majority are, such experiences may encompa ...

s? ***How can death be defined? Can consciousness exist after death? ***If consciousness is generated by brain activity, then how do some patients with physically deteriorated brains suddenly gain a brief moment of restored consciousness prior to death, a phenomenon known as

terminal lucidity Terminal lucidity (also known as rallying, terminal rally, the rally, end-of-life-experience, energy surge, the surge, or pre-mortem surge) is an unexpected return of consciousness, mental clarity, or memory shortly before death in individuals wit ...

? **What beings are conscious? ***

Animal consciousness Animal consciousness, or animal awareness, is the Quality (philosophy), quality or state of self-awareness within an animal, or of being aware of an external object or something within itself. In humans, consciousness has been defined as: senti ...

: What animals or other lifeforms have conscious experience? ***Are philosophical zombies possible? ***How might it be possible to test whether a being has qualia or not? * Problem of representation: How exactly does the

mind The mind is that which thinks, feels, perceives, imagines, remembers, and wills. It covers the totality of mental phenomena, including both conscious processes, through which an individual is aware of external and internal circumstances ...

function (or how does the brain interpret and represent information about the world)? ** Bayesian mind: Does the mind make sense of the world by constantly trying to make predictions according to the rules of

Bayesian probability Bayesian probability ( or ) is an interpretation of the concept of probability, in which, instead of frequency or propensity of some phenomenon, probability is interpreted as reasonable expectation representing a state of knowledge or as quant ...

? **

Computational theory of mind In philosophy of mind, the computational theory of mind (CTM), also known as computationalism, is a family of views that hold that the human mind is an information processing system and that cognition and consciousness together are a form of comp ...

: Is the mind a symbol manipulation system, operating on a

model of computation In computer science, and more specifically in computability theory and computational complexity theory, a model of computation is a model which describes how an output of a mathematical function is computed given an input. A model describes how ...

, similar to a computer? **

Connectionism Connectionism is an approach to the study of human mental processes and cognition that utilizes mathematical models known as connectionist networks or artificial neural networks. Connectionism has had many "waves" since its beginnings. The first ...

: Can the mind be explained by mathematical models known as

artificial neural network In machine learning, a neural network (also artificial neural network or neural net, abbreviated ANN or NN) is a computational model inspired by the structure and functions of biological neural networks. A neural network consists of connected ...

s? **

Embodied cognition Embodied cognition represents a diverse group of theories which investigate how cognition is shaped by the bodily state and capacities of the organism. These embodied factors include the motor system, the perceptual system, bodily interactions wi ...

: Is the cognition of an organism affected by the organism's entire body (rather than just simply its brain), including its interactions with the environment? ** Extended mind thesis: Does the mind not only exist in the brain, but also functions in the outside world by using physical objects as

mental process Cognition is 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, thought, i ...

es? Or just as prosthetic limbs can become part of the body, can handwritten notes become part of the mind? ** Mind-body dualism: Is the mind distinct from the body? **

Modularity of mind Modularity of mind is the notion that a mind may, at least in part, be composed of innate neural structures or mental modules which have distinct, established, and evolutionarily developed functions. However, different definitions of "module" have ...

: Is the mind composed of distinct modules, each evolved to solve a specific evolutionary problem from the past? ** Dynamical neuroscience: Is the mind a

dynamical system In mathematics, a dynamical system is a system in which a Function (mathematics), function describes the time dependence of a Point (geometry), point in an ambient space, such as in a parametric curve. Examples include the mathematical models ...

Sensation, perception and movement

Perception Perception () is the organization, identification, and interpretation of sensory information in order to represent and understand the presented information or environment. All perception involves signals that go through the nervous syste ...

: **How does the

brain The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for ...

transfer sensory information into coherent, private percepts? **What are the

rules Rule or ruling may refer to: Human activity * The exercise of political or personal control by someone with authority or power * Business rule, a rule pertaining to the structure or behavior internal to a business * School rule, a rule tha ...

by which perception is organized? **What are the features/objects that constitute our perceptual experience of internal and external events? **How are the

senses A sense is a biological system used by an organism for sensation, the process of gathering information about the surroundings through the detection of stimuli. Although, in some cultures, five human senses were traditionally identified as su ...

integrated? **What is the relationship between subjective experience and the physical world?

