Psychology

• Biological psychology


  The scientific study of the biological bases of behavior and mental states
• Biological psychology


  • Focuses on the nervous system, endocrine system and genetics
  • Examines thoughts, feelings, and behaviors from a biological and physical point of view

  
• All that is psychological is first physiological. All thoughts, feeling & behavior ultimately have a biological cause
• Importance of biological psychology

  • Comparative method
  • Physiology
  • Investigation of inheritance
• Comparative method


  Different species of animal can be studied and compared to help understand human behavior
• Physiology


  How the nervous system and hormones work, how the brain functions, how changes in structure and/or function can affect behavior

  
• Investigation of inheritance


  What an animal inherits from its parents, mechanisms of inheritance (genetics)
• Nature


  What is innate and is influenced by genetic inheritance and other biological factors
• Nurture


  The influence of external factors after conception, e.g., the product of exposure, life experiences and learning on an individual
• Most psychological researchers are interested in investigating how nature and nurture interact in a host of qualitatively different ways
• Nativism


  The extreme hereditary position that psychological characteristics are "wired in" before we are even born
• Empiricism


  The extreme nurture position that at birth the human mind is a blank slate and psychological characteristics are the results of learning
• History of biological psychology

  • Early philosophers debated the mind/body phenomenon
  • Scientific researchers became interested in understanding how different parts of the brain control human behavior
  • Only recently have scientists recognized the central role of the brain in controlling behavior
• Darwin's theory of evolution through natural selection is central to all modern biology and psychology
• The brain was not considered an asset when the Egyptian pharaoh, Tutankhamen, was mummified
• Aristotle considered the brain to be only a cooling unit to lower the temperature of the hot blood from the heart
• Hippocrates wrote that the brain was the seat of intellect
• Herophilus advanced knowledge of the nervous system by dissecting bodies and tracing spinal nerves
• Galen provided interesting drawings of the brain and advanced the idea of animal spirits
• Leonardo da Vinci studied the workings of the human body and laid the foundations of anatomical drawings
• Rene Descartes proposed the concept of spinal reflexes and a neural pathway for them, and the notion of dualism
• The 19th century saw the concept of localization of function arise, and the development of phrenology
• Paul Broca supported the view that language and brain are related
• William James signaled the beginnings of a modern biological psychology
• Ebbinghaus and Thorndike showed how to measure learning and memory
• Pavlov did research on the conditioned reflex in animals
• Lashley focused on assessing the behavioural effects of brain lesions

  
• Hebb showed how complex cognitive behavior could be accomplished by networks of active neurons
• Contemporary research involves National Data Banks and brain mapping
• Lesions


  Brain damage from strokes, falls, accidents, etc. that provide a picture of what is missing as a result

  
• Psychologists sometimes intentionally create lesions in animals to study the effects on their behaviour
• Lesions


  Brain damage from strokes, falls, accidents, etc. that provide a picture of what is missing

  
• Lesions may be created intentionally through surgery to remove tumours or reduce epilepsy effects
• Psychologists sometimes intentionally create lesions in animals to study effects on behaviour
• Lesions allow observation of loss of brain function, e.g. vision, language, speech affected by stroke
• Phineas Gage


  Railroad worker who had frontal lobe damage from an iron rod, resulting in personality changes
• Studies concluded frontal lobe is involved in moral judgment, and lesions there make people more likely to agree to do harm
• Electrical activity recording


  Placing detectors in brain to study neuron responses, primarily used with animals
• Electroencephalography (EEG)


  Technique that records electrical activity of brain's neurons through electrodes on head

  
• EEG can show sleep, wakefulness, brain abnormalities like epilepsy, and track brain activity during tasks