Physiological Psychology: Ch 13 Intelligence and Cognitive Functioning

technology (410)

-diffusion tensor imaging -parieto-frontal integration theory

The imnpairment of sociability in autistic individuals has been linked to:

oxytocin & serotonin

intelligence

the ability to reason, to understand, and to profit from experience.

The structure of intelligence

-Debate whether intelligence is a single capability (lumpers) claim that intelligence is a single unitary capability, which is usually called the general factor or simply g. -Or a collection of several abilities that are more or less independent of each other (splitters) more interested in scores on the subtests of standard IQ tests

autism spectrum disorder

-a set of neurodevelopmental disorders characterized by social deficits, communication difficulties, and repetitive behaviors. i. includes social deficits, communication difficulties and repetitive behaviors ii. Cognitive and Social Impairment 1. Impaired in communication, imagination and socialization 2. Autistics are hypothesized to lack a theory of mind, the ability to infer what other people are thinking based on experience 3. Empathy may come from mirror neurons, which may be deficient in ASD individuals iii. Autistic Savants and High-Functioning ASD individuals 1. An autistic savant is a person with one or more exceptional skills but whose overall functioning is below normal 2. High-functioning individuals with ASD have a limited impairment that can be overcome with effort, like Temple Grandin 3. The source of the skill is unknown but may arise when executive or integrative function within the brain is compromised iv. Brain anomalies 1. Occurs early, during brain development, and includes the brain stem, cerebellum and temporal lobes 2. Lack of coordination between amygdala and ventromedial prefrontal cortex, preventing ASD individuals from looking at faces, as well as tracking objects in space 3. Decreased white matter in adults causes loss of synchronized activity 4. Biochemical anomalies include abnormal serotonin, glutamate, GABA, and oxytocin levels. v. The Environment 1. Disrupted brain development due to high levels of traffic pollution 2. Maternal metabolic conditions such as obesity, diabetes, and hypertension also linked to ASD, though folic acid supplements reduce risks. -siblings of children with autism are 25 times more likely to be diagnosed with autism than other children. -identical twin of a child with autism: 60% -

myelination

-both increases conduction speed and protects against "cross-talk" between neurons -Humans have a greater proportion of white matter (myelinated processes) to gray matter than other animals and IQ varies among individuals with he degree of myelination -Higher in IQ= less brain energy use -lower rate of glucose metabolism -mild intellectual ability (IQs between 50-70: require 20% more neural activity to perform an attention-demanding task than do individuals with IQs of 115 or higher

specific abilities and the brain (410)

-factor analysis: involves giving a group of people several tests that measure cognitive abilities that might be related to intelligence or verbal skills or reaction time -left prefrontal cortex is most active when an individual performs calculations from memory -both come into play during estimation of values i. Linguistic: left frontal and temporal lobes ii. Logical-mathematical: left prefrontal cortex (rote calculation) and parietal cortices (active calculation). iii. Spatial: somatosensory and visual functions with right parietal structures. -Wynn (411) -Rhesus monkeys (411)

___ is the most common childhood-onset behavioral disorder.

ADHD

Down syndrome is caused by maternal alcoholism.

false.

The leading environmental cause of intellectual impairment is

prenatal exposure to alcohol.

Einstein's brain was smaller than the average male's brain, but had higher ratio of glia to neurons in his left parietal lobe.

true.

Some of the loss in intelligence with aging is due to a lack of practice in some of the skills necessary to do well on IQ tests.

true.

brain size

-itself does not determine intelligence -ratio adjusts for the proportion of the brain needed for managing the body and tells us how much is left over for intellectual functions, ratio for humans is one of the highest -11% of the differences among people in intelligence is related to brain size -men have larger brains than women (118 g heavier) -hypotheses: 1. women's brains are more efficient, because of a greater density of neurons and a higher ratio of gray matter to white matter. 2. males superior spatial intelligence requires greater brain capacity -in children with average intelligence, cortical thinking reaches its peak by the age of 8; in children with superior intelligence, thickening continues until age 11 or 12 before thinning to adult levels -general intelligence is correlated with cortical thickening

francis galton

-suggested that higher intelligence depends on greater "mental speed" -IQ scores do in fact correlate with reaction time when IQ test is given without a time limit -IQ score are also correlated with nerve conduction velocity -people who are more intelligent excel on tasks in which stimuli are presented for a short interval and on tasks thats require choices

intelligence quotient (404)

-term associated with the scoring on early intelligence tests designed for use with children. Test was designed to produce a score of 100 for a child performing at the average for his or her chronological age. -score in the form of mental age -Only 2% of the population score above 130 points or below 70 points -first intelligence test was devised by Alfred Binet in 1905 -street smarts: able to perform calculations out in the street that they were unable to perform in a classroom setting. -sternberg argues that intelligence does not exist in the sense we usually conceive of it but is a "cultural invention to account for the fact that some people are able to succeed in their environment better than others"

general factor theorists

406

Which of the following statements regarding brain size is FALSE?

