Malleable intelligence
Encyclopedia
Malleability of intelligence describes the processes by which human intelligence
may be augmented through changes in neuroplasticity
. These changes may come as a result of genetics
, pharmacological factors, psychological factors, behavior
, or environmental conditions
. In general, the majority of plasticity
as it relates to intelligence occurs at either the onset of development, during the critical period
, or during old age. Malleable intelligence may refer to changes in cognitive skills
, memory
, reasoning, or muscle memory
related motor skills.
Charles Spearman
, who coined the general intelligence factor
"g", described intelligence as one's ability to adapt to his environment with a set of useful skills including reasoning and understanding patterns and relationships. He believed individuals highly developed in one intellectual ability tended to be highly developed at other intellectual abilities. A more intelligent individual was thought to be able to more easily "accommodate" experiences into existing cognitive structures to develop structures more compatible with environmental stimuli.
In general, intelligence is thought to be attributed to both genetic and environmental factors, but the extent to which each plays a key role is highly disputed. Studies of identical and non-identical twins raised separately and together show a strong correlation between child IQ and socio-economic level
of the parents. Children raised in lower class families tend to score lower on intelligence tests when compared to children raised in both middle and upper class families. However, there is no difference in intelligence scores between children raised in middle versus upper class families.
is founded in the degree of connectivity of neurons in the brain and the varying amounts of white
and grey
matter. Studies show that intelligence is positively correlated with total cerebral volume. In particular, the volume of the cortical
grey matter in the prefrontal region
plays a large part in both brain volume and intelligence. While it is true that the number of neurons in the brain actually decreases throughout development, as neural connections grow and the pathways become more efficient, the supporting structures in the brain increase. This increase in supporting tissues, which include myelination, blood vessels, and glial cells, leads to an increase in overall brain size. When brain circumference and IQ were compared in 9 year olds, a positive correlation was found between the two. An increase of 2.87 IQ points occurred for each standard deviation
increase in brain circumference
.
, defined as the beginning years of brain development, is essential to intellectual development, as the brain optimizes the overproduction of synapses present at birth. During the critical period
, the neuronal pathways are refined based on which synapses are active and receiving transmission. It is a "use it or lose it" phenomenon. The more cortical thinning that occurs, the higher the IQ.
On a chemical level, BDNF
activates the nucleus basalis, a part of the brain that focuses attention and remains activated throughout the critical period. BDNF also consolidates connections between neurons that fire together in order to wire them together and provide more reliable firing in the future. At the end of the critical period
, BDNF
deactivates the nucleus basalis. One of the problems in autism
is that BDNF
is released prematurely, causing all connections to be reinforced. BDNF then prematurely ends the critical period and seals in place these undifferentiated connections of brain maps. Merzenich
and Kilgard tested the effectiveness of the nucleus basalis to control the critical period by electrically stimulating the nucleus basalis of rats and exposing the rats to a continual frequency of 9 Hz. Merzenich discovered that the brain map for the 9 Hz frequency had been massively expanded. This research raises further questions on the ability to turn on/off the nucleus basalis and thus the critical period
through electrical or pharmacological means.
(LTP). It refers to a change in neural connectivity as a result of high activation on both sides of a synaptic cleft. This change in neural connectivity allows information to be more easily processed, as the neural connection associated with that information becomes stronger through LTP. Other forms of plasticity involve the growth of new neurons, the growth of new connections between neurons, and the selective elimination of such connection, called "dendritic pruning" .
due to their genetic makeups, which affects their ability to adapt to conditions in their environments and effectively learn from experiences. The degree to which intelligence can be linked to genetic heritability
increases with age. A study of Dutch twins concludes that intelligence of a 5 year old is 26% heritability, while the intelligence of a 12 year old is 64% based on heritability
. Structurally, genetic influences explain 77-88% of the variance in the thickness of the mid-sagittal area
of the corpus callosum
, the volume of the caudate nucleus
, and the volumes of the parietal
and temporal
lobes.
