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John Stern – defined the work of psychophysiology
It is equally tenable to manipulate physiological variables and examine behavioural changes.
Subset of people who study this – now known as biological psychologists, psychobiologists, or behavioural
Most psychophysiologists – study the responses of humans rather than nonhuman animals; therefore, such
researchers must limit their techniques of data collection to the surface recording of bioelectric signals.
Electrodes are attached to the skin over the organ of interest.
Do not greatly interfere with normal behaviour.
Because the recordings are from the surface of the brain, psychophysiologists must sacrifice some degree of
immediate biological actitude.
Researchers can simply ask the patient to describe how they feel instead of making assumptions about their
feelings state based on observable behaviour.
Short and Long History
Began in the 1950s
R.C. Davis and a group composed of other psychologists met informally – in 1960 they organized the Society
for Psychophysiological Research, with Chester Darrow as the President.
Albert Ax – began a newsletter – which developed into the Journal Psychophysiology.
GSR – was the first type of measurement used, whereas brain-recording articles were non-existent in the first
issue of the Journal.
Early Greeks – Plato suggested tripartite organization – rational faculties were located in the head,
passions were said to be located in the spinal marrow, which related them to the heart. The instincts, or lower
appetites, were said to be located in the spinal cord.
Because of his belief that our senses deceive us, Plato rejected the idea of experimentation and placed pure
thought above empirical observation as the means to achieve knowledge.
Chinese medicine – also rejected dissection and relied on more holistic concepts of human physiology and
Renaissance – Mesulam + Perry (1972) – have shown there was considerable empirical sophistication in the
writings of Erasistratos, Galen, and Ibn Sina.
Erasistratos – a physician – story of how his son fell in love with his step mother and almost died out of
misery because he couldn't be with her – this was depicted as a problem of the mind that influenced the body.
oThis is the beginning of stimulus-response specificity.
Galen – father of modern physiology, also a physician – reported a similar case of lovesickness.
oBased on irregular pulse when lover was present.
Ibn Sina – psychophysiological principles – he utilized the method of elevated pulse rate to determine the
person with whom one was in love.
Electrical Properties of the Skin
Luigi Galvani – demonstration that animals produce electricity that originates within the organism itself.
oOne theory – suggested that diseases could be diagnosed by measuring changes in the distribution
of electrical current in the body.
oSecond theory – stated that there was a connection between electricity, animal magnetism,
suggestibility, and hysteria.
oTransfert – by Charcot , was the movement through utilization of a magnet hysterical symptoms
were transferred from side to side of the body.
Vigouroux – may have provided us with the first documentation of the habituation of skin resistance, that is,
the diminution of a response to repeated stimulation.
Fere – performed research that utilized hand dynamometer.
oTrying to find some measure of excitation in the nervous system.
oCurrent applied to the anterior surface of the forearm
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Mueller, Veraguth, and Jung – helped bring international attention to the study of skin resistance.
oMueller – observed that changes in skin resistance appeared to correlate with changes in
oConnection between Mueller + Veraguth – found a new reflex, sensitive to emotional factors.
oJung (1907)– combined the measure of skin resistance with a word-association procedure.
100 words were said to participant who was told to answer as quickly as possible with
Concluded that skin resistance responses were related to attention to the stimulus and the
ability to associate it with previous occurrences, either conscious or unconscious.
Physical stimuli elicit a greater response that psychological ones – greater in normal
populations compared to pathological ones.
1st instrument capable of reproducing a continuous record of rapidly changing bioelectrical event was the
capillary electrometer developed in the 1870s by Marey
oTube filled with sulfuric acid and mercury – electrical activity would change the shape of the
mercury meniscus, which would form the basis for recording.
oRecorded and displayed the electrical activity of a frogs heart
o1887 – Waller first recorded electrical activity from the human heart using electrodes on the skin.
String Galvanometer – Einthoven – father of electrocardiography
oDeveloped in the 1900s, but finalized in 1940.
1929 – Berger – first human electroencephalogram (EEG). EEG related to eye opening, large scale stimuli,
and mental activity and attention
IC and PC – integrated circuit and Personalized Computer – have both caused the rapid increase in the field
of psychophysiological instrumentation
3 types of activity:
2.Tonic (background); and;
3.Phasic (evoked responses)
(1) Spontaneous –
oSame as a response to a known stimulus such as a tone, a shock, or a snake. It may take the form of
a change in the heart rate or skin conductance in the palm of the hand, muscle potential, and so on.
oIn reality, spontaneous activity is a change in physiological activity that occurs in the absence of
any known stimuli.
oOf interest? – BC important to be aware of these responses to avoid misinterpretation. –
(2) Tonic –
oReferred to as the background level or resting level of activity of a particular physiological
oTonic level is simply the level of activity of some ANS or CNS measure at a particular point in time
prior to stimulation.
oInterest? – BC in its own right is a measure of activity without stimulus – hypertension for example
has different resting potentials.
2nd reason – some cases the size of a response to a specific stimulus depends upon the
tonic level as measured immediately prior to the stimulus.
(3) Phasic –
oDiscrete response to a specific stimulus – an evoked response.
oThe most important factor to consider when quantifying phasic activity is that the subjects’
response to, for example, a slide of an American flag is not being made against a background of
zero activity. The subject is constantly responding to internal as well as external stimuli – somatic
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Process by which oxygen is supplied to cells and carbon dioxide is removed.
Breathing rate, and amplitude are the two measurements we are interested in.
oNormal rate of respiration – 12-16 breaths per minute.
oUsual depth (tidal volume) is about 400-500 ml for healthy adults.
Direct or indirectly measured:
oDirect – also allow one to assess nature and amounts of gases like CO2 that are being expired from
the lungs. Also the inspiratory duty cycle can be measure directly, which is the ratio of inspiratory
duration to the total respiratory cycle duration.
Mean inspiratory flow – another measure that provides important information about the
CNS on respiration. – it appears to reflect central inspiratory drive and it can be
quantified using the ratio of tidal volume to inspiratory duration.
Often used as a check for possible artifacts in other response measures caused either by breathing
irregularities or by changes in breathing due to an experimental manipulation that might confound the
measure of interest, such as HR.
Deep breath – intentional or not, can often bring about a greater change in ANS function than will
manipulation of the independent variable.
oEx – Stern + Anschel – had subjects take 4 different types of breaths and recorded the effects on
finger pulse volume, HR, and skin resistance.
Extent of ANS disturbance varied directly with the depth of the inspiration. Deeper
breaths leading to a decrease in skin resistance and increase followed by a decrease in
HR, and vasoconstriction in the finger.
RSA – respiratory Sinus Arrhythmia – Ludwig (1847) – refers to the rhythmic increases and decreases in HR
produced by normal respiration in many subjects.
oAs a person inhales, the heart rate increases – as the person exhales, the heart rate decreases.
oArises from both afferent connections from the lungs to CNS, and from CNS respiratory rhythm
oProvides a reasonable estimate of the effects of the Parasympathetic nervous system on the heart,
and is particularly useful BC it is measured uninvasively.
Modified by both CNS and ANS – specifically PNS
Medulla and pons contain respiratory areas – contain respiratory generator neurons which spontaneously fire
bursts of action potentials that initiate inspiration.
Connections to the cortex, the hypothalamus, and other brain stem areas. In addition, several autonomic
reflexes arising from the lungs, upper airways, heart, and blood vessels also modify respiration.
Hering-Breuer reflex – inhibits inspiration and prevents further over-inflation of lungs, it does not operate
during normal respiration, but appears to protect against over-inflation.
Highly responsive to changes in Oxygen and CO2
oChemosensitive areas on the brainstem are part of the respiratory center and are directly stimulated
by an increase of hydrogen ions in the cerebrospinal fluid, which is highly dependent on levels of
oCO2 is much more important in the regulation of respiration than oxygen
Mechanical changes in thorax
oAccompany inspiration and expiration are particularly important for psychophysiology BC they are
noninvasively measurable aspects of breathing.
oJust before inspiration begins, the diaphragm is relaxed, and in this state it forms a dome-shaped
structure that juts up into the area below the ribcage. Also some muscles that attach to adjacent ribs
are relaxed therefore ribs slant downward and forward from their attachments to the spine.
oWhen inspiration is initiated, the diaphragm contracts and flattens, which creates a negative
pressure in the thorax which forces the lungs open. Intercostal muscles contract which raises the
ribs so they are more nearly perpendicular with the spine and also puts the sternum forward.
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