There is no correlation between brain size and intelligence in humans.

with respect to aging and intelligence

a. loss occurs, but it has been overestimated.

the brain and intelligence

i. Einstein had larger parietal lobes, and other researchers suggest that an active, distributed network is present in "intelligent" individuals ii. Brain size (relative to body size) is somewhat correlated to intelligence; other possible correlates are smaller cortical columns and greater frontal gray matter iii. IQ scores are correlated with processing efficiency 1. Higher nerve conduction and processing speed correlated with faster cognitive speed 2. higher myelination increases speed and reduces "cross talk" to adjacent areas 3. reduced energy use 4. greater cortical inter-connectivity -glial cells continue proliferating throughout life. -parietal lobes: involved in mathematical ability and visual- spatial processing -hippocampal (407)

heredity and the environment

i. Heritability of Intelligence 1. About 50% and increases with age; identical twins reared apart are more similar than fraternal twins reared together -41% in childhood, 55% in adolescence, and 66% in adulthood -ASMP: gene that is a major determinant of brain size -PACAP: gene that plays a role in neurogenesis and neural signaling and may have contributed to the formation of human cognitive abilities. -cortical thickness plays role; thinner left cortex= less intelligent on performance tests. ii. The Genetic Controversy 1. Whether ethnic differences in intelligence are genetic. 2. Identical twins raised apart have more similar IQ scores than adopted environments. 3. However, some IQ tests are culturally biased towards certain groups. -height: 90% heritable iii. Environmental effects 1. Level of infectious disease best predictor of national differences in intelligence, as the energy needed to fight off disease decreases brain development. -2 problems: 1. environmental influences are many and, for the most part individually weak. 2. environmental influences are often hopelessly confounded with genetic effects -Adopted children's IQs are more highly correlated with intelligence of their biological parens than with their adoptive parents -infection: IMPORTANT -risk associated pathogens: lower cognitive ability -prenatal exposure to pesticides; 7.0 IQ points lower.

effects of aging on intelligence

i. Perceptual speed dropped after the age of 25, and numeric memory at 60. ii. Default mode network, which encompasses portions of the parietal, frontal and temporal lobes, is responsible for preparedness for action iii. Nonphysical causes such as lack of skill practice, low self esteem, and poor diet can decrease intelligence. iv. Sex hormones can provide protection against the cognitive effects of aging, especially estrogen and testosterone (for spatial memory in men) -alzheimer's disease -reduced activity of numerous genes involved in long-term potentiation and memory storage due to age-related damage -default mode network: portions of the frontal, parietal, and temporal lobes that are active when the brain is at rest or focused internally rather than on the outside world; activity is thought to represent preparedness for action

attention deficit hyperactivity disorder (429)

i. characterized by impulsiveness, inability to sustain attention, learning difficulty and hyperactivity, which persists into adulthood in many cases -develops during childhood and is characterized by impulsiveness, inability to sustain attention, learning difficulty, and hyperactivity -3 types of ADHD combine inattention and hyperactivity-impulsiveness are the most common, but some are predominantly inattentive or predominantly hyperactive-impulsive -antisocial personality disorder, criminal behavior, and drug abuse. -Boys are more than twice as likely to be diagnosed as girls are with rates of 13.2% and 5.6% ii. Neurotransmitter Anomalies in ADHD 1. ADHD is linked to reduced activity in dopamine pathways and impaired reward 2. Ritalin (a stimulant) increases norepinephrine output to the prefrontal cortex and improves impulse control, working memory, and learning -mostly treated with the stimulant drugs methylphenidate and amphetamine. These drugs increase dopamine and norepinephrine activity by blocking reuptake at the synapse -modafinil and atomoxetine: two drugs used to block norepinephrine reuptake, suggest that neurotransmitters rolein ADHD iii. Brain Anomalies in ADHD 1. Multiple areas implicated included prefrontal cortex, cerebellum, and right caudate nucleus of the striatum (reduced in size) 2. ADHD may result from disruption of the attention-inhibition network of the temporal and inferior parietal areas -children with ADHD have reduced volume in the cerebral hemispheres especially the right; in the right caudate nucleus and in parts of the cerebellum iv. Heredity and ADHD 1. ADHD is 5-6 times more prevalent in relatives than non-relatives; concordance is about 79% in identical twins and 32% in fraternal twins. 2. Implicated genes are involved in dopamine, norepinephrine, and serotonin transmission, synaptic functioning, neural development and survival, and learning. 3. 79% for identical twins, 32% for fraternal, 75% across studies 4. ADHD is a complex multi symptom disorder -The gene LPHN3 on chromosome 4 interacts with genes on chromosome 11 to double the risk of ADHD. -LPHN3 affects brain metabolism and predicts how well the patient will respond to stimulant medications, 222 copy number variations in ADHD patients -found in or near genes involved in synaptic transmission, neural development, and learning and other psychological functions ---THE ENVIRONMENT AND ADHD -maternal smoking, stress, abuse of alcohol, stimulants, cocaine, and parental mood and anxiety disorders during pregnancy play a huge role in ADHD in children. -environmental influences include, brain injury, stroke, and pregnancy and birth complications. -LEAD!!! Not good for children -Autism: organophosphate pesticides; children with above average urinary levels of metabolite are twice as likely to be diagnosed with ADHD

intellectual disability

i. intellectual disability: IQ of less than 70 and inability to live independently. ii. Down syndrome, caused by having three chromosome 21's, results in IQ values in the 40-55 range and occurs in 1 of every 700 births. iii. Fragile X syndrome due to mutation in fragile X mental retardation 1 gene (FMR1), where CGG nucleotide repeats exceed 45. iv. Phenylketonuria (PKU) is due to an inherited inability to metabolize phenylalanine v. Hydrocephalus is due to cerebrospinal fluid buildup in the ventricles