Transcript The philosophical position that every behavior has a cause is known

Neurons: How the brain communicates
 Neurons – billions used to convey info.
Throughout the body
 Dendrites – take in neurochemical info
 Axon – sends messages to next neuron
– Sends message faster if mylenated
 Damage can occur from injury or disease
– Most common for young adults?
Brain injuries
 1) Trauma (stable or recovery course)
– Damage at point of trauma, opposite side, and sides
due to axonal shearing)
 2) Disease (progressive course)
– Location may be localized, and localization defines
different diseases and pathologies
 Brain damage can be predicted by 1) duration of
unconsciousness, and/or 2) duration of amnesia,
and/or 3) location and extent of damage
Communication
 Neuronal impulse (electrical within &
chemical between neurons)
 Neurochemicals are also referred to as
neurotransmitters
– e.g., acetylcholine assists in motor functions,
serotonin assists with mood and sleep,
dopamine plays role in movement, emotional
control, alertness, etc.
Divisions of the nervous system
 The nervous system monitors/controls almost
every organ system through a series of positive
and negative feedback loops.
 CNS - brain & spinal cord.
 Peripheral NS (PNS) connects the CNS to other
parts of the body, and is composed of nerves
(bundles of sensory and motor neurons).
– Voluntary muscles and sensory info and involuntary
muscles -autonomic nervous system
 Sympathetic (expends energy) and parasympathetic (conserves
energy)
Divisions of the brain
 The lobes: 1. Frontal (higher cognitive &
motor functioning), 2.Occipital (visual
processing), 3. Temporal (auditory
processing), & 4. Parietal (sensations of the
skin and muscles)
 Right hemisphere
– visual-spatial processing
 Left hemisphere
– language production (Brocha’s area)
– comprehension (Wernicke’s area)
How the brain works
 Corpus callosum – connects the two hemispheres
of the brain and allows them to communicate
– Severed (surgically) in some patients with severe
forms of epilepsy to prevent grand mal seizures
from spreading to both hemispheres
 Roger Sperry’s work on split brain patients
– Each hemisphere has unique functions and can
be autonomous
– Hemispheric isolation creates potential for errors
 Migration of functioning – transfer of functioning
that can occur when part of the brain is damaged
(more likely if patient is young)
Neurons in Hippocampus
MCI
Dementia
Latency
Optimal
Aging
Neurocognitive Fitness
Induction
15
10
5
Years Prior to
Dementia Diagnosis
0
Trends in MCI and Alzheimer’s
Number of People Diagnosed
(in millions)
70
60
Alzheimer's
MCI
50
40
30
20
10
0
2000
2010
2020
2030
2040
2050
Year
Unvergatz et al, 2001
Prevalence
Annual % Conversion to AD
MCI
AD
Neither
Converters to AD
Non-converters
Six-Year % Conversion
Converters to AD
Non-converters
Neuronal Stem Cells
Conditioning in everyday life
 Cancer patients receiving trials of chemotherapy
show a weakening of their immune system when
exposed to the hospital room where they received
chemotherapy
– Can we condition increases in immune system?
 Placebo effects with drugs – If a pill has worked for
you before a similar pill (even an inert substance)
can not only cure a headache, but actually result
in neurochemical changes in your body
 Behavioral change: A Clockwork orange,
reconditioning prisoners, buzzer pants, etc.
 Salivating to the golden arches, etc.
Conditioning dogs and rats
 Watson & Raynor (1920) trained a young infant
(Little Albert) so that he would e afraid of a rat.
