Biological Basis of Psychology

Biological Basis of Psychology

• Psychology is the scientific study of the mind and behavior, with biology providing the fundamental understanding of the physical mechanisms underlying these processes.
• The brain, composed of neurons, is the primary organ involved in psychological functions.
• Neurons communicate through electrochemical signals, facilitated by neurotransmitters that carry messages across synapses.
• Specialized brain regions contribute to various cognitive and behavioral aspects; the cerebral cortex is crucial for higher-level cognitive functions like language and reasoning.
• Hormones, chemical messengers in the bloodstream, influence behavior and emotions, alongside the endocrine system.
• Genetics influence individual differences in psychological traits, with inherited genes contributing to predispositions for specific psychological disorders, though environmental factors are also vital.
• Evolutionary psychology explores how evolutionary pressures have shaped psychological traits, behaviors, and cognitive processes, suggesting many traits evolved to address adaptive problems faced by ancestors.

Brain Structure and Function

• Distinct brain regions have specialized functions, including the cerebrum, cerebellum, and brainstem.
• The cerebrum is responsible for higher-level cognition, sensory perception, and voluntary movement.
• The cerebellum coordinates movement and balance.
• The brainstem controls essential body functions such as breathing and heart rate.
• Various brain areas regulate distinct sensory and motor activities; the visual cortex processes visual information.
• Neuroimaging techniques like fMRI (functional magnetic resonance imaging) and PET (positron emission tomography) allow real-time study of brain activity.

Neurotransmitters and Hormones

• Neurotransmitters are chemical messengers that transmit signals across synapses between neurons.
• Common neurotransmitters include dopamine, serotonin, norepinephrine, and GABA, each influencing behavior, mood, and cognition differently.
• Hormones are chemical messengers secreted by endocrine glands.
• Hormones like testosterone and estrogen influence sexual development and behavior, while stress hormones like cortisol activate the "fight or flight" response.
• Neurotransmitters and hormones interact to produce complex behaviors and mental states.

Genetics and Behavior

• Genes, units of hereditary information, provide the blueprint for building and maintaining an organism.
• Genes contribute to individual differences in psychological traits, but environmental influences also significantly shape these differences.
• Polygenic inheritance implies multiple genes influence a single trait.
• Gene-environment interactions determine how genetically predisposed individuals express or restrain certain traits.
• Genetic predispositions can increase the likelihood of developing specific psychological disorders, like depression or schizophrenia.

Evolutionary Psychology

• Evolutionary psychology examines how natural selection has shaped psychological traits and behaviors.
• Psychological characteristics, such as problem-solving abilities, have adaptive value.
• Some evolutionary perspectives suggest psychological mechanisms like mate selection strategies are evolved responses to ancestral challenges.
• The evolutionary approach helps understand human behavior's universality and diversity across cultures and environments. Addressing questions about the origins and functions of psychological traits.

Biological Influences on Psychological Disorders

• Biological factors, including genes, brain structure/function, and neurotransmitter imbalances, influence psychological disorder development.
• Diseases like Alzheimer's and Parkinson's are linked to specific brain structural and chemical changes.
• Various mental disorders, such as depression and anxiety, may have biological roots, potentially involving imbalances in neurotransmitter systems.
• Genetic predispositions heighten the risk of certain disorders, highlighting the complex interplay between genes and environment.
• Treatments for psychological disorders can involve medications targeting specific biological systems.