Biological Psychology: Genes, Behavior, and Epigenetics

Introduction to Biological Psychology

• Biological psychology studies mental processes and behavior using biological principles.
• It explores both the differences and similarities in human behaviors.

Nature vs. Nurture

• It is a debate that questions whether behavioral traits originate from biology or environment.
• Both biological and environmental factors contribute to behavior.

Behavioral Genetics

• It studies how genes and the environment influence individual behavior and traits, including brain function.
• It focuses on the genetic basis of individual differences in how we think and act.
• Heredity and environment constantly interact to shape psychological and physical traits.

Epigenetics

• Study of heritable changes in gene expression without alterations to the DNA sequence.
• It aims to understand how genes influence behavior and mental processes.
• It focuses on how the environment affects genes and their expression through biological mechanisms.

Behavioral Genomics

• It studies DNA, inherited traits, and the relationship between specific genes and behavior.
• It shifts focus from individual genes to the entire genome, which is an organism’s complete set of genes.
• Also studies interaction between genes and environmental factors that influence human behavior.
• Twin and adoption studies are used to calculate heritability.
• Heritability is a measure of variability in behavioral traits among individuals accounted for by genetic factors.
• Heritability coefficient is a statistic between zero and one representing the degree to which genetic differences contribute to individual differences in a trait within a population.

Evolutionary Psychology

• Focuses on the evolutionary mechanisms that explain commonalities aiding survival and reproductive success.
• It emphasizes the evolutionary mechanisms at work in the similarities of human behavior, including cognition, emotion, development, and social practice.
• It interprets modern human behavior based on how brains and behaviors were shaped by ancestral environments.

Influence of Charles Darwin

• His theories have a profound impact on evolutionary psychology
• Natural Selection allows species to adapt, find resources, and mate to pass on favorable genetic traits.
• Evolution through natural selection requires heritable traits and reproductive advantage.
• Evolutionarily useful behaviors have had a beneficial function in our species cognitive development.
• The brain has cognitive adaptations for solving problems related to survival and reproductive fitness.
• Individuals with advantageous traits are more likely to survive and pass those genes on.

Sexual Selection Theory

• Certain traits evolve to increase chances of mating and passing on genes,
• Intrasexual selection is when the same-sex competes for access to the other sex,
• Intersexual selection is the influence of physical factors indicating reproductive health and fitness, as well as cultural factors that indicate social security.

Sexual Strategies Theory

• It defines the range of mating strategies humans pursue.
• Considers the challenges men and women face when pursuing these strategies.
• Includes the evolved solutions to these mating problems.
• Sexual overperception bias suggests men often misinterpret sexual interest from women.
• Evolutionary research on attraction highlights the importance of facial symmetry for mate selection.

Sociobiology

• Evolution has given us a genetic tendency to act to maximize the chances of passing on our genes.
• Psychological traits are thought to be selected to aid individuals in propagating their genes.

Hunter-Gatherer Theory

• It suggests that labor was divided based on sex as a means of survival.
• Males hunted, and females gathered because of physical and behavioral skills that are reproductively fit to the environment.

Biopsychosocial Theory

• Biology (genes), psychological components (thoughts, personality, mood), and social conditions (family support, stress, culture) are all considered to understand human behaviour.

Evolutionary Perspective

• Cognitive structures are designed by natural selection to aid survival and reproduction.
• Functions like hearing, smell, vision, pain, and motor control are examined as functions of the nervous system involved in survival and reproduction through thousands of generations.

Explore the principles of biological psychology and its study of mental processes and behavior through biology. Learn about nature vs. nurture, behavioral genetics, and epigenetics and their influence on behavior and traits.