Early developmentEarly development

Depiction of the Fetus at 10 Depiction of the Fetus at 10 weeksweeks

Gender typically Gender typically determined by sonogram at determined by sonogram at 20 weeks (not always 20 weeks (not always accurate)accurate)

Gender test can be done Gender test can be done sooner and more accurately sooner and more accurately by extracting amniotic fluid by extracting amniotic fluid from the placentafrom the placenta

Development of humansDevelopment of humans

ZygoteZygote – conception – 2 weeks: genetic structure is formed – conception – 2 weeks: genetic structure is formed EmbryoEmbryo – 2 to 8 weeks: All of the organs are formed and will begin to – 2 to 8 weeks: All of the organs are formed and will begin to

function shortly; limbs have also begun to formfunction shortly; limbs have also begun to form FetusFetus – 9 weeks to birth – 9 weeks to birth

– Prior to the 11Prior to the 11thth week, a yoke sac provides blood cells for the fetus. week, a yoke sac provides blood cells for the fetus. After the 11After the 11thth week, the fetus’ own liver, spleen, and bone marrow week, the fetus’ own liver, spleen, and bone marrow take over blood production. take over blood production.

– Umbilical cord provides food and oxygen & removes wasteUmbilical cord provides food and oxygen & removes waste– Thumb sucking may occur if the limb floats around the mouthThumb sucking may occur if the limb floats around the mouth– Toxic agents at different developmental periods will result in Toxic agents at different developmental periods will result in

different types of damage (e.g., late = limbs vs. early = organs)different types of damage (e.g., late = limbs vs. early = organs)

Early abilities of the infantEarly abilities of the infant

Reflexes (rooting, sucking, Reflexes (rooting, sucking, babinski or palmer, babinski or palmer, stepping, orienting, gag, stepping, orienting, gag, etc.)etc.)

Can recognize mother’s Can recognize mother’s voice within 2 daysvoice within 2 days

Initially the visual system is Initially the visual system is only accurate up to 6 only accurate up to 6 inches (distance from inches (distance from baby’s face to mother’s baby’s face to mother’s when breast feeding). when breast feeding).

Important environmental factorsImportant environmental factors

Physical contact – Physical contact – warmth, contactwarmth, contact, & feeding, & feeding– Harlow’s (1958) monkeys & choice of mothersHarlow’s (1958) monkeys & choice of mothers

Familiarity – strong attraction to facial features that were Familiarity – strong attraction to facial features that were ingrained during critical periodsingrained during critical periods– Lorenz (1952) demonstrated the importance of Lorenz (1952) demonstrated the importance of

imprinting in ducksimprinting in ducks– Humans show periods of Humans show periods of sensitivitysensitivity rather than rather than

criticalcritical periods periods Deprivation typically results in aggression, and asocial Deprivation typically results in aggression, and asocial

behaviorbehavior

Early parental learningEarly parental learning

Attachment styles in animals Attachment styles in animals (Bowlby) and in humans (Bowlby) and in humans (Ainesworth)(Ainesworth)– Secure, avoidant, anxious-Secure, avoidant, anxious-

ambivalent (disorganized)ambivalent (disorganized) Parenting styles – although Parenting styles – although

there are innate differences there are innate differences between children, the child’s between children, the child’s environment (which includes environment (which includes parenting) can also alter parenting) can also alter outcomesoutcomes– authoritarian, permissive, authoritarian, permissive,

authoritative authoritative

Theoretical stages of developmentTheoretical stages of development

Piaget (1969, 1972) Piaget (1969, 1972) – Sensorimotor, 12-18 months: reflexes, movementSensorimotor, 12-18 months: reflexes, movement– Preoperational, 2-7 yrs: internal mental Preoperational, 2-7 yrs: internal mental

representations (object permanence), egocentricrepresentations (object permanence), egocentric– Concrete operations, 7-12 yrs: conservation of mass, Concrete operations, 7-12 yrs: conservation of mass,

reversible processes, etc.reversible processes, etc.– Formal Operations, 12 yrs - : abstract thinking, Formal Operations, 12 yrs - : abstract thinking,

second order relationssecond order relations Vygotsky (1934) – zone of proximal development: Vygotsky (1934) – zone of proximal development:

difference between observable abilities and potential difference between observable abilities and potential (given the right context)(given the right context)

Research to study developmentResearch to study development

Symbolic representation (vs. “the shrinking Symbolic representation (vs. “the shrinking or enlarging machine”) – Judy DeLoacheor enlarging machine”) – Judy DeLoache

Language acquisition (sounds, vocal chord Language acquisition (sounds, vocal chord training follows understanding, use of sign training follows understanding, use of sign language is more advanced)language is more advanced)

Object permanence may develop much Object permanence may develop much earlier (gazing times for impossible events) earlier (gazing times for impossible events)

Kagen: temperament (Neuroticism & Extraversion) Kagen: temperament (Neuroticism & Extraversion)

Erikson’s Developmental Stages (lifespan model)Erikson’s Developmental Stages (lifespan model)

1. Trust vs. mistrust1. Trust vs. mistrust

- infant learns to trust - infant learns to trust parents for survival parents for survival needsneeds

4. Industry vs. 4. Industry vs. InferiorityInferiority

- trial and error with - trial and error with mastery, learn which mastery, learn which tasks you can do.tasks you can do.

