Midterm 1

Hindsight bias

The tendency to believe, after learning an outcome, that we could have predicted it

Overconfidence

People tend to think they know more than they do (usually happens in academic and social behavior)

Perception of order in random events

People perceive patterns to make sense of the world (often in random and unrelated data ppl find order b/c random sequences often don’t look random)

The scientific method

A process of testing ideas about the world by

* setting up situations that test our ideas
* making careful organized observations
* analyzing whether data fit w our ideas
* accept conflicting data as a means to improve theory

Sci. Method steps

1. ask a question
2. make prediction
3. gather data
4. analyze data
5. draw conclusions

Descriptive research

Systematic, **objective** observation of people

* goal: provide a clear, accurate picture of ppl’s **behaviors**, **thoughts**, and **attributes**

What are 3 forms of descriptive research?

Case studies

* Examines 1 individual in depth
* Cannot be used to generalize

Naturalistic observations

* Records behavior in natural development
* Describes but doesn’t explain behavior
* Can be revealing

Surveys & interviews

* Examines many cases in less depth
* Utilizes random sampling of pop. for best results

Correlation

A measure of how closely 2 factors vary together or how well you can predict a change in one from observing a change in the order

Correlation coefficient

* a number between -1 & 1
* provides a statistical measure of how closely 2 things vary together & how well one predicts the other

Postive correlation

* 0 - 1
* Indicates a **direct relationship**, meaning that 2 things increase together or decrease together

Negative correlation

* -1 - 0
* Indicates an inverse relationship: as one think increases, the other decreases

Correlation and Causation

No matter how strong the relationship, **CORRELATION DOESN’T PROVE CAUSATION**

Experimentation

Researchers can focus on the possible effects of one or more factors in several ways :

* manipulating independent variables
* holding constant other factors

Double blind experiment

* neither those in the study nor those collecting data know which group is receiving treatment
* treatment’s actual effects can be separated from potential placebo effect
* eliminates bias

Placebo effect

Results caused by expectations alone

Mode

most frequently occurring scores in a distribution

Mean

Average

Median

Middle score in a distribution

Range

Difference between highest & lowest scores

Standard deviation

measure of how much scores vary around the mean score distribution

Generalizations

When made on a few unrepresentative cases are **unreliable**

Biological framework perspective

Everything psychological is biological

Brain v. mind

brain is the **organ** that enables the mind

Phrenology

belief that as your brain grows it pushes on your skill and bumps are created

Soups v. sparks

Debate over the chemical vs electrical conduction of the nerve impulses at the synapse

Neuron

whole cell

Synapse

Where neurons meet and communicate

Axon

passes messages away from the cell body to other neurons

Dendrite

receives message

Myelination

Layers of myelin that wrap around the neuronal axons. and acts as layer of insulation for the transmission of electric action potentials down the neuronal axon

* helps speed up neural impulses

Schwann cells

surround neurons, keeping them alive and sometimes covering them with a myelin sheath

What is the function of neurotransmitter dopamine ?

Influences movement, learning, attention, & emotion

What is the function of serotonin?

Affects mood, hunger, sleep, and arousal

What parts of the body does the **Central Nervous System** include?

Brain, brainstem, and spinal cord

What is the function of the central nervous system?

* It’s the body’s processing centre
* Body’s decision maker

Peripheral nervous system

Sensory & motor neurons connecting the CNS to the rest of the body for gathering and transmitting information

What 2 systems Peripheral Nervous System

Includes autonomic and somatic

What does the somatic system do?

* Sensory input
* Motor output; controls skeletal muscles
* **Motor control**

What does the autonomic system control?

Controls self regulated action of internal organs and glands

* **unconscious control**
* temperature, hear rate, digestion, breathing

What 2 systems does the autonomic system include?

Sympathetic and parasympathetic

What does the sympathetic system do?

Arouse

Sympathetic nervous system

Arouses and expands energy and enables voluntary control of skeletal muscles

* controls FIGHT v FLIGHT

What does the parasympathetic system do?

Calm

Parasympathetic

calms and conserves energy, allowing routine maintenance activity and controls involuntary muscles and glands

* kicks in when threat subsides

Nervous system

The body’s speedy, electrochemical communication network, consisting of all the nerve cells of the central and peripheral nervous systems

Efferent

Signals from brain down to rest of the body (peripheral sys.)

Afferent

Signals from rest of body up to brain

What are the 3 types of neurons?

Sensory, motor, interneurons

Sensory neurons

Bring sensory info

Motor neurons

carry instructions away from the brain

Interneurons (within brain and spinal cord)

Communicative with one another and process infor between the sensory input and motor output

* serve as short cuts

Reflex pathway

Hand withdrawal reflex

* information is carried from skin receptors along a sensory neuron to the spinal cord
* from there it is passed via **interneurons** to motor neurons that lead to the muscles in the hand and arm
* B/c this this reflex involves only the spinal cord, the hand jerks away from the candle flame even before information about the event has reached the brain, causing the experience of pain

Endocrine system

Glands that secrete hormones into the blood stream

Pituitary gland

* master gland
* influences hormone release by other glands, including adrenal glands, thyroid, & pancreas

What is the relationship between the pituitary gland and the hypothalamus?

