PSYCHOLOGY BIOLOGY
Truth or fiction? Individual cells in the human body can be several feet long. All behavior is governed by whether a neuron, the basic cell of the nervous system, is activated (fires). Neurons never actually touch one another. Strong emotions, like anger, result from more intense firing of neurons.
Truth or fiction? Drugs work either to mimic or mask one of the body’s naturally occurring chemicals, called neurotransmitters.
Neural vs. Road Network
Neuron
Anatomy of a Neuron Neuron-nerve cells that run through our entire bodies and are responsible for sending and receiving messages Soma-cell body produces energy and keeps it healthy Dendrites-receive information from other neurons; pass messages through the cell body
Anatomy of a Neuron Axon-carries messages away; vary in size Myelin-white fatty substance that insulates and protects the axon; helps speed up the transmission of the message Axon terminals-small fibers which branch out from axon Synapse-Serves as a junction between the axon terminals of one neuron and the dendrites of another neuron Neurotransmitters-chemicals stored in sacs in the axon terminals
Sensory-Messages to the central nervous system Afferent-Sensory Types of Neuron Sensory-Messages to the central nervous system Afferent-Sensory Motor-Messages that leave the central nervous system and go to the muscles/glands Efferent-Motor
Neuron Firing-Toilet (Tiny Electrical Charge)
Neural Communication (Action Potential)
Neural Communication (Refractory Period)
Neural Communication (Resting Potential)
What part of the body is responsible for all of these tasks?
Child’s Brain (2 lbs.)
Human Brain (3 -4 lbs)
How does the brain gain weight? (Dendrites) Your brain is a thinking organ that learns and grows by interacting with the world through perception and action. The human brain is able to continually adapt and rewire itself.
What does the brain do? Regulates all human physiological, behavorial, and emotional functions Brain regulates breathing even though we credit our lungs for this process Brain regulates heartbeat
Ways to Investigate the Brain Watching a person’s behavior Electrical shock PET (positron emission tomography) Scans MRI Using animals
http://science. education. nih http://science.education.nih.gov/supplements/nih2/addiction/activities/activities_toc.htm
PET Images
Lower-Level (Central Core/Brainstem) (A & B on Handout) automatic survival functions Pons – control dreaming and sleep Thalamus – directs messages/switchboard Medulla – heartbeat/breathing Reticular Formation – wakefulness/arousal