and glutamatergic systems in the brain serve an important role in learning, memory, and the developmental organization of neuronal circuitry. These systems help to capitalize on the critical period and organize synaptic transmission. Autism
and other learning disabilities have been targeted with drugs focusing on cholinergic and glutamatergic transmission. These drugs increase the amount of acetylcholine
present in the brain by increasing the production of acetylcholine precursors, as well as inhibiting acetylcholine degradation by cholinesterases. By focusing on heightening the activity of this system, the brain's responsiveness to activity-dependent plasticity
is improved. Specifically, glutamatergic drugs may reduce the threshold for LTP
, promote more normal dendritic spine
morphology, and retain a greater number of useful synaptic connections. Cholinergic drugs may reconnect the basal forebrain
with the cortex
and hippocampus
, connections that are often disrupted in patients with learning disorders.
show impaired corticolimbic connectivity in development. Early chronic stress is defined as inconsistent or inadequate care-giving and disruption to early rearing environment. These children showed decreased cognitive function, especially in fluid cognition
, or the ability to effectively utilize working memory
. The lack of connectivity between the limbic system
and the prefrontal cortex
can be blamed for this deficiency.
In addition to stress
, perceptions of intelligence can also play a negative role in cognitive development
. A study at Columbia University
showed entity theorists, or people with a belief in fixed intelligence, showed less improvement on cognitive testing after receiving initial feedback than incremental theorists, or people with a belief in malleable intelligence. Entity theorists focus on performance goals and proving their intelligence, which makes them vulnerable to negative feedback
and failure. This is in contrast to incremental theorists, who focus on learning goals and rebound well from occasional failure or feedback. Incremental theorists focus on challenging tasks to expand intelligence instead of working to prove their own intelligence. Thus, a variety of psychological factors can inhibit one's propensity to expand his intelligence.
. These new branches often lead to greater mental processing in different areas. For instance, use of the popular Fast ForWord
learning system has been shown to increase visually based IQ. As a result, participants' verbal reading scores also improved. Thus, mental processing generally improved due to an improvement in temporal
processing of the visual field
. Other programs similar to Fast ForWord
have boasted similar results, but recent studies show that the cognitive processing improvements gained from these programs diminish after instruction has ended. In the end, the program intervention may help expedite the neural development of children with less neural plasticity, but after the intervention is removed, children with greater neural plasticity not involved in the program will eventually meet and surpass the program participants.
is a time of neural pruning and great intellectual development. The time scale for humans to learn language without an accent begins in infancy and ends around 8 years old. Languages learned after 8 years old will be spoken with an accent and will not be processed in the same part of the brain as the native language. Similarly, a study was conducted in which children were exposed to Zulu
before the age of 2. The children could discriminate non-native contrasts that adults had difficulty perceiving. Thus, the critical period prepares children to process numerous types of stimulus input that the adult brain cannot process.
Another example of the critical period playing an important role in development is with eyesight and cataracts. Infants born with cataracts will become blind if the surgery to remove the cataract
is not done during the critical period
. After the critical period, the brain map
for eyesight will have rewired itself, and the child will be blind. Similarly, rats reared in the dark will maintain the critical period for eyesight until placed in a lit environment, when the vision is corrected. However, the extension of the critical period does not last infinitely. Eventually, without light input, the rats will go blind as their visual cortex is overcome by other neural connections via plasticity.
In regards to cognitive processing, individuals who are considered "genius
" often began exploring their fields well before maturity. One obvious example is Albert Einstein
, who began studying the universe at age 5 and learned advanced math at age 12. The ability of these geniuses to understand their field is due largely in part to their interest at a young age, during the ongoing critical period. Interestingly, another factor that has a strong correlation with intelligence is breast feeding of infants. Even after normalizing for mother's intelligence, age, education, socio-economic status, and mood fluctuations during pregnancy, breast fed infants show greater scores on cognitive functioning tests, which persisted throughout development.
in children 4 and 6 years old . Executive attention refers to the self-regulation of cognition
and emotion
. The training focused on developing the child's ability to track moving objects, anticipate events, memorize stimuli over brief periods of time, and inhibit learned responses. This training improved intelligence in the 4-year-old but not the 6-year-old group. The training had no effect on a test of executive attention, the "Attention Network Test".
is necessary, but taking extra won't help.