Learning and memory

Learning Learning is the process of acquiring new understanding, knowledge, behaviors, skills, value (personal and cultural), values, Attitude (psychology), attitudes, and preferences. The ability to learn is possessed by humans, non-human animals, and ...

and

memory Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembe ...

: **Where do our memories get stored and how are they retrieved again? **How can learning be improved? **What is the difference between

explicit Explicit refers to something that is specific, clear, or detailed. It can also mean: * Explicit knowledge, knowledge that can be readily articulated, codified and transmitted to others * Explicit (text), the final words of a text; contrast with inc ...

and implicit memories? **What molecule is responsible for synaptic tagging? *

Neuroplasticity Neuroplasticity, also known as neural plasticity or just plasticity, is the ability of neural networks in the brain to change through neurogenesis, growth and reorganization. Neuroplasticity refers to the brain's ability to reorganize and rewir ...

: How

plastic Plastics are a wide range of synthetic polymers, synthetic or Semisynthesis, semisynthetic materials composed primarily of Polymer, polymers. Their defining characteristic, Plasticity (physics), plasticity, allows them to be Injection moulding ...

is the mature brain? *

Cognition Cognition is 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, thought, ...

and decisions: **How and where does the brain evaluate reward value and effort (

cost Cost is the value of money that has been used up to produce something or deliver a service, and hence is not available for use anymore. In business, the cost may be one of acquisition, in which case the amount of money expended to acquire it i ...

) to modulate

behavior Behavior (American English) or behaviour (British English) is the range of actions of Individual, individuals, organisms, systems or Artificial intelligence, artificial entities in some environment. These systems can include other systems or or ...

? **How does previous experience alter perception and behavior? **What are the genetic and environmental contributions to brain function?

Language

Language Language is a structured system of communication that consists of grammar and vocabulary. It is the primary means by which humans convey meaning, both in spoken and signed language, signed forms, and may also be conveyed through writing syste ...

: **How is it implemented neurally? **What is the basis of

semantic Semantics is the study of linguistic Meaning (philosophy), meaning. It examines what meaning is, how words get their meaning, and how the meaning of a complex expression depends on its parts. Part of this process involves the distinction betwee ...

meaning? *

Language acquisition Language acquisition is the process by which humans acquire the capacity to perceive and comprehend language. In other words, it is how human beings gain the ability to be aware of language, to understand it, and to produce and use words and s ...

: ** Controversy: infant

language acquisition Language acquisition is the process by which humans acquire the capacity to perceive and comprehend language. In other words, it is how human beings gain the ability to be aware of language, to understand it, and to produce and use words and s ...

/first-language acquisition. How are infants able to learn language? One line of debate is between two points of view: that of

psychological nativism In the field of psychology, nativism is the view that certain skills or abilities are "native" or hard-wired into the brain at birth. This is in contrast to the "blank slate" or view, which states that the brain has inborn capabilities for learni ...

, i.e., the language ability is somehow "hardwired" in the human brain, and usage based theories of language, according to which language emerges through to brain's interaction with environment and activated by general dispositions for social interaction and communication, abstract symbolic thought and pattern recognition and inference. ** Is the human ability to use syntax based on innate mental structures or is syntactic speech the function of intelligence and interaction with other humans? The question is closely related to those of language emergence and acquisition. ** Is there a

language acquisition device The Language Acquisition Device (LAD) is a claim from language acquisition research proposed by Noam Chomsky in the 1960s. The LAD concept is a purported instinctive mental capacity which enables an infant to acquire and produce language. It is a ...

: How localized is language in the brain? Is there a particular area in the brain responsible for the development of language abilities or is it only partially localized? ** What fundamental reasons explain why ultimate attainment in

second-language acquisition Second-language acquisition (SLA), sometimes called second-language learning—otherwise referred to as L2 (language 2) acquisition, is the process of learning a language other than one's native language (L1). SLA research examines how learners ...

is typically some way short of the

native speaker Native Speaker may refer to: * ''Native Speaker'' (novel), a 1995 novel by Chang-Rae Lee * ''Native Speaker'' (album), a 2011 album by Canadian band Braids * Native speaker, a person using their first language or mother tongue * Native spea ...

