Intro to PSYCO 275 Flashcards
Biopsychologists
Measure biological, physiological, and genetic variables to relate to behavioural or psychological outcomes
Niko Tinbergen’s Four Questions
Offers categories of explanations for animal behaviour
- Mechanism = how does this behaviour occur in an individual?
- Ontogeny = how does this behaviour arise in an individual?
- Adaptive value = why is this behaviour adaptive for the species?
- Phylogeny = how does this behaviour arise in the species?
Reductionism
We study the brain using reductionist methods
We need to study the brain at its simplest components
Rely on non-human animal models or neuroimaging techniques
Allows scientists to confidently establish cause and effect, removing confounding variables
Advantages of Using Human Subjects
Communication -provide feedback -report experiences -follow instructions Have human brain and behaviour Low maintenance Cost-effective
Disadvantages of Using Human Subjects
Ethics limit reductionist methods
Attrition when studied repeatedly
Uncontrolled lifestyle
Disease transmission = new barrier with COVID 19
Comparative Approaches
Insight into the functional and behavioural differences of the brain using non-human subjects
There is homology in chemical and anatomical attributes
There are fundamental brain-behaviour interactions between species
Advantages of Using Non-Human Subjects
Invasive = can study in vitro or in vivo Direct measurements of brain and behaviour Can manipulate the brain Controlled lifestyles Simple nervous systems Less ethical constraints
Disadvantages of Using Non-Human Subjects
Cannot communicate
High maintenance
Ethics cost
How do we progress in science?
From converging operations
Use different approaches to focus on the same problem
Weakness in some approaches are made up by strengths of other approaches
Together can answer questions that not one approach can answer alone
The Goal of Descriptive Studies
To create a snapshot of the current state of affairs
Real-world
Advantages of Descriptive Studies
Provides a relatively complete picture of what is occurring at a given time
Allows the development of questions for further study
HIGH EXTERNAL VALIDITY
Disadvantages of Descriptive Studies
Does not assess relationships among variables
May be unethical if participants do not know they are being observed
LOW INTERNAL VALIDITY
The Goal of Correlational Studies
To assess the relationships between and among two or more variables
Advantages of Correlational Studies
Allows testing of expected relationships between and among variables and the making of predictions
Can assess these relationships in everyday life events
HIGH EXTERNAL VALIDITY
Disadvantages of Correlational Studies
Cannot be used to draw inferences about the causal relationships between and among variables
LOW INTERNAL VALIDITY
The Goal of Experimental Studies
To assess the causal impact of one or more experimental manipulations on a dependent variable
Advantages of Experimental Studies
Allows drawing of conclusions about the causal relationships among variables
HIGH INTERNAL VALIDITY
Disadvantages of Experimental Studies
Cannot experimentally manipulate many important variables
It May be expensive and time-consuming
LOW EXTERNAL VALIDITY
Experiments
Study causation
Randomly assign subjects into control and experimental groups
Manipulate an independent variable
-observe and measure the effects of manipulation
Within Subjects Design
All participants take part in every condition
Disadvantage = repeated measures = practice or adaptation effects
Between Subjects Design
Different people test each condition
Why do we want to keep experiments simple?
To avoid confounding or extraneous variables
Treatment of the control vs experimental conditions should be the exact same outside of the manipulation of the independent variable
Correlational Research
Quasi-Experimental Studies
Take measurement of 2 or more variables from the same individual and relate them
-eg. alcohol consumption and brain volume
-would be unethical to assign groups, we need already assigned groups
Correlation vs Causation
Correlation does not equal causation
Groups are self-assigned (in the alcohol case) and cannot control for confounding variables
Ways to control for potential confounding variables
Multivariate analysis
Multiple regression is a statistical technique based on correlation coefficients among variables
Take more than 2 measurements per individual
Case Study Research
Focus on a single subject
In-depth
Informative and valuable in combination with experiments
Downfalls of Case Study Research
Cannot generalize
Cannot establish cause-effect
Descriptive and Quasi-experimental findings in combination with experimental findings
Valuable
Additional “real” experiments can establish cause and effect
Validity of Biopsychological Claims
We need to think critically about claims
Scientific inference based off empirical observations to piece together unobservable phenomena
Need to consider: Is this peer-reviewed? Is it pseudoscience?
Main Premise of Evolutionary Psychology
Neural circuits evolved over natural selection
- some adapted unconsciously
- solve complex problems
- adaptive to reproduction and survival
Analogous Traits
Results from convergent evolution
-similar solutions to same environmental problems
Homologous Traits
Came from the same origin
Brain Expansion over Human Evolution
Rapid
Increased brain size in humans suggests increased brain size offers fitness advantages
Neocortex and other regions showed growth
Does Brain Size Determine our Intelligence?
Brain size does not equal IQ
Relative brain size is the best predictor of intelligence in primates
-the best way to show investment in cognition
Best Wa to Predict Intelligence based on Brain Structure
Relative cerebrum to brain stem best prediction of intelligence
-increase in cerebellum and cerebrum size and convolutions
What determines our traits?
A mixture of nature (genetics) and nurture (environment)
Heterochromatin
Blocked from transcription
Euchromatin
Open to transcription
Epigenetics
Regulation of gene expression by experience
How much DNA encodes genes?
only 1%
The rest are non-coding RNA (regulatory coding)
Regulatory sequences for expression/repression of genes
Epigenetic Control of Gene Expression by Modifications to DNA or Histone
Methylation of DNA and histones
Histone acetylation
Methylation of DNA and Histones
Causes nucleosomes to pack tightly together
Transcription factors cannot bind the DNA and genes are not expressed
Histone Acetylation
Results in loose packing of nucleosomes
Transcription factors can bind the DNA and genes are expressed
Gene-environment regulates methylation and histone acetylation (how?)
Lifestyle -exercise/diet Can be transgenerational -stress -alcohol consumption
Epigenetics in Gene Studies
Epigenetic changes are a byproduct of experience and not genetics
Genetically identical twins are not epigenetically identical
-similar in early life and diverge with age
-depending on tissue type
-monozygotic twins are not genetically identical