Other environmental factors, like disease, play a significant role in intellectual development. A study from Norway by Eriksen et al. concluded that infants born just after the Hong Kong Flu
pandemic during July–October 1970 scored lower on cognitive tests than others born in 1970 when normalized for parental education, paternal age, and premature percentages. Maternal flu can cause both transient breathing and eating difficulties, both of which have long term effects on the intellectual development of the developing fetus
.
Intelligence
Intelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....
may be augmented through changes in neuroplasticity
Neuroplasticity
Neuroplasticity is a non-specific neuroscience term referring to the ability of the brain and nervous system in all species to change structurally and functionally as a result of input from the environment. Plasticity occurs on a variety of levels, ranging from cellular changes involved in...
. These changes may come as a result of genetics
Genetics
Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....
, pharmacological factors, psychological factors, behavior
Behavior
Behavior or behaviour refers to the actions and mannerisms made by organisms, systems, or artificial entities in conjunction with its environment, which includes the other systems or organisms around as well as the physical environment...
, or environmental conditions
Environment (biophysical)
The biophysical environment is the combined modeling of the physical environment and the biological life forms within the environment, and includes all variables, parameters as well as conditions and modes inside the Earth's biosphere. The biophysical environment can be divided into two categories:...
. In general, the majority of plasticity
Plasticity
Plasticity may refer to:Science* Plasticity , in physics and engineering, plasticity is the propensity of a material to undergo permanent deformation under load...
as it relates to intelligence occurs at either the onset of development, during the critical period
Critical period
This article is about a critical period in an organism's or person's development. See also America's Critical Period.In general, a critical period is a limited time in which an event can occur, usually to result in some kind of transformation...
, or during old age. Malleable intelligence may refer to changes in cognitive skills
Cognition
In science, cognition refers to mental processes. These processes include attention, remembering, producing and understanding language, solving problems, and making decisions. Cognition is studied in various disciplines such as psychology, philosophy, linguistics, and computer science...
, memory
Memory
In psychology, memory is an organism's ability to store, retain, and recall information and experiences. Traditional studies of memory began in the fields of philosophy, including techniques of artificially enhancing memory....
, reasoning, or muscle memory
Muscle memory
Muscle memory has been used synonymously with motor learning, which is a form of procedural memory that involves consolidating a specific motor task into memory through repetition. When a movement is repeated over time, a long-term muscle memory is created for that task, eventually allowing it to...
related motor skills.
Charles Spearman
Charles Spearman
Charles Edward Spearman, FRS was an English psychologist known for work in statistics, as a pioneer of factor analysis, and for Spearman's rank correlation coefficient...
, who coined the general intelligence factor
General intelligence factor
The g factor, where g stands for general intelligence, is a statistic used in psychometrics to model the mental ability underlying results of various tests of cognitive ability...
"g", described intelligence as one's ability to adapt to his environment with a set of useful skills including reasoning and understanding patterns and relationships. He believed individuals highly developed in one intellectual ability tended to be highly developed at other intellectual abilities. A more intelligent individual was thought to be able to more easily "accommodate" experiences into existing cognitive structures to develop structures more compatible with environmental stimuli.
In general, intelligence is thought to be attributed to both genetic and environmental factors, but the extent to which each plays a key role is highly disputed. Studies of identical and non-identical twins raised separately and together show a strong correlation between child IQ and socio-economic level
Socioeconomic status
Socioeconomic status is an economic and sociological combined total measure of a person's work experience and of an individual's or family’s economic and social position in relation to others, based on income, education, and occupation...
of the parents. Children raised in lower class families tend to score lower on intelligence tests when compared to children raised in both middle and upper class families. However, there is no difference in intelligence scores between children raised in middle versus upper class families.
Definitions
- IntelligenceIntelligenceIntelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....
: a very general capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly and learn from experience.
- Critical periodCritical periodThis article is about a critical period in an organism's or person's development. See also America's Critical Period.In general, a critical period is a limited time in which an event can occur, usually to result in some kind of transformation...
: a restricted developmental period during which the nervous system is particularly sensitive to the effects of experience .
