Download Biological and Psychology Why are psychologists concerned about

Biological and Psychology
Why are psychologists concerned about human biology?
 The nervous system and body chemistry play a vital role in our behavior and mental
processes
 Many of the important questions that psychologists ask are related to biology and the
brain
 Questions
o Are the two halves of the brain specialized to perform different functions?
o How do mood altering drugs work?
o What happens inside the body when you feel a strong emotion?
o Are some mental disorders the result of chemical imbalances in the brain?
Biological Psychology - Branch of psychology concerned with the links between biology and
behavior
Some biological psychologists call themselves behavioral neuroscientists, neuropsychologists,
behavior geneticists, physiological psychologists, or biopsychologists
Key: Understanding Neurons and the Nervous system
The Nervous System
 the body’s speedy, electrochemical communication system
 consists of all the nerve cells of the peripheral and central nervous systems
 Billions of interconnected cells
The Nervous System: Divisions
o Central nervous system (CNS) - Brain and spinal cord
o Peripheral nervous system (PNS)
o Somatic nervous system - Sensory nerves and muscular activity
o Autonomic nervous system – internal organs
 Sympathetic nervous system – arouses
 Parasympathetic nervous system – calms
The Nervous System: Pathways
 Interneurons – neurons of the spinal cord and brain which process information
 Afferent Nerves (sensory nerves) - Carry information to the spinal cord and brain
 Efferent Nerves (motor nerves) - Carry information to the muscles
Neurons are individual cells in the nervous system that receive, integrate, and transmit
information.
 Approximately 100 billion neurons and 10 trillion connections
 Speeds up to 330 miles per hour
 Glia Cells: Provide support and nutrition
 Over 200 types of neurons and glia cells
Common Features of Neurons
 Dendrites
 Cell body or soma
 Axon
 Myelin sheath
 Terminal buttons
Synapse - a junction between the axon tip of the sending neuron and the dendrite or cell body
of the receiving neuron. This tiny gap is called the synaptic gap or cleft.
Neurotransmitters – chemicals that transmit information from one neuron to another.
 Stored in small sacs within the terminal buttons
 Nerve impulse triggers their release
 Over 50 have been identified
 Major ones are described in the text
Drugs and Neurotransmitters
 Agonist – mimics or enhances NT effects
 Antagonist – blocks effects of NT
Brain and its Structures
Brain: 3 Main divisions
 Hindbrain – vital functions – medulla, pons, and cerebellum
 Midbrain – sensory functions –reticular activating system
 Forebrain – emotion, complex thought – thalamus, hypothalamus, limbic system,
cerebrum, cerebral cortex
Hindbrain - Most primitive part of the brain – basic life sustaining functions
 Brain Stem - Alertness, breathing, heart rate, blood pressure
 Medulla – control breathing, regulate reflexes
 Cerebellum – movement, motor coordination
 Pons – governs sleep and arousal
Midbrain
Relay between hindbrain and forebrain
Integrating sensory info.
Reticular Formation - Regulates arousal, attention, sleep/wakefulness, pain perception
Forebrain - Largest and most complex regions of the brain
(Thalamus, hypothalamus, limbic system, cerebrum, or cerebral cortex)
Thalamus - Relay station for much sensory information
Hypothalamus - Eating, drinking, sexual behaviors
It directs several maintenance activities like eating, drinking, body temperature, and control of
emotions.
It helps govern the endocrine system via the pituitary gland.
Limbic System – memory, motivation and emotions
 Amygdala - Emotional awareness and expression
 Hippocampus - Formation and storage of memories
Damage to the Hippocampus – The case of Clive Wearing
Forebrain: Cerebrum
Largest and most complex part of the brain
The cerebral cortex is the convoluted outer layer of the cerebrum
Cerebral Cortex
 Occipital Lobe – Vision
 Temporal Lobe – Hearing, language processing, memory
 Frontal Lobe – Intelligence, personality, voluntary muscles
 Parietal Lobe - Spatial location, attention, motor control
Functions of the Cortex
 The Motor Cortex is the area at the rear of the frontal lobes that control voluntary
movements.
 The Sensory Cortex (parietal cortex) receives information from skin surface and sense
organs.
Association Cortex - Region of the cortex in which the highest intellectual functions occur
75% of the cortex
Damage does not lead to specific loss of function
e.g., Phineas Gage Video
More intelligent animals have increased “uncommitted” or association areas of the cortex.