 Before conditioning
– Present white rat – no fear (neutral stimulus)
– Loud noise – fear (unconditioned response)
 Conditioning
– Pair the white rat (neutral stimulus) with the loud
noise (unconditioned stimulus)
 After conditioning
– White rat = fear (conditioned response)
– The white rat is now a conditioned stimulus
Key concepts
 What happens if we keep exposing Albert to the
rat with no loud sound? Eventually…
 Extinction - CS no longer produces the CR
 Spontaneous recovery - after a break, the
previously extinct CS produces the CR
 Higher order conditioning - a CS is paired with
another CS to get the CR
 What happens if we use something similar to a
white rat? (a lesson from alcohol poisoning)
Key concepts - continued
 Generalization - producing the same CR for a
similar CS (e.g., anything like a white rat)
 Discrimination - produces a CR for only a very
specific CS (e.g. only the specific white rat)
 One time conditioning (Garcia effect) - learning
occurs after a single pairing (e.g., sheep and
wolves)
– Why would this be adaptive for aversive CRs?
– This can occur even for reinforcers and lead to
non-productive behavior (e.g., superstitious
behavior)
Operant conditioning
 To explain most of your day-to-day behavior (nonreflexive actions no required temporal association)
 Law of effect – every behavior has a
consequence, and the consequence determines if
the behavior will re-occur (temporal association is
no longer required)
 Reinforcement - anything that increase the
incidence of the behavior to which it is linked
 Punishment - anything that decreases the
incidence of the behavior to which it is linked
Possible examples of reinforcers and
punishers
Reinforcer
Positive
To give praise, love,
attention, money,
etc.
To remove an
aversive stimulus
Negative like pain, noise, etc.
Punisher
To give a shock, a
spanking, a fine, etc.
To remove
something valued
like freedom,
attention, etc.
Delivery (Schedules) of reinforcement &
punishment
 Continuous - best way to acquire a new behavior
(or extinguish an existing behavior)
– Why not ideal to maintain the new learning?
 Ratio - number of responses for the reinforcement
 Interval – there is an interval of time before the
next response is reinforced/punished
 Variable - changing schedule
 Fixed - stable schedule
Other schedules
Fixed
Interval
Ratio
Variable
Pay checks, boss
who “checks in” at
9am and 4pm, etc.
- lengthy breaks until
interval approaches
(bursts of activity)
Real estate agent,
busy phone line, etc.
- slow but steady
rate (busy phone)
Assembly line
worker
- decrease in work
after reinforced
Slot machines
- very productive
schedule with
minimal pausing
Behavioral Applications
Treatment of OCD & Simple phobias – Phobias are intense
fears (or non-normative fears) that lead to dysfunction
– Systematic desensitization – developed by J. Wolpe
 Establish a fear hierarchy – from least feared to most
feared
 Systematically expose the individual to each stimulus
on the fear hierarchy beginning with the lowest (up to
several months)
 Must be in a relaxed state while exposed to the
stimulus
 Must NOT remove the feared stimulus until fear is
diminished otherwise the fear is reinforced
 For OCD – have obsession with response prevention
Personality: A stable pattern of
behaviors, cognitions, and affect
What determined your personality? (explanation)
Some examples..
 Internal and unknown conflicts?
– Freud and the psychodynamic movement (ID, Ego,
Superego)
– Defense mechanisms of denial, intellectualization,
displacement, sublimation, projection, and reaction
formation
– Research by Adams, Wright & Lore, 1986 on arousal in
homophobic and non-homophobic males
Personality Theory and Research
 Biological processes
– Eysenck’s research on arousal in the Ascending Reticular
Activating System (ARAS)
– Extraverts show less responsiveness to stimulation
– Introverts show heightened response to stimulation
– Implications for socialization frequency and interpersonal
distance
Measuring personality (description)
- Early examples were decidedly non-scientific
Early Assessment
Roots of Assessment
Early attempts..
 Palm reading
 Astrology - stars as gods vs. planets
All of these (non-standardized, unreliable and non-validated)
techniques rely on…
Barnum effect - broad and slightly positive statements;
– Stock statements - true in all circumstances
– Fishing statements – general statements that can be interpreted in
many ways (e.g., “you’ve experienced a loss”)
– Research (Glick, 1985) suggests that people are more likely to
believe Barnum-type false feedback vs. real personality
assessments.