Neuroscience basis
The biological basis of intelligenceIntelligence
Intelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....
is founded in the degree of connectivity of neurons in the brain and the varying amounts of white
White matter
White matter is one of the two components of the central nervous system and consists mostly of myelinated axons. White matter tissue of the freshly cut brain appears pinkish white to the naked eye because myelin is composed largely of lipid tissue veined with capillaries. Its white color is due to...
and grey
Grey matter
Grey matter is a major component of the central nervous system, consisting of neuronal cell bodies, neuropil , glial cells and capillaries. Grey matter contains neural cell bodies, in contrast to white matter, which does not and mostly contains myelinated axon tracts...
matter. Studies show that intelligence is positively correlated with total cerebral volume. In particular, the volume of the cortical
Cortex
Cortex may refer to:-Sciences:* Cortex , the outer portion of the stem or root of a plant...
grey matter in the prefrontal region
Prefrontal cortex
The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.This brain region has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior...
plays a large part in both brain volume and intelligence. While it is true that the number of neurons in the brain actually decreases throughout development, as neural connections grow and the pathways become more efficient, the supporting structures in the brain increase. This increase in supporting tissues, which include myelination, blood vessels, and glial cells, leads to an increase in overall brain size. When brain circumference and IQ were compared in 9 year olds, a positive correlation was found between the two. An increase of 2.87 IQ points occurred for each standard deviation
Standard deviation
Standard deviation is a widely used measure of variability or diversity used in statistics and probability theory. It shows how much variation or "dispersion" there is from the average...
increase in brain circumference
Circumference
The circumference is the distance around a closed curve. Circumference is a special perimeter.-Circumference of a circle:The circumference of a circle is the length around it....
.
Importance of critical period
The brain grows rapidly for the first five years of human development. At age five, the human brain is 90% of its total size. Then the brain finishes growing gradually until age twenty. From start to finish, the brain increases in size by over 300% from birth. The critical periodCritical period
This article is about a critical period in an organism's or person's development. See also America's Critical Period.In general, a critical period is a limited time in which an event can occur, usually to result in some kind of transformation...
, defined as the beginning years of brain development, is essential to intellectual development, as the brain optimizes the overproduction of synapses present at birth. During the critical period
Critical period
This article is about a critical period in an organism's or person's development. See also America's Critical Period.In general, a critical period is a limited time in which an event can occur, usually to result in some kind of transformation...
, the neuronal pathways are refined based on which synapses are active and receiving transmission. It is a "use it or lose it" phenomenon. The more cortical thinning that occurs, the higher the IQ.
On a chemical level, BDNF
Brain-derived neurotrophic factor
Brain-derived neurotrophic factor, also known as BDNF, is a protein that, in humans, is encoded by the BDNF gene. BDNF is a member of the "neurotrophin" family of growth factors, which are related to the canonical "Nerve Growth Factor", NGF...
activates the nucleus basalis, a part of the brain that focuses attention and remains activated throughout the critical period. BDNF also consolidates connections between neurons that fire together in order to wire them together and provide more reliable firing in the future. At the end of the critical period
Critical period
This article is about a critical period in an organism's or person's development. See also America's Critical Period.In general, a critical period is a limited time in which an event can occur, usually to result in some kind of transformation...
, BDNF
Brain-derived neurotrophic factor
Brain-derived neurotrophic factor, also known as BDNF, is a protein that, in humans, is encoded by the BDNF gene. BDNF is a member of the "neurotrophin" family of growth factors, which are related to the canonical "Nerve Growth Factor", NGF...
deactivates the nucleus basalis. One of the problems in autism
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
is that BDNF
Brain-derived neurotrophic factor
Brain-derived neurotrophic factor, also known as BDNF, is a protein that, in humans, is encoded by the BDNF gene. BDNF is a member of the "neurotrophin" family of growth factors, which are related to the canonical "Nerve Growth Factor", NGF...
is released prematurely, causing all connections to be reinforced. BDNF then prematurely ends the critical period and seals in place these undifferentiated connections of brain maps. Merzenich
Merzenich
Merzenich is a municipality in the district of Düren in the state of North Rhine-Westphalia, Germany. It is located approx. 4 km north-east of Düren....
and Kilgard tested the effectiveness of the nucleus basalis to control the critical period by electrically stimulating the nucleus basalis of rats and exposing the rats to a continual frequency of 9 Hz. Merzenich discovered that the brain map for the 9 Hz frequency had been massively expanded. This research raises further questions on the ability to turn on/off the nucleus basalis and thus the critical period
Critical period
This article is about a critical period in an organism's or person's development. See also America's Critical Period.In general, a critical period is a limited time in which an event can occur, usually to result in some kind of transformation...
through electrical or pharmacological means.
