PSY290 - Lecture 1

Definitions of terms + critical historical figures

Aristotle’s view

• father of science

argued that the brain’s purpose was to cool the blood and that the psyche resided in the heart

Hippocrates’ view

• father of medicine

argued for major role of the brain in behavior and for the role of humors

humors

internal fluids

Galen’s view

• physician

argued for major role of the brain in behavior and that ventricles were critical

who provided the first brain drawings?

Willis and Wren

Gall’s view

argued for localized brain function and experience dependent neuroplasticity

localized brain function

different brain regions have different functions

experience dependent neuroplasticity

brain areas develop with use

• suggested by Descartes Spurzheim

how is Descartes’ fluid model consistent with dualism?

because he argues that the brain and mind are separate

• the brain is for simple functions while the mind is for complex functions

Descartes’ view

argued that the pineal gland was the site of interaction between the brain and the mind

Holistic view

every part of the brain participates in every function

Ramon Y Gajal

• father of modern neuroscience

advanced staining procedures used by Golgi to visualize nervous system

argued that nervous system was made of discrete individual cells rather than being a single continuous network

neuron doctrine

nervous system is made of discrete individual cells

reticular theory

nervous system is a single continuous network

Sherrington

argued that the synapse was the functional connection between neurons

Who confirmed Sherrington’s theory?

Palay

Brodmann Map

The 52 Brodmann areas of the brain have assigned functions like motor function and cognitions

Brodmann areas

the 52 distinct brain areas making up the brain

Cellular connectionist theory

independent cells exist and form groups connecting with each other to mediate behaviors

what is the intermediate perspective between the localized function view and the holistic view?

the cellular connectionist view

Compensation in the context of injury

if one area in the cell network is damaged another might adjust to takeover its function

Otto Loewi

pharmacologist who was the first to identify a neurotransmitter

what was the first identified neurotransmitter?

acetylcholine

Who described the characteristics of action potential?

Eccles, Hodgkin and Huxley

Ethical perspective on animal models

in order to infer causal relationships for experimental designs

Reductionist/Logistic perspective on animal models

they have a simple nervous system so they are more convenient to study

Evolutionary perspective

similarities in the nervous system of species explain behavioral similarities

Comparative perspective

nervous system differences between species explain behavioral differences

Limitations of animal models

• expensive

• not the most accurate representation of human behavior (animals can’t speak)

• not always generalizable

what are the symptoms of depression?

• anhedonia

• fatigue

• low self worth/feelings of guilt

• disturbances in sleep, appetite and activity

• concentration difficulties

• suicidal ideations

anhedonia

absence of pleasure-seeking, loss of interest in activities normally enjoyed

behavioral despair

• used to model depression in animals by demonstrating how they stop struggling in an inescapable situation

Forced Swim Test

seeing how long an animal tries to escape the water before giving up

• models behavioral despair

Tail Suspension Test

suspending mice by the tail

• used to screen antidepressants

• model for behavioral despair

Sucrose Preference Test

Sees whether the mice prefer the water with sugar vs without and they preference for plain water indicates anhedonia

• model for anhedonia

What animal has a comparable brain structure to humans?

Chimpanzees

How did Becky the Chimpanzee’s behavior change after lesion to the prefrontal cortex?

She was no longer upset when making errors in behavioral tasks

Moniz

developed a treatment called frontal leukotomy that initially had positive results leading to widespread application of the procedure but inevitably caused permanent damage to the PFC because the experimental method was not used

What was Moniz’s theory of PFC damage?

he argued that prefrontal cortex damage could help treat mental illness

What were the key mistakes of Moniz’s procedure?

• experimental method was not used

• case study so not generalizable

• species differences was ignored

• limited follow up

• ignored individual rights

gene

unit of heredity transferred from parent to offspring

• 50% genetic material from father and 50% from mother

DNA

makes up a gene

nucleotides

arranged in a string to make up DNA

nucleotide sequence

base pair sequence/code of the gene

• determines where it is going

regulatory sequences

• regulates the expression of the gene

coding sequences

determine the structure of the gene’s product

what are the key proteins in the nervous system?

• enzymes

• receptors

• cytoskeletal parts

• transporters

polygenic traits

characteristics influenced by 2 or more genes

monogenic traits

trait produced by the effect of a gene or an allele

• tendency to be disordered

heritability estimate

proportion of variability in a trait that is explained by genetics

• h2= Vg/Vp ( variability due to genetics / the variability of the phenotype

• higher h2, more likely that the trait is driven by genetic factors

variability of the phenotype

the sum of the variability due to genetics and the variability due to the environment

what diseases in the nervous system are linked to a single gene of very strong effect?

• Huntington's disease (dementia)

• Phenylketonuria (mental retardation)

• Tay-Sachs Disease

• Charcot-Marie-Tooth Syndrome

pleiotropy

one gene can serve many functions

Epigenetics

study of meiotically or mitotically heritable changes in gene expression/function that cannot be explained by changes in DNA sequence

• why monozygotic twins are different

• alcohol tolerance with drinking