Thursday, February 5, 2015
Chapter 7: Physiological Approaches to Personality
-studies have show that traumatic brain injury can lead to large changes in personality
due to the fact of having the diminished ability to control impulses and self control.
this lack is probably due to disruptions between the frontal lobes in which serve as
the executive control centre of the brain.
-an advantage of the physiological approach is that these characteristics can be
measured mechanically and reliably.
-physiological characteristics: the functioning of organ systems within the body. ex:
nervous system, cardiac, muscle/skeletal. - they are important for the maintenance of
life and serve as studies for medicine, anatomy and physiology.
For ex: people differ from one another as to how sensitive their nervous system are
thus, this approach assumes that differences in physiological characteristics are related
to important differences in personality and behaviour patterns. another important
characteristic is simplicity. often theories simply state that a physiological difference
results in a personality difference or a difference in behaviour pattern due to the fact that
some may have efﬁciency of a certain chemical in their nervous system.
only one cause to explaining behaviour it is not destiny.
Physiological Approach to Personality
-the typical research question posed is their concerns whether some people will
exhibit more or less of a speciﬁc physiological response than others under certain
-they must be able to build a theoretical bridge (correlation between two things)
between the personality dimensions and the physiological variables.
Physiological Measures used in Research
-most is obtained by electrodes, or sensors that are placed on one’s skin surface. one
drawback to this measure is that the person is literally wired to the recording machine
which means that movement is restrained.
-a new generation of electrodes will overcome this limitation through telemetry where
the signals are sent through polygraphic radio waves instead of wires.
-the skin on palms and feet have sweat glands that are directly inﬂuenced by the
sympathetic nervous system (autonomic nervous system) - the one that prepares the
Thursday, February 5, 2015
body for action such as ﬂight or ﬁght mechanism, when it is activated they are ﬁlled
with salty water.
-the more water that is present on the skin, the more easily the skin carries electricity.
this is known as skin conductance. the difference in the amount of electricity passed
into the skin at one electrode and the amount detected at the other electrode tells
how well it is conducting.
-some people show skin conductance even when there is an absence of external
stimuli. those that are in chronic activation such as anxiety or high neuroticism.
-blood pressure is the pressure exerted by the blood on the inside of the artery walls,
and it is typically expressed with two numbers: systolic (large # referring maximum
pressure within the system when the heart muscles contract) diastolic (small #
referring to the resting pressure inside the system between the contractions. - they
are both activated through the sympathetic nervous system (ﬁght or ﬂight)
-another easily obtained is through the heart rate (BPM) - one approach is to measure
the time intervals between successive beats. one interval is 60 MP. it is important
because the more it increases the more it is preparing one for action as well as
increases with cognitive effort of a task. (some show larger increases known as
-related with type A personality: impatience, hostility, competitiveness - leads to heart
attack, disease and artery disease.
-electrodes placed on the scalp such as EEG’s which can obtain different parts of the
brain while someone is sleeping, relaxed or doing a task. it may tell us about patterns
and what regions use what processes and tasks. we want to know whether people
have different processes for the same activity.
-another way is through the evoked potential technique where the EEG is measured
but the person is given a stimulus and tests their response.
-imaging techniques such as: PET or fMRI (mapping the structure and function of the
-the fMRI allows to look inside the working brains to see which parts are active during
a task. they found that personality correlated with the degree of brain activation in
response to negative and positive images.
ex: neuroticism correlated with the frontal lobe is related to negative while extraversion
with high frontal lobe is positive) the big ﬁve are also a good supporter.
myths: bumps and size does not inﬂuence the function of the brain