Neural plasticity
Neural plasticity refers to any change in the structure of the neural network that forms the central nervous system. Neural plasticity is the neuronal basis for changes in how the mind works, including learning, the formation of memory, and changes in intelligence. One well-studied form of plasticity is Long-Term PotentiationLong-term potentiation
In neuroscience, long-term potentiation is a long-lasting enhancement in signal transmission between two neurons that results from stimulating them synchronously. It is one of several phenomena underlying synaptic plasticity, the ability of chemical synapses to change their strength...
(LTP). It refers to a change in neural connectivity as a result of high activation on both sides of a synaptic cleft. This change in neural connectivity allows information to be more easily processed, as the neural connection associated with that information becomes stronger through LTP. Other forms of plasticity involve the growth of new neurons, the growth of new connections between neurons, and the selective elimination of such connection, called "dendritic pruning" .
Genetic factors of intelligence
Humans have varying degrees of neuroplasticityNeuroplasticity
Neuroplasticity is a non-specific neuroscience term referring to the ability of the brain and nervous system in all species to change structurally and functionally as a result of input from the environment. Plasticity occurs on a variety of levels, ranging from cellular changes involved in...
due to their genetic makeups, which affects their ability to adapt to conditions in their environments and effectively learn from experiences. The degree to which intelligence can be linked to genetic heritability
Heritability
The Heritability of a population is the proportion of observable differences between individuals that is due to genetic differences. Factors including genetics, environment and random chance can all contribute to the variation between individuals in their observable characteristics...
increases with age. A study of Dutch twins concludes that intelligence of a 5 year old is 26% heritability, while the intelligence of a 12 year old is 64% based on heritability
Heritability
The Heritability of a population is the proportion of observable differences between individuals that is due to genetic differences. Factors including genetics, environment and random chance can all contribute to the variation between individuals in their observable characteristics...
. Structurally, genetic influences explain 77-88% of the variance in the thickness of the mid-sagittal area
Sagittal plane
Sagittal plane is a vertical plane which passes from front to rear dividing the body into right and left sections.-Variations:Examples include:...
of the corpus callosum
Corpus callosum
The corpus callosum , also known as the colossal commissure, is a wide, flat bundle of neural fibers beneath the cortex in the eutherian brain at the longitudinal fissure. It connects the left and right cerebral hemispheres and facilitates interhemispheric communication...
, the volume of the caudate nucleus
Caudate nucleus
The caudate nucleus is a nucleus located within the basal ganglia of the brains of many animal species. The caudate nucleus is an important part of the brain's learning and memory system.-Anatomy:...
, and the volumes of the parietal
Parietal
Parietal may refer to:*Parietal placentation*Parietal lobe of the brain*Parietal bone of the skull*Parietal scales of a snake lie in the general region of the parietal bone*Parietal cell in the stomach*Parietal pleura...
and temporal
Temporal
Temporal can refer to:* of or relating to time** Temporality in philosophy** Temporal database, a database recording aspects of time varying values** The Temporal power of the Popes of the Roman Catholic Church...
lobes.
Pharmacological influence
Numerous pharmacological developments have been made to help organize neural circuitry for patients with learning disorders. The cholinergicCholinergic
The word choline generally refers to the various quaternary ammonium salts containing the N,N,N-trimethylethanolammonium cation. Found in most animal tissues, choline is a primary component of the neurotransmitter acetylcholine and functions with inositol as a basic constituent of lecithin...
and glutamatergic systems in the brain serve an important role in learning, memory, and the developmental organization of neuronal circuitry. These systems help to capitalize on the critical period and organize synaptic transmission. Autism
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
and other learning disabilities have been targeted with drugs focusing on cholinergic and glutamatergic transmission. These drugs increase the amount of acetylcholine
Acetylcholine
The chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system and central nervous system in many organisms including humans...
