PSYC 300
Chapter 2 – Methods of Psychopathology
2.1 The Role of Paradigms
- A paradigm is a set of basic assumptions that outline the universe of scientific inquiry
A general perspective that defines how to conceptualize and study a subject, how to
gather and interpret relevant data, even how to think about a particular subject
- Science is bound by limitations imposed on scientific inquiry by the current state of knowledge
& whether scientists can remain objective when understanding and studying abnormal behaviour.
Science is not a completely objective and certain enterprise.
Thomas Kuhn philosopher of science believed subjective factors as well as limitations
in our perspective on the universe enter the conduct of scientific inquiry.
Kuhn believed paradigms are central to any application of scientific principles
- Paradigms have profound implications for how scientists operate and specify what problems
scientists will investigate and how they will go about the investigation
- A paradigm injects inevitable biases into the definition and collection of data (may affect the
interpretation of facts)
The meaning given to data may depend to a considerable extent on a paradigm.
- There are four major types of paradigms: biological, cognitive-behavioural, psychoanalytic, and
humanistic.
Psychodynamic & humanistic paradigms have become less influential over the years, but
some have modern applications that continue to have a significant impact.
- Abnormal behaviour tends to be multi-faceted, and contemporary views of abnormal behaviour
and its treatment tend to integrate several paradigms.
There are two highly influential paradigms the diathesis–stress and biopsychosocial
SUMMARY
- Scientific inquiry is a special way in which human beings acquire knowledge about their world.
- People may see only what they are prepared to see, and certain phenomena may go undetected
because scientists can discover only the things about which they already have some general idea.
- One is better able to keep track of subjective influences by making explicit one's paradigm, or
scientific perspective.
- The paradigm that is operating will guide the hypotheses that are tested and how the results and
their implications are interpreted.
2.2 Biological Paradigm
- Biological paradigm: a broad theoretical view that holds that mental disorders are caused by
some aberrant somatic process or defect.
- The biological paradigm of abnormal behaviour is a continuation of the somatogenic hypothesis.
This paradigm has often been referred to as the medical model or disease model.
Medical model: a conceptual model that maintains that dysfunction stems from internal
biological processes and factors within the individual & is more likely to reflect
psychiatry than psychology (also called disease model)
- The study of abnormal behaviour is linked historically to medicine.
Early & contemporary workers used the model of physical illness as the basis for
understanding deviant behaviour.
, In abnormal behaviour, terminology of medicine is pervasive medical illnesses differ
in their causes share one characteristic: some biological process is disrupted or not
functioning normally.
- Biological paradigm was the dominant paradigm in Canada and elsewhere from the late 1800s to
the middle of the 20th century.
Hall's (1900) use of gynaecological procedures to treat “insanity” in women from BC.
Maintained that “insanity exists when the Ego is dominated and controlled by the
influence from a diseased periphery nerve tract or center … the removal of a small part
of the physical disease might result in the restoration of the balance of power
Worked in removals of ovarian cysts or the entire ovaries as treatment for melancholia,
mania, and delusions.
Contemporary Approaches to Biological Paradigm
- There is extensive literature on biological factors relevant to psychopathology.
Heredity probably predisposes a person to have an increased risk of developing
schizophrenia
Depression may result from chemical imbalances within the brain
Anxiety disorders may stem from a defect within the autonomic nervous system that
causes a person to be too easily aroused
Dementia can be traced to impairments in structures of the brain
- Three areas of research within the biological paradigm are behaviour genetics, molecular
genetics, and biochemistry.
Behaviour Genetics
- When ovum (female reproductive cell) is joined by the male's spermatozoon, a zygote, or
fertilized egg, is produced.
46 chromosomes the number characteristic of a human being.
Each chromosome is thousands of genes, the carriers pass from parent to child.
Gene: an ultramicroscopic area of the chromosome smallest physical unit of the DNA
molecule that carries a piece of hereditary information.
- Behaviour genetics is the study of individual differences in behaviour that are attributable in part
to differences in genetic makeup.
Behaviour genetics studies the degree to which characteristics, e.g., physical
resemblance or psychopathology are shared by family members (shared genes)
Genotype: an individual's unobservable genetic constitution (totality of genes possessed)
o Genotype is fixed at birth but should not be viewed as a static entity.
o The total genetic makeup of an individual, consisting of inherited genes.
Phenotype: an individual's totality of his or her observable, behavioural characteristics,
such as level of anxiety.
o Phenotype changes over time and is viewed as the product of interaction
between genotype and the environment
o E.g., an individual is born with the capacity for high intellectual achievement,
but whether they develop their genetically given potential depends on
environmental factors as upbringing and education.
o Various clinical syndromes are disorders of the phenotype.
, - Genes controlling various features of development switch off and on to control aspects of
physical development.