The hypothalamus influences pituitary gland which influences other glands which release hormones and influence brain

EEG

* electroencephalogram
* picks up electrical signals
* not very accurate at knowing what cell was active
* good at figuring out WHEN it was fired

PET

* position emission tomography
* better spacial resolution
* radioactive ion of iodine & glucose
* injected into body
* iodine stays in cell and releases a glow
* it it lights up more then a lot of glucose is being taken up

MRI

* magnetic resonance imaging
* photograph

fMRI

* functional MRI
* breaks the brain down
* if one area is significantly more active than the others it lights up

DTI

* diffusion tensor imaging
* gray matter has no myelin
* shows diff stages of myelination

What are the parts of the brainstem?

medulla and pons

Medula

located at base of the brainstem; controls heartbeat and breathing

Pons

* Sits above the medula
* Helps coordinate movement

Reticular formation

passes through each structure (reaches into thalamus)

* associated with activity & responsivity levels
* if you cut the RF you enter a coma
* stimulate RF = wide awake

Thalamus

serves as a hub for lots of varied info

Cerebellum

* Aids in judgement of time, sound, & texture discrimination, balance, and emotional control
* Coordinates voluntary movement & life-sustaining functions
* Helps process & store information outside of awareness
* “little brain behind the brain”
* helps maintain muscle memory, texture differentiation

The Limbic System

* Neural system that sits between brain’s older part and its cerebral hemisphere
* neural centers include:
* hippocampus
* amygdala
* hypothalamus

Hippocampus

Explicit **memory** encoding/retrieval

Amygdala

2 small clusters of neurons, associated with **emotional activity**

Hypothalamus

Internal maintenance, measures levels of hunger, thirst, sexual arousal, emotion, reward, controls pituitary gland (master gland)

Cerebral cortex

* outermost layer of brain,
* thin as a stamp
* covers all 4 lobes of the brain

What are the 4 lobes of the brain?

* Frontal lobe
* Parietal lobe
* Occipital lobe
* Temporal lobe

Frontal lobe

associated with:

* speaking
* judgement
* planning
* decision making

Parietal lobe

* Upper back sections of brain


* processes some sensory input (touch) and body position

Occipital lobe

* lower back section of brain


* receive & process visual info

Temporal lobe

* located behind temples


* process audio info

Motor cortex

* located at rear of frontal lobes
* Mouth occupied most of cortical space requiring aid of motor cortex
* @@**Stimulating motor cortex can cause body part movement**@@

What are the 3 cortexes that make up the sensory cortex?

* Visual cortex
* Auditory cortex
* Somatosensory cortex

Somatosensory cortex

Process information from skin senses and body parts movement

Phineas Gage

* Pole went through skill
* It destroyed significant section of Gage’s brain
* Story: He had major personality changes
* Used to be sweet & nice, turned mean & unpredictable
* Reality: very minor change reported by those close to him

Brain’s plasticity

If one hemisphere is damaged early in life, other will assume many functions by reorganizing or building new pathways

* **Plasticity diminishes later in life** (but it is capable of remarkable rewiring)
* Brain sometimes mends itself by forming new neurons through neurogenesis

Corpus Callosum

large band of neural fibers connects the 2 brain hemispheres

What happens if the corpus callosum is severed?

* Info sharing doesn’t take place


* info is processed independently in each hemisphere

Left hemisphere

Good at making quick, exact interpretations of language

Right hemisphere

Excels in making inferences, modulating speech and facilitating self awareness

What does it mean right handed?

* \~90% of ppl are **right handed** & process speech primarily in **left hemisphere**

What does it mean to be left handed?

* More likely to have reading disabilities, allergies, & migraines
* Also more common among musicians, mathematicians, athletes, & artists

Barrel cortex

Structure that is used extensively as a tool to study sensory processing & development

Lateralization

The left and right sides of the brain are specialized to attend to different information, to process sensory inputs in different ways and to control different types of motor behavior

* aka hemispheric specialization

Contralateral processing

When a stimulus is processed on the opposite side to where it was detected.

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Give an example of contralateral processing

Information from the right half of the visual field is detected by the left half of the retina in both eyes and is processed by the left hemisphere

Remote control rat

* rat has an electrode implanted in a reward center of its hypothalamus
* it will cross an electrical grid, accepting painful shocks in order to press a lever that sends impulses to its hypothalamus (reward center)

Sensation

bottom down process by which the **physical sensory system** **receives** and **represents** **stimuli** at the **very basic level of sensory receptor & works up**

Perception

Top down mental process of organizing and interpreting sensory input from experience and expectations

Transduction

conversion of one form of energy into another

Weber’s law

Minimum difference a person can detect between any 2 stimuli half the time; increases with stimulus difference

Subliminal stimuli

Stimuli that are too weak to detect 50% of the time

Perceptual set

Mental tendencies and assumptions that affect (top-down) what we hear, taste, feel, and see

What determines our perceptual set?

Assumptions

* Schema’s organize & interpret unfamiliar information through experiences
* Pre-existing schemas influence (top-down) processing of ambiguous sensation, interpretation, including gender stereotypes

How do we see light?

We see light as only a thin slice of the broad spectrum of electromagnetic energy

* the portion visible to humans extends from the blue violet to the red light wavelengths
* After entering the eye and being focused by a lens, light energy particles strike the eye’s inner surface, ^^**the retina**^^