present in the brain by increasing the production of acetylcholine precursors, as well as inhibiting acetylcholine degradation by cholinesterases. By focusing on heightening the activity of this system, the brain's responsiveness to activity-dependent plasticity
Activity-dependent plasticity
A defining feature of the brain is its capacity to undergo changes based on activity-dependent functions, also called activity-dependent plasticity. Its ability to remodel itself forms the basis of the brain’s capacity to retain memories, improve motor function, and enhance comprehension and...
is improved. Specifically, glutamatergic drugs may reduce the threshold for LTP
LTP
- Science and technology :* Lunar Transient Phenomena, a short-lived change in appearance of Earth's moon* Long-tailed pair, a differential pair amplifier* Lightweight Telephony Protocol, a signaling protocol...
, promote more normal dendritic spine
Dendritic spine
A dendritic spine is a small membranous protrusion from a neuron's dendrite that typically receives input from a single synapse of an axon. Dendritic spines serve as a storage site for synaptic strength and help transmit electrical signals to the neuron's cell body...
morphology, and retain a greater number of useful synaptic connections. Cholinergic drugs may reconnect the basal forebrain
Basal forebrain
The basal forebrain is a collection of structures located ventrally to the striatum. It is considered to be the major cholinergic output of the central nervous system . It includes a group of structures that lie near the bottom of the front of the brain, including the nucleus basalis, diagonal band...
with the cortex
Cortex
Cortex may refer to:-Sciences:* Cortex , the outer portion of the stem or root of a plant...
and hippocampus
Hippocampus
The hippocampus is a major component of the brains of humans and other vertebrates. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial navigation. Humans and other mammals have two hippocampi, one in...
, connections that are often disrupted in patients with learning disorders.
Psychological factors
Psychological factors and preconceived notions about intelligence can be as influential on intelligence as genetic makeup. Children with early chronic stressChronic stress
Chronic stress is the response to emotional pressure suffered for a prolonged period over which an individual perceives he or she has no control. It involves an endocrine system response in which occurs a release of corticosteroids...
show impaired corticolimbic connectivity in development. Early chronic stress is defined as inconsistent or inadequate care-giving and disruption to early rearing environment. These children showed decreased cognitive function, especially in fluid cognition
Cognition
In science, cognition refers to mental processes. These processes include attention, remembering, producing and understanding language, solving problems, and making decisions. Cognition is studied in various disciplines such as psychology, philosophy, linguistics, and computer science...
, or the ability to effectively utilize working memory
Working memory
Working memory has been defined as the system which actively holds information in the mind to do verbal and nonverbal tasks such as reasoning and comprehension, and to make it available for further information processing...
. The lack of connectivity between the limbic system
Limbic system
The limbic system is a set of brain structures including the hippocampus, amygdala, anterior thalamic nuclei, septum, limbic cortex and fornix, which seemingly support a variety of functions including emotion, behavior, long term memory, and olfaction. The term "limbic" comes from the Latin...
and the prefrontal cortex
Prefrontal cortex
The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.This brain region has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior...
can be blamed for this deficiency.
In addition to stress
Stress (biology)
Stress is a term in psychology and biology, borrowed from physics and engineering and first used in the biological context in the 1930s, which has in more recent decades become commonly used in popular parlance...
, perceptions of intelligence can also play a negative role in cognitive development
Cognitive development
Cognitive development is a field of study in neuroscience and psychology focusing on a child's development in terms of information processing, conceptual resources, perceptual skill, language learning, and other aspects of brain development and cognitive psychology compared to an adult's point of...
. A study at Columbia University
Columbia University
Columbia University in the City of New York is a private, Ivy League university in Manhattan, New York City. Columbia is the oldest institution of higher learning in the state of New York, the fifth oldest in the United States, and one of the country's nine Colonial Colleges founded before the...
showed entity theorists, or people with a belief in fixed intelligence, showed less improvement on cognitive testing after receiving initial feedback than incremental theorists, or people with a belief in malleable intelligence. Entity theorists focus on performance goals and proving their intelligence, which makes them vulnerable to negative feedback
Negative feedback
Negative feedback occurs when the output of a system acts to oppose changes to the input of the system, with the result that the changes are attenuated. If the overall feedback of the system is negative, then the system will tend to be stable.- Overview :...
and failure. This is in contrast to incremental theorists, who focus on learning goals and rebound well from occasional failure or feedback. Incremental theorists focus on challenging tasks to expand intelligence instead of working to prove their own intelligence. Thus, a variety of psychological factors can inhibit one's propensity to expand his intelligence.
