The Science of Psychology

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Chapter 1

• The Science of Psychology

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Chapter 1
Fields of Psychology gt empirical gt
applied Roots of Psychology gt Philosophical
Roots gt Biological Roots Major Trends in
Psychology
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Chapter 1
Fields of Psychology Empirical
Physiological Psychology Attempts to understand
behaviour at the level of the brain itself. gt
drug studies linked to neurotransmitters gt brain
surgery and other invasive methods gt often uses
animals due to ethical considerations e.g.,
Rabbit studies relevant to epilepsy awakenings
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Psychophysiology Attempts to understand
behaviour by examining peoples physiological
reactions gt changes in heart rate, blood
pressure, electrical resistance muscle
tension, and electrical activity in the brain
resulting from various circumstances e.g.,
Brain waves during sleep Comparative
Psychology Attempts to understand behaviour by
examining patterns across different species gt
Often a focus on Evolutionary adaptiveness, and
environmental considerations e.g.,
Changing size of brain areas linked to mating
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Behavioural Psychology Focuses only on the
links between stimuli and the behaviours they
give rise to gt believe that talking in terms
of mind or consciousness is
unscientific gt only stimuli and behaviour can be
measured gt strong focus on the effects of
punishment and reward e.g., training a dog
to behave Behaviour Genetics Examine the role
that genes play in the determination of
behaviour gt often examine blood relatives or
use breeding studies e.g., twin studies of
the role of genetics on intelligence
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Cognitive Psychology Attempts to understand
behavior in terms of the processes and mechanisms
that underlie it gt Often conducts computer
based experiments with human subjects gt
usually focussed on relatively high level issues
such as how memory, attention, or awareness
work gt reverse-engineering model .. Software
emphasis e.g., state-dependent
learning Perception Similar to above except
that focus is much more strongly on basic sensory
processes such as vision or audition e.g.,
psychophysics detection criteria pot study
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Neuropsychology Attempts to understand
behaviour through a higher-level analysis of
links between brain structure and performance gt
effects of brain injury on performance gt imaging
studies, typically linked to cognitive-type
experiments e.g., The man who mistook his wife
for a hat Developmental Psychology Examines
how the processes or mechanisms of the brain
change with time gt major focus on children ..
more recent focus on elderly gt often combined
with perception or cognition theories or
procedures e.g., the development of motor
processes
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Social Psychology Examines the effects of
social factors on an individuals behaviour gt
studies sometimes involve deception or
confederates gt often look at things like
conformity, attitudes and prejudice e.g.,
studies of conformity to authority Personality
Psychology The study of individual differences
in performance due to stable characteristics gt
often uses questionnaires to assess relevant
personality characteristics then uses the
results of these questionnaires to predict
performance e.g., magazine know yourself
surveys personnel surveys .. profiles
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Cross-cultural Psychology Examines cultural
effects on the attitudes and behaviours of
humans gt often focuses on the enduring effects
of customs and cultural environments on
behaviour and thinking e.g., fear of
dogs Clinical Psychology Attempts to
understand (and change) behaviour by focusing on
groups with behaviour problems gt focus on
therapy and talk e.g., Frasier
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Fields of Psychology Applied
Clinical Neuropsychologist Typically work in
hospitals attempting to help patients with
various neurological problems such as head
injury Health Psychologist Promote behaviour
and lifestyles that maintain health and prevent
illness School Psychologist Deal with the
behavioural problems of students in school
basically clinicians in a school setting
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Consumer Psychologist Study the learning and
motivation of buying behaviour. May help with
marketing, or not Community Psychologist
Concerned with the welfare of individuals in the
social system, especially disadvantaged people.
Typically, they are interested in changing the
system, not the people Organizational
Psychologist (IO) Deal with psychological
issues in the workplace. For example, what
conditions lead to the highest degrees of
comfort, loyalty, and especially productivity
from the workers? Engineering Psychologists
(ergonomics of human factors) Focus on
facilitating human/machine interactions
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The Philosophical Roots of Psychology
The concept of intelligence is like the concept
of magic, it only holds any validity when we
dont know how its done What about the will, the
soul, or consciousness? Early in human history,
humans would attribute souls or wills to almost
anything a behaviour termed animism In fact,
we still fall into those habits today gt Zippy
Ralph gt Thunder and Lightening
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However, once we understand the true causes of
certain events the attribution of a soul often
disappears So what of human behaviour? If we
ever completely understand the causes of human
behaviour, will there be room left for a human
soul? Rene Descartes (1596-1560). Believed that
the human body, and many of its responses, could
be thought of as a highly complex
machine However, Descartes also believed that
humans possess a soul and free will a concept
called dualism gt what if we assume no soul? No
free will?
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John Locke (1632-1704) went a step further then
Rene in assuming that even the mind could be
thought of as a machine He also strongly
advocated the practice of empiricism, the
pursuit of truth through observation and
experience Contrary to the notion of innate
ideas, Locke assumed that all knowledge was
acquired through experience alone Basically,
Locke and others (e.g., Berkeley, see text)
were attempting to understand learning, and we
are still trying to understand that today The
notion that the mind can be thought of as a
machine, and that humans are no different from
animals, in one termed materialism (James Mill,
1773 - 1836) and it remains the dominant
scientific assumption to this date
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The Biological Roots of Psychology
Although Descartes notion of the body as a
hydraulic machine did not hold up, Luigi Galvani