's ability, with learners varying widely in performance? ** What are the optimal ways to achieve successful

? ** Animals and language: How much human language can animals be taught to use? How much of animal communication can be said to have the same properties as human language (e.g.

compositionality In semantics, mathematical logic and related disciplines, the principle of compositionality is the principle that the meaning of a complex expression is determined by the meanings of its constituent expressions and the rules used to combine them. ...

of bird calls as

syntax In linguistics, syntax ( ) is the study of how words and morphemes combine to form larger units such as phrases and sentences. Central concerns of syntax include word order, grammatical relations, hierarchical sentence structure (constituenc ...

)? ** What role does linguistic

intuition Intuition is the ability to acquire knowledge without recourse to conscious reasoning or needing an explanation. Different fields use the word "intuition" in very different ways, including but not limited to: direct access to unconscious knowledg ...

play, how is it formed and how does it function? Is it closely linked to exposure to a unique set of different experiences and their contexts throughout one's personal life? *

Linguistic relativity Linguistic relativity asserts that language influences worldview or cognition. One form of linguistic relativity, linguistic determinism, regards peoples' languages as determining and influencing the scope of cultural perceptions of their surro ...

: What are the relations between grammatical patterns and cognitive habits of speakers of different languages? Does language use train or habituate speakers to certain cognitive habits that differ between speakers of different languages? Are effects of linguistic relativity caused by grammar structures or by cultural differences that underlie differences in language use.

Mind-body connection

Free will Free will is generally understood as the capacity or ability of people to (a) choice, choose between different possible courses of Action (philosophy), action, (b) exercise control over their actions in a way that is necessary for moral respon ...

, particularly the

neuroscience of free will The neuroscience of free will, a part of neurophilosophy, is the study of topics related to free will (including Volition (psychology), volition and the sense of agency), using neuroscience and the analysis of how findings from such studies may ...

. **

** ** ** *

Sleep Sleep is a state of reduced mental and physical activity in which consciousness is altered and certain Sensory nervous system, sensory activity is inhibited. During sleep, there is a marked decrease in muscle activity and interactions with th ...

: **What is the biological function of sleep? **Why do we

dream A dream is a succession of images, ideas, emotions, and sensation (psychology), sensations that usually occur involuntarily in the mind during certain stages of sleep. Humans spend about two hours dreaming per night, and each dream lasts around ...

? **What are the underlying brain mechanisms? **What is its relation to

anesthesia Anesthesia (American English) or anaesthesia (British English) 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 prev ...

Computational neuroscience

: What are the limits of understanding thinking as a form of computing? *

Computational neuroscience Computational neuroscience (also known as theoretical neuroscience or mathematical neuroscience) is a branch of neuroscience which employs mathematics, computer science, theoretical analysis and abstractions of the brain to understand th ...

: **How important is the precise timing of action potentials for information processing in the neocortex? **Is there a canonical computation performed by cortical columns? **How is information in the brain processed by the collective dynamics of large neuronal circuits? **What level of simplification is suitable for a description of information processing in the brain? **What is the neural code? *How do

general anesthetics General anaesthetics (or anesthetics) are often defined as compounds that induce a loss of consciousness in humans or loss of righting reflex in animals. Clinical definitions are also extended to include an induced coma that causes lack of aware ...

work? * *The

emergence In philosophy, systems theory, science, and art, emergence occurs when a complex entity has properties or behaviors that its parts do not have on their own, and emerge only when they interact in a wider whole. Emergence plays a central rol ...

and

evolution Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

intelligence Intelligence has been defined in many ways: the capacity for abstraction, logic, understanding, self-awareness, learning, emotional knowledge, reasoning, planning, creativity, critical thinking, and problem-solving. It can be described as t ...

: What are the laws and mechanisms - of new

idea In philosophy and in common usage, an idea (from the Greek word: ἰδέα (idea), meaning 'a form, or a pattern') is the results of thought. Also in philosophy, ideas can also be mental representational images of some object. Many philosophe ...

emergence (

insight Insight is the understanding of a specific causality, cause and effect within a particular context. The term insight can have several related meanings: *a piece of information *the act or result of understanding the inner nature of things or of se ...

, creativity synthesis,

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

, eureka); development (evolution) of an individual

in the

ontogenesis Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the egg to adult. The term can also be used to refer to the stu ...

, etc.?

References

External links

The Human Brain Project Homepage
* * {{DEFAULTSORT:Unsolved problems in neuroscience

Neuroscience Neuroscience is the scientific study of the nervous system (the brain, spinal cord, and peripheral nervous system), its functions, and its disorders. It is a multidisciplinary science that combines physiology, anatomy, molecular biology, ...

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