Behavioral factors
In the study of malleable intelligence, behavioral factors are often the most intriguing because these are factors humans can seek to control. There are numerous behavioral factors that affect intellectual development and neural plasticity. The key is plasticity, which is caused by experience-driven electrical activation of neurons. This experience-driven activation causes axons to sprout new branches and develop new presynaptic terminalsChemical synapse
Chemical synapses are specialized junctions through which neurons signal to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous system. They are crucial to the biological computations that underlie...
. These new branches often lead to greater mental processing in different areas. For instance, use of the popular Fast ForWord
Fast ForWord
Fast ForWord is a family of educational software products intended to enhance cognitive skills of children, especially focused on developing "phonological awareness" . It is marketed as a therapy for strengthening the skills of memory, attention, processing rate, and sequencing for children...
learning system has been shown to increase visually based IQ. As a result, participants' verbal reading scores also improved. Thus, mental processing generally improved due to an improvement in temporal
Temporal
Temporal can refer to:* of or relating to time** Temporality in philosophy** Temporal database, a database recording aspects of time varying values** The Temporal power of the Popes of the Roman Catholic Church...
processing of the visual field
Visual field
The term visual field is sometimes used as a synonym to field of view, though they do not designate the same thing. The visual field is the "spatial array of visual sensations available to observation in introspectionist psychological experiments", while 'field of view' "refers to the physical...
. Other programs similar to Fast ForWord
Fast ForWord
Fast ForWord is a family of educational software products intended to enhance cognitive skills of children, especially focused on developing "phonological awareness" . It is marketed as a therapy for strengthening the skills of memory, attention, processing rate, and sequencing for children...
have boasted similar results, but recent studies show that the cognitive processing improvements gained from these programs diminish after instruction has ended. In the end, the program intervention may help expedite the neural development of children with less neural plasticity, but after the intervention is removed, children with greater neural plasticity not involved in the program will eventually meet and surpass the program participants.
Taking advantage of the critical period
As previously discussed, the critical periodCritical period
This article is about a critical period in an organism's or person's development. See also America's Critical Period.In general, a critical period is a limited time in which an event can occur, usually to result in some kind of transformation...
is a time of neural pruning and great intellectual development. The time scale for humans to learn language without an accent begins in infancy and ends around 8 years old. Languages learned after 8 years old will be spoken with an accent and will not be processed in the same part of the brain as the native language. Similarly, a study was conducted in which children were exposed to Zulu
Zulu language
Zulu is the language of the Zulu people with about 10 million speakers, the vast majority of whom live in South Africa. Zulu is the most widely spoken home language in South Africa as well as being understood by over 50% of the population...
before the age of 2. The children could discriminate non-native contrasts that adults had difficulty perceiving. Thus, the critical period prepares children to process numerous types of stimulus input that the adult brain cannot process.
Another example of the critical period playing an important role in development is with eyesight and cataracts. Infants born with cataracts will become blind if the surgery to remove the cataract
Cataract
A cataract is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light...
is not done during the critical period
Critical period
This article is about a critical period in an organism's or person's development. See also America's Critical Period.In general, a critical period is a limited time in which an event can occur, usually to result in some kind of transformation...
. After the critical period, the brain map
Brain mapping
Brain mapping is a set of neuroscience techniques predicated on the mapping of quantities or properties onto spatial representations of the brain resulting in maps.- Overview :...
for eyesight will have rewired itself, and the child will be blind. Similarly, rats reared in the dark will maintain the critical period for eyesight until placed in a lit environment, when the vision is corrected. However, the extension of the critical period does not last infinitely. Eventually, without light input, the rats will go blind as their visual cortex is overcome by other neural connections via plasticity.
In regards to cognitive processing, individuals who are considered "genius
Genius
Genius is something or someone embodying exceptional intellectual ability, creativity, or originality, typically to a degree that is associated with the achievement of unprecedented insight....