(1737-1798) and several unnamed frog matyrs) did
support the notion of the body as an electric
machine Johannes Muller (1801-1858) was the
first to systematically study human anatomy and
in his Doctrine of Specific Nerve Energies
noted that the basic message sent along all
nerves was the same an electrical impulse What
differentiates between impulses is where they
arise, and where they go Leads to the
implication of specialized brain regions
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The implications of Mullers work were confirmed
by ablation studies performed by Pierre Florens
(1774-1867) the result of removing part of the
brain depends on which part is removed Paul
Broca (1824-1880) was the first to apply this
logic to humans when he performed an autopsy on a
stroke victim and claimed to find the speech
center of the brain gt Check out Brocas
Brain by Sagan Gustav Fritsch Eduard Hitzig
(1870) added further evidence using electrical
stimulation studies body appeared to be mapped
on the surface of the brain gt the Phrenology
phenomenon
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Other stage-setting contributions
Hermann von Helmholtz (1821-1894) championed the
notions of objective investigation and precise
measurement gt speed of nerve impulses Ernst
Weber (1795-1878) showed that peoples ability
to discriminate between similar weights (or
flashes of light) followed a natural function of
the difference between the weights (or
lights) gt thus, subjective states could be
measured and seem to follow natural laws
psychophysics
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The Birth and Early Years of Psychology
The first Psychologist was Wilhelm Wundt
(1832-1920). He believed that all things,
including the mind, could be studied
scientifically. His text book Principles of
Physiological Psychology was the first ever
Psychology textbook. Wundt believed that via
introspection, one could come to understand the
ideas and sensations that formed the
building blocks of consciousness this school of
Psychology is called Structuralism His approach
died out because of difficulties observers had
in reporting low level sensations, unaffected by
experience
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Partially as a consequence of the ideas of Darwin
(1809-1882) psychologists began to focus on
process of conscious activity rather than on its
structure This new school of Psychology was
termed Functionalism as it assumed that thinking
performed a function, that being to produce
useful and adaptive behaviours One of the
strongest proponents of functionalism was
William James (1842-1910) his ideas are still a
major influence Differences from Structuralism
gt focus on mental operations, not mental
structures gt processes studied as part of
the biological activity of the organism
evolutionary history and value gt studies the
relation between environment and response
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During the rise of functionalism, another person
was doing research largely on his own despite
this Hermann Ebbinghaus (1850-1909) had a large
impact on experimental psychology Ebbinghaus
wanted to study memory and forgetting with the
same scientific rigor that others had studied
sensation (e.g., Fechner) Used nonsense syllabus
as stimuli (e.g., FIK, LOP) in order to prevent
contamination by previously learning Specified
procedures that would allow memory (and
forgetting) to be measured in precise ways,
rather than relying on introspection and common
sense gt e.g., unlearning procedure contrast
with structuralist
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Into this mix we now add a young neurologist
named Sigmund Freud (1856-1939) who became
especially interested in behavioural and
emotional problems formulating
his psychodynamic theory of personality This
really marked the beginning of clinical
psychology, and psychiatry. His influence in
these areas is still huge today His work was
based on observation of patients, not on
experiments. The medical model is prevalent in
his views of disfunction His ideas we a mix of
structures and functions and he strongly pushed
the notion of unconscious influences on
behaviour Well hear plenty more on his later in
the course
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The next trend or school in Psychology was
behaviouralism, and it went much further in
limiting the subject matter of psychology to only
the relation between peoples environment, and
their behaviour argued that mental events
which cannot be directly observed cannot be
studied scientifically and had no place as part
of psychology Examples Law of Effect
Thorndike (1874-1949) Classical
Conditioning Pavlov (1849-1936) Establishment as
a School Watson (1878-1958) Behaviourism is
still an active school of psychology, and one of
the most famous behaviourists died quite recently
(Skinner, 1904-1990)
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Gestalt Psychology stressed the fact that
sometimes the whole of a percept is more than
the sum of its parts (Wertheimer,
1880-1943). Humanistic Psychology is a
school of psychology that focusses on human
experience, choice, creativity and positive
growth Pushes a greater emphasis on
understanding those qualities that make us
human Problem investigating these things in an
objective manner
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Breaking the Chains of Behaviourism
Recently (i.e., since the 60s) researches began
to again believe that the mind can be studied
scientifically. This cognitive revolution relies
strongly on the use of indirect methods of
measuring cognitive processes and structures For
Example
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Breaking the Chains of Behaviourism
Recently (i.e., since the 60s) researches began
to again believe that the mind can be studied
scientifically. This cognitive revolution relies
strongly on the use of indirect methods of
measuring cognitive processes and structures For
Example
RED GREEN BLUE RED GREEN RED BLUE GREEN BLUE
RED GREEN BLUE GREEN BLUE RED BLUE
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Breaking the Chains of Behaviourism
Recently (i.e., since the 60s) researches began
to again believe that the mind can be studied
scientifically. This cognitive revolution relies
strongly on the use of indirect methods of
measuring cognitive processes and structures For
Example
RED GREEN BLUE RED GREEN RED BLUE GREEN BLUE
RED GREEN BLUE GREEN BLUE RED BLUE
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The New Biological Revolution
Due to recent advances in brain imaging,
biological factors underlying psychology have
undergone a renaissance that continues on Some
Cognitive Psychologists are skeptical of what is
gained from these methods, whereas others are
combining some of these techniques with
cognition procedures forming a new field of
psychology termed Cognitive Neuroscience The
contrast brings up an interesting distinction
between what the brain does and where in
the brain it is done