Phrenology
Body Morphology
Morphological assessments: From the
head to the body
 Phrenology (Gall, early 1800s) – skull shape =
personality
 Sheldon’s body types (1950)
– Based on photographs of all incoming freshmen
at Ivy league schools in the 1930s
– Endomorph – jolly/happy, lazy
– Mesomorph – dominant, athletic
– Ectomorph – smart, shy
 Body type and criminality (Lombroso)
Current Assessment
Clinical settings:
 Psychodynamic methods: word association, TAT,
Rorschach (2nd most common test), etc.
 MMPI - developed in 1940 using an empirical
approach, revised in 1989 (MMPI-2) and has 567
T/F items
– Most widely used inventory in clinical settings
– items generally lack face validity (not obvious)
– 3 validity scales (lying, defensiveness,
infrequency)
– Assesses m/f, Si, Hs, Pa, etc.
(psychopathology= personality)
Assessment - continued
Non-clinical settings
 NEO-PI – developed for use in the non-clinical
population
– Neuroticism, Extraversion, Openness to new
experience, Agreeableness, &
Conscientiousness
– Neuroticism is associated with psychological
problems (depression, anxiety), but also
success in school and work.
– Internal control beliefs result in better adaptation
and health (studies in old age home; Rodin,
1977)
Intelligence - what is it?
 Cognitive abilities such as memory, vocabulary,
reasoning, general knowledge, speed of
responding, etc.
 Wechsler Adult Intelligence Scale (WAIS-III)
– Verbal and Performance IQ
– Mean IQ = 100, SD = 15
– Like all IQ measures, it is considered to be
culturally biased (no such thing as a culture
free test)
Alternatives to traditional intelligence
 Gould: Intelligence does not = IQ; does not reflect
innate skills, nor is intelligence unchangeable
(video)
 Broader definitions of intelligence: Gardner’s
multiple intelligences (abilities in music, art,
language, social skills, coordination, etc.)
 Creativity - a way to assess alternative forms of
intelligence (flexibility in how one thinks about a
problem- allows for novel responses and divergent
thinking –the consequences test)
Stunted intellectual development
Associated with several developmental disorders including
 Autism: extremely low IQ, minimal verbalizations, isolative, repetitious
(rocking) and sometimes self-damaging (head banging) behavior
 Autism spectrum disorders: 6 in 1,000 and these include Rett syndrome
(small heads, hands, feet, repetitive movements, cog delay), Asperger’s
(high functioning AD?), etc.
 More common in males (4:1), but females are more severe cases
Savant syndrome
 Very rare (only 1% of all autistic individuals: approx. 1 in a million)
 An extraordinary ability (either in absolute or relative to daily functioning),
severe cognitive deficits, over attention
Stimulus over-selectivity – over attention to only one aspect of a stimulus
(can explain both autism and savant syndrome)
Biases and heuristics in judgment
 General rules we apply in reasoning to be efficient
(can result in erroneous conclusions when
improperly applied)
 % violent crimes? = 10-11%
– The availability heuristic
Biases - cont
 The representative heuristic (ignores base
rates)
– Over 1 million truck drivers vs. 1 chair
– 10% are quiet, 1% like cognac, classical music
(1%) = 10
 What is your chance of getting skin cancer in the
next two years? What is the chance of someone of
the same age/gender as you getting skin cancer in
the next 2 years?
– Overconfidence bias
Biases and heuristics in judgment – cont.
 What are the next three numbers (2,4,6, _,_,_)?
– Confirmation bias
 The odds of winning at black jack are 50%. Assuming you
have just lost 10 hands in a row, what are your odds of
winning the next one?
– Gambler’s fallacy (luck will change) – in reality, these
are random and unrelated events. Luck doesn’t change.
 All-star team vs. a regular team, who should win?
– Fallacy of composition (the whole is = sum of its parts)
 Buying beef with 25% fat or 75% fat free?
– Error from framing effects – context provides information
that results in different conclusions