" often began exploring their fields well before maturity. One obvious example is Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...
, who began studying the universe at age 5 and learned advanced math at age 12. The ability of these geniuses to understand their field is due largely in part to their interest at a young age, during the ongoing critical period. Interestingly, another factor that has a strong correlation with intelligence is breast feeding of infants. Even after normalizing for mother's intelligence, age, education, socio-economic status, and mood fluctuations during pregnancy, breast fed infants show greater scores on cognitive functioning tests, which persisted throughout development.
Executive attention and intelligence
One study conducted by Rosario Rueda and colleagues investigated the effects of an educational intervention in executive attentionAttention
Attention is the cognitive process of paying attention to one aspect of the environment while ignoring others. Attention is one of the most intensely studied topics within psychology and cognitive neuroscience....
in children 4 and 6 years old . Executive attention refers to the self-regulation of cognition
Cognition
In science, cognition refers to mental processes. These processes include attention, remembering, producing and understanding language, solving problems, and making decisions. Cognition is studied in various disciplines such as psychology, philosophy, linguistics, and computer science...
and emotion
Emotion
Emotion is a complex psychophysiological experience of an individual's state of mind as interacting with biochemical and environmental influences. In humans, emotion fundamentally involves "physiological arousal, expressive behaviors, and conscious experience." Emotion is associated with mood,...
. The training focused on developing the child's ability to track moving objects, anticipate events, memorize stimuli over brief periods of time, and inhibit learned responses. This training improved intelligence in the 4-year-old but not the 6-year-old group. The training had no effect on a test of executive attention, the "Attention Network Test".
Environmental factors
Environment plays a significant role in intellectual development, especially the environment present during the critical period. Marion Diamond from the University of California, Berkeley, discovered dendritic spines from infants reared in enriched environments were both longer and more highly branched than dendritic spines in the brains of infants raised in deprived environments. However, a fully enriched environment does not greatly differ from an enriched environment in terms of cognitive development. In other words, multicolored mobiles or Mozart CDs have little consequences on brain wiring. An enriched environment is similar to vitamins, a minimum doseDose
Dose means quantity in the following fields:In nutrition, medicine, and toxicology:* Dose , the quantity of something that may be eaten by or administered to an organism, or that an organism may be exposed to...
is necessary, but taking extra won't help.
Other environmental factors, like disease, play a significant role in intellectual development. A study from Norway by Eriksen et al. concluded that infants born just after the Hong Kong Flu
Hong Kong flu
The Hong Kong flu was a category 2 flu pandemic whose outbreak in 1968 and 1969 killed an estimated one million people worldwide. It was caused by an H3N2 strain of the influenza A virus, descended from H2N2 through antigenic shift, a genetic process in which genes from multiple subtypes reassorted...
pandemic during July–October 1970 scored lower on cognitive tests than others born in 1970 when normalized for parental education, paternal age, and premature percentages. Maternal flu can cause both transient breathing and eating difficulties, both of which have long term effects on the intellectual development of the developing fetus
Fetus
A fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth.In humans, the fetal stage of prenatal development starts at the beginning of the 11th week in gestational age, which is the 9th week after fertilization.-Etymology and spelling variations:The...
.
See also
- Cognitive developmentCognitive developmentCognitive development is a field of study in neuroscience and psychology focusing on a child's development in terms of information processing, conceptual resources, perceptual skill, language learning, and other aspects of brain development and cognitive psychology compared to an adult's point of...
- IntelligenceIntelligenceIntelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....
- Intelligence quotientIntelligence quotientAn intelligence quotient, or IQ, is a score derived from one of several different standardized tests designed to assess intelligence. When modern IQ tests are constructed, the mean score within an age group is set to 100 and the standard deviation to 15...
- NeuroplasticityNeuroplasticityNeuroplasticity is a non-specific neuroscience term referring to the ability of the brain and nervous system in all species to change structurally and functionally as a result of input from the environment. Plasticity occurs on a variety of levels, ranging from cellular changes involved in...
External links
- The Entity Theory of Intelligence - Parenting Science
- Raising Our I.Q. - NY Times