7. Generativity vs. 7. Generativity vs. stagnationstagnation

- Have you achieved - Have you achieved anything productive?anything productive?

2 Autonomy vs shame2 Autonomy vs shame

- learn to act - learn to act independent of independent of parentsparents

5. Identity vs. Role 5. Identity vs. Role confusionconfusion

- self identity begins to - self identity begins to form (why now?)form (why now?)

8. Integrity vs. despair8. Integrity vs. despair

- Happiness with - Happiness with one’s life, though one’s life, though resigned to the fact it’s resigned to the fact it’s endingending

3. Initiative vs. guilt3. Initiative vs. guilt

- learn to initiate - learn to initiate actions, thoughts, and actions, thoughts, and emotional emotional experiencesexperiences

6.Intimacy vs isolation6.Intimacy vs isolation-adult relationshipsadult relationships- “ “decision” is often decision” is often made more than oncemade more than once

Erikson’s lifespan developmentErikson’s lifespan development

Most development occurs early in life (5 of 8 Most development occurs early in life (5 of 8 stages by adolescence)stages by adolescence)

A series of conflicts which must be resolved A series of conflicts which must be resolved by achieving a balanceby achieving a balance

Stage theory implies that early problems Stage theory implies that early problems negotiating stages leads to later problemsnegotiating stages leads to later problems

Most research suggests that the Most research suggests that the developmental nature of the stages is developmental nature of the stages is largely determined sociallylargely determined socially

Moral DevelopmentMoral Development

1. Preconventional 1. Preconventional – Don’t get caughtDon’t get caught– What’s in it for meWhat’s in it for me

2. Conventional 2. Conventional – I am good/niceI am good/nice– Preserve social orderPreserve social order

3. Postconventional3. Postconventional– Ensuring the rights of allEnsuring the rights of all– What is best for everyoneWhat is best for everyone

Theoretical dilemmas vs. realityTheoretical dilemmas vs. reality Men vs. womenMen vs. women

Sensation and PerceptionSensation and Perception

Information from the environment is transferred to our brain Information from the environment is transferred to our brain by way of a series of neurochemical messages.by way of a series of neurochemical messages.

Primed to detect changes in the environment (i.e., to notice Primed to detect changes in the environment (i.e., to notice differences); detection = when neurons “fire”differences); detection = when neurons “fire”

Absolute thresholdAbsolute threshold – amount of a stimulus needed to – amount of a stimulus needed to detect it 50% of the time.detect it 50% of the time.

JNDs (just noticeable differences)JNDs (just noticeable differences)

Difference threshold (JNDDifference threshold (JND) – the amount of change in a ) – the amount of change in a stimulus necessary to detect that change 50% of the timestimulus necessary to detect that change 50% of the time

The JND can be calculated as a constant proportion of the The JND can be calculated as a constant proportion of the original stimulus (Weber’s Law) original stimulus (Weber’s Law) – e.g., electric shock (.01), heaviness (.02), loudness e.g., electric shock (.01), heaviness (.02), loudness

(.05), brightness (.08), salty taste (.20)(.05), brightness (.08), salty taste (.20)

The firing and resting of neuronsThe firing and resting of neurons

Sensory adaptation – neurons become fatigued from constant Sensory adaptation – neurons become fatigued from constant firing, so this process slows down. This results in decreased firing, so this process slows down. This results in decreased sensitivity for unchanging stimulisensitivity for unchanging stimuli– Why do the receptors in our eyes not grow fatigued from Why do the receptors in our eyes not grow fatigued from

unchanging stimuli? (less sensitivity = not seeing them)unchanging stimuli? (less sensitivity = not seeing them)– Eyes are constantly quivering so that the same Eyes are constantly quivering so that the same

information does not appear on the same photoreceptors. information does not appear on the same photoreceptors. When eyes are held steady, objects disappearWhen eyes are held steady, objects disappear

VisionVision

Receptors in the eyesReceptors in the eyes Human visual receptors are sensitive to Human visual receptors are sensitive to

wavelengths from 400-700 nanometers, which is a wavelengths from 400-700 nanometers, which is a small portion of the electromagnetic spectrumsmall portion of the electromagnetic spectrum

Rods – primarily used to detect lightRods – primarily used to detect light– located largely in the periphery of the retinalocated largely in the periphery of the retina– app. 120 million, but only one typeapp. 120 million, but only one type– abundant in all vertebrates. abundant in all vertebrates.

Cones – Primarily used to detect color and detailCones – Primarily used to detect color and detail– More concentrated in the foveaMore concentrated in the fovea– 7-8 million, and 3 types7-8 million, and 3 types– adapt faster to changes in lightadapt faster to changes in light– abundant in species active in the dayabundant in species active in the day

About 1/50 are color blind (more males) and most common type is red-green color blindness

Ambiguous ImagesAmbiguous Images

= =

Necker CubeNecker Cube

Context effectsContext effects

The brain uses information surrounding any stimulus to The brain uses information surrounding any stimulus to define the stimulus as well as general (Gestalt) principles define the stimulus as well as general (Gestalt) principles of similarity, continuity, closure, and proximity. of similarity, continuity, closure, and proximity. – Sometimes the surrounding info can result in erroneous Sometimes the surrounding info can result in erroneous

conclusions by the brain (e.g., the blind spot example; conclusions by the brain (e.g., the blind spot example; figure-ground comparisons, the Muller-Lyer illusion, the figure-ground comparisons, the Muller-Lyer illusion, the size of the sun on the horizon, contrast effects, etc.)size of the sun on the horizon, contrast effects, etc.)

– Information can also be neglected or obscured due to Information can also be neglected or obscured due to 1) 1) The object, 2) the surrounding information, 3) The object, 2) the surrounding information, 3) expectations, and 4) attention. expectations, and 4) attention.

http://people.uncw.edu/cohend/teach/cinema/INDEX.HTM

Occipital lobes primarily for visionOccipital lobes primarily for vision

Context and Top Down ProcessingContext and Top Down Processing

Aoccdrnig to a rscheearch at Cmabrigde Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn’t mttaer in waht oredr Uinervtisy, it deosn’t mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit porbelm. Tihs is you can sitll raed it wouthit porbelm. Tihs is bcuseae the huamn mnid deos not raed bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a ervey lteter by istlef, but the wrod as a wlohe.wlohe.

Color vision theories

Trichromatic theory – there are three types of cones (responding to three primary colors varying in wavelengths)

Opponent process theory – a single neuron is responsible for the detection of two colors, one while firing and one while inhibited

Red-green, blue-yellow, black-white Explains after image effects and color blindness;

explains the 4 primary colors Retinex theory – We perceive color through the cerebral

cortex’s comparison of various retinal patterns (i.e., color is a construction of the brain, not a property of the light itself.

All three theories provide some important details of color vision.

Cues for visual distanceCues for visual distance

Binocular cues Binocular cues – 1) convergence (muscular)1) convergence (muscular)– 2) retinal disparity2) retinal disparity

How can you convey distance on a two-dimensional How can you convey distance on a two-dimensional plain?plain?

Monocular cuesMonocular cues– Relative size, relative height, relative brightness, Relative size, relative height, relative brightness,

overlap, texture (smooth from greater distance), linear overlap, texture (smooth from greater distance), linear perspective, relative motion (fixation point: beyond it perspective, relative motion (fixation point: beyond it objects move with us, vs. before it)objects move with us, vs. before it)

HearingHearing

Two theories on how it worksTwo theories on how it works– 1) 1) place theoryplace theory – we hear different pitches because – we hear different pitches because

sound waves of different frequencies trigger receptors at sound waves of different frequencies trigger receptors at different points along the membrane (high pitch sounds different points along the membrane (high pitch sounds occur at the beginning of the membrane near the occur at the beginning of the membrane near the cochlea) – the guitar string analogycochlea) – the guitar string analogy

HearingHearing 2) 2) frequency theoryfrequency theory – membrane vibrates (neurons fire) – membrane vibrates (neurons fire)

with the same frequency as the incoming sound waveswith the same frequency as the incoming sound waves Problem is that a neuron can only fire 1000/sec and we Problem is that a neuron can only fire 1000/sec and we

hear sound waves beyond such frequencieshear sound waves beyond such frequencies Solution: the Solution: the volley principlevolley principle – neural cells fire – neural cells fire

alternatively in order to reach the higher frequencies alternatively in order to reach the higher frequencies (e.g., 2 cells can reach 2000/sec) (e.g., 2 cells can reach 2000/sec)

– Sound intensity: range from 0 dB (lowest sound audible to Sound intensity: range from 0 dB (lowest sound audible to humans) to 180 dB (rocket launch pad; hearing loss is humans) to 180 dB (rocket launch pad; hearing loss is inevitable – front speakers at rock concert = 120dB)inevitable – front speakers at rock concert = 120dB)

– Loudness (dB = 1/10Loudness (dB = 1/10thth of bell), Pitch (frequency in Hertz), of bell), Pitch (frequency in Hertz), & Timbre (complexity; 1 sound wave or many)& Timbre (complexity; 1 sound wave or many)

EcholocationEcholocation – use of sound to locate source of sound – use of sound to locate source of sound Equilibrium Equilibrium – fluid in the vestibular sacs of the inner ear for – fluid in the vestibular sacs of the inner ear for

balancebalance

Sense of smellSense of smell

Olfactory functioning – a more developed sense in other Olfactory functioning – a more developed sense in other species (e.g., larger portion of the dog brain is devoted to species (e.g., larger portion of the dog brain is devoted to smell; they experience the world in this way, olfactory smell; they experience the world in this way, olfactory memories, dream?)memories, dream?)– Memories based on smell have very long durationMemories based on smell have very long duration– Pheromones secreted by animals to trigger reactions Pheromones secreted by animals to trigger reactions

(identification, territory, sexual availability, etc.)(identification, territory, sexual availability, etc.)– Female have more discriminating sense of smellFemale have more discriminating sense of smell– Can ID women from smell of sweat (at 1.5 inches)Can ID women from smell of sweat (at 1.5 inches)– Can be damaged from infection, disease, smoking (2 Can be damaged from infection, disease, smoking (2

packs/day for 10 years will need 10 more years of packs/day for 10 years will need 10 more years of abstinence for sense of smell to return to normal) abstinence for sense of smell to return to normal)

Sense of tasteSense of taste

Taste – four basic tastes of sour (sides), bitter Taste – four basic tastes of sour (sides), bitter (back), salty (sides), & sweet (tip). (Umami – taste (back), salty (sides), & sweet (tip). (Umami – taste for glutamates:MSG)for glutamates:MSG)– Locations are just concentrations of sensitivityLocations are just concentrations of sensitivity– Saliva spreads tastes to all parts of the tongueSaliva spreads tastes to all parts of the tongue– Olfactory sense enhances taste (apple & potato taste Olfactory sense enhances taste (apple & potato taste

the same without smell; only 5% correctly identified the same without smell; only 5% correctly identified garlic, chocolate, and coffee without smell)garlic, chocolate, and coffee without smell)

– Attractiveness of food is influenced by color, temp, and Attractiveness of food is influenced by color, temp, and texture, along with social/cultural experiences (a bowl texture, along with social/cultural experiences (a bowl of worms?)of worms?)

Senses - continuedSenses - continued

Kinesthesia – skeletal receptors in the muscles & Kinesthesia – skeletal receptors in the muscles & joints that inform brain of position of limbsjoints that inform brain of position of limbs

Synesthesia – A neurological disorder involving a Synesthesia – A neurological disorder involving a mingling of the senses (sensory info is interpreted mingling of the senses (sensory info is interpreted by the wrong sense). Taste how a shape feels? by the wrong sense). Taste how a shape feels?

Adaptive sensesAdaptive senses

Adaptation of the brain is evidenced when Adaptation of the brain is evidenced when sensory information is altered to facilitate sensory information is altered to facilitate functioning (how long does it take the brain functioning (how long does it take the brain to adapt?)to adapt?)– Glasses that invert the visual field (QB from Glasses that invert the visual field (QB from

Stanford)Stanford)– MadonnaMadonna

Maladaptive sensesMaladaptive senses

Extra-sensory perception! – knowledge of the Extra-sensory perception! – knowledge of the world without using the usual sensory channelsworld without using the usual sensory channels– Most evidence is anecdotal which is not accurate (e.g., Most evidence is anecdotal which is not accurate (e.g.,

forget premonitions that don’t occur)forget premonitions that don’t occur)– Studies in parapsychology focus on ESP with the Studies in parapsychology focus on ESP with the

general conclusion that there is no effectgeneral conclusion that there is no effect– Secrets of the psychics Secrets of the psychics

Recall that we can perceive without knowing it Recall that we can perceive without knowing it (subliminal perception), but this is not ESP(subliminal perception), but this is not ESP

Exam ReviewExam Review

Questions for next week’s exam? (Bring Questions for next week’s exam? (Bring narrow scantron and #2 pencil)narrow scantron and #2 pencil)

Review sections to be coveredReview sections to be covered Please sign-up for experiments ASAPPlease sign-up for experiments ASAP Following the break in the spring semester: Following the break in the spring semester:

The brain and CNS & how neurotransmitters The brain and CNS & how neurotransmitters work. work.