- The study of behaviour genetics has relied on four basic methods to uncover whether a
predisposition for psychopathology is inherited: comparison of members of a family, comparison
of pairs of twins, the investigation of adoptees, linkage analysis.
- Family method can be used to study a genetic predisposition among members of a family
(average number of genes shared by two blood relatives is known)
Family method: a research strategy in behaviour genetics in which the frequency of a
trait or of abnormal behaviour is determined in relatives who have varying percentages
of shared genetic background.
Children receive a random sample of half their genes from one parent and half from the
other parents and their children are 50% identical in genetic background.
First-degree relative: people who share 50% of genes with a given individual
- If a predisposition for a mental disorder can be inherited, a study of family should reveal a
relationship between shared genes and the prevalence of the disorder.
- UBC twin study led by Kerry Jang and John Livesley is a long-term investigation of the
contribution of shared genes to personality factors and behavioural disorders.
Starting point collecting a sample of individuals who bear the diagnosis in question.
o These people are referred to as index cases, or probands.
o Index cases (probands): the person who in a genetic investigation bears the
diagnosis or trait in which the investigator is interested.
Relatives are studied to determine the frequency with which the same diagnosis might be
applied to them if genetic predisposition to the disorder is present, first-degree
relatives of the index cases should have the disorder at a rate higher than that found in
the general population.
o E.g., 10% of first-degree index cases relatives with schizophrenia can be
diagnosed as having it too, compared with about 1% of the general population.
- In the twin method, both monozygotic (MZ) twins and dizygotic (DZ) twins are compared.
Twin method: research strategy in behaviour genetics in which concordance rates of
monozygotic and dizygotic twins are compared.
Monozygotic (identical twins) develop from a single fertilized egg genetically the
same and are always the same sex
Dizygotic (fraternal twins) develop from separate eggs typically only 50% alike
genetically, can be the same or opposite sex
Twin studies begin with diagnosed cases and then search for the presence of the disorder
in the other twin
o Similar diagnostically concordant (similarity in psychiatric diagnosis or in
other traits within a pair of twins.)
o To find a predisposition for a mental disorder, concordance should be greater in
genetically identical MZ pairs than in DZ pairs.
o When the MZ concordance rate is higher than the DZ rate, the characteristic
being studied is said to be heritable
- The ability to offer a genetic interpretation of data from twin studies hinges greatly on what is
called the equal environment assumption.
Environment assumption: the environmental factors that are partial causes of
concordance are equally influential for MZ pairs and DZ pairs.
Chapter 2 – Methods of Psychopathology
2.1 The Role of Paradigms
- A paradigm is a set of basic assumptions that outline the universe of scientific inquiry
A general perspective that defines how to conceptualize and study a subject, how to
gather and interpret relevant data, even how to think about a particular subject
- Science is bound by limitations imposed on scientific inquiry by the current state of knowledge
& whether scientists can remain objective when understanding and studying abnormal behaviour.
Science is not a completely objective and certain enterprise.
Thomas Kuhn philosopher of science believed subjective factors as well as limitations
in our perspective on the universe enter the conduct of scientific inquiry.
Kuhn believed paradigms are central to any application of scientific principles
- Paradigms have profound implications for how scientists operate and specify what problems
scientists will investigate and how they will go about the investigation
- A paradigm injects inevitable biases into the definition and collection of data (may affect the
interpretation of facts)
The meaning given to data may depend to a considerable extent on a paradigm.
- There are four major types of paradigms: biological, cognitive-behavioural, psychoanalytic, and
humanistic.
Psychodynamic & humanistic paradigms have become less influential over the years, but
some have modern applications that continue to have a significant impact.
- Abnormal behaviour tends to be multi-faceted, and contemporary views of abnormal behaviour
and its treatment tend to integrate several paradigms.
There are two highly influential paradigms the diathesis–stress and biopsychosocial
SUMMARY
- Scientific inquiry is a special way in which human beings acquire knowledge about their world.
- People may see only what they are prepared to see, and certain phenomena may go undetected
because scientists can discover only the things about which they already have some general idea.
- One is better able to keep track of subjective influences by making explicit one's paradigm, or
scientific perspective.
- The paradigm that is operating will guide the hypotheses that are tested and how the results and
their implications are interpreted.
2.2 Biological Paradigm
- Biological paradigm: a broad theoretical view that holds that mental disorders are caused by
some aberrant somatic process or defect.
- The biological paradigm of abnormal behaviour is a continuation of the somatogenic hypothesis.
This paradigm has often been referred to as the medical model or disease model.
Medical model: a conceptual model that maintains that dysfunction stems from internal
biological processes and factors within the individual & is more likely to reflect
psychiatry than psychology (also called disease model)
- The study of abnormal behaviour is linked historically to medicine.
Early & contemporary workers used the model of physical illness as the basis for
understanding deviant behaviour.
, In abnormal behaviour, terminology of medicine is pervasive medical illnesses differ
in their causes share one characteristic: some biological process is disrupted or not
functioning normally.
- Biological paradigm was the dominant paradigm in Canada and elsewhere from the late 1800s to
the middle of the 20th century.
Hall's (1900) use of gynaecological procedures to treat “insanity” in women from BC.
Maintained that “insanity exists when the Ego is dominated and controlled by the
influence from a diseased periphery nerve tract or center … the removal of a small part
of the physical disease might result in the restoration of the balance of power
Worked in removals of ovarian cysts or the entire ovaries as treatment for melancholia,
mania, and delusions.
Contemporary Approaches to Biological Paradigm
- There is extensive literature on biological factors relevant to psychopathology.
Heredity probably predisposes a person to have an increased risk of developing
schizophrenia
Depression may result from chemical imbalances within the brain
Anxiety disorders may stem from a defect within the autonomic nervous system that
causes a person to be too easily aroused
Dementia can be traced to impairments in structures of the brain
- Three areas of research within the biological paradigm are behaviour genetics, molecular
genetics, and biochemistry.
Behaviour Genetics
- When ovum (female reproductive cell) is joined by the male's spermatozoon, a zygote, or
fertilized egg, is produced.
46 chromosomes the number characteristic of a human being.
Each chromosome is thousands of genes, the carriers pass from parent to child.
Gene: an ultramicroscopic area of the chromosome smallest physical unit of the DNA
molecule that carries a piece of hereditary information.
- Behaviour genetics is the study of individual differences in behaviour that are attributable in part
to differences in genetic makeup.
Behaviour genetics studies the degree to which characteristics, e.g., physical
resemblance or psychopathology are shared by family members (shared genes)
Genotype: an individual's unobservable genetic constitution (totality of genes possessed)
o Genotype is fixed at birth but should not be viewed as a static entity.
o The total genetic makeup of an individual, consisting of inherited genes.
Phenotype: an individual's totality of his or her observable, behavioural characteristics,
such as level of anxiety.
o Phenotype changes over time and is viewed as the product of interaction
between genotype and the environment
o E.g., an individual is born with the capacity for high intellectual achievement,
but whether they develop their genetically given potential depends on
environmental factors as upbringing and education.
o Various clinical syndromes are disorders of the phenotype.
, - Genes controlling various features of development switch off and on to control aspects of
physical development.
- The study of behaviour genetics has relied on four basic methods to uncover whether a
predisposition for psychopathology is inherited: comparison of members of a family, comparison
of pairs of twins, the investigation of adoptees, linkage analysis.
- Family method can be used to study a genetic predisposition among members of a family
(average number of genes shared by two blood relatives is known)
Family method: a research strategy in behaviour genetics in which the frequency of a
trait or of abnormal behaviour is determined in relatives who have varying percentages
of shared genetic background.
Children receive a random sample of half their genes from one parent and half from the
other parents and their children are 50% identical in genetic background.
First-degree relative: people who share 50% of genes with a given individual
- If a predisposition for a mental disorder can be inherited, a study of family should reveal a
relationship between shared genes and the prevalence of the disorder.
- UBC twin study led by Kerry Jang and John Livesley is a long-term investigation of the
contribution of shared genes to personality factors and behavioural disorders.
Starting point collecting a sample of individuals who bear the diagnosis in question.
o These people are referred to as index cases, or probands.
o Index cases (probands): the person who in a genetic investigation bears the
diagnosis or trait in which the investigator is interested.
Relatives are studied to determine the frequency with which the same diagnosis might be
applied to them if genetic predisposition to the disorder is present, first-degree
relatives of the index cases should have the disorder at a rate higher than that found in
the general population.
o E.g., 10% of first-degree index cases relatives with schizophrenia can be
diagnosed as having it too, compared with about 1% of the general population.
- In the twin method, both monozygotic (MZ) twins and dizygotic (DZ) twins are compared.
Twin method: research strategy in behaviour genetics in which concordance rates of
monozygotic and dizygotic twins are compared.
Monozygotic (identical twins) develop from a single fertilized egg genetically the
same and are always the same sex
Dizygotic (fraternal twins) develop from separate eggs typically only 50% alike
genetically, can be the same or opposite sex
Twin studies begin with diagnosed cases and then search for the presence of the disorder
in the other twin
o Similar diagnostically concordant (similarity in psychiatric diagnosis or in
other traits within a pair of twins.)
o To find a predisposition for a mental disorder, concordance should be greater in
genetically identical MZ pairs than in DZ pairs.
o When the MZ concordance rate is higher than the DZ rate, the characteristic
being studied is said to be heritable
- The ability to offer a genetic interpretation of data from twin studies hinges greatly on what is
called the equal environment assumption.
Environment assumption: the environmental factors that are partial causes of
concordance are equally influential for MZ pairs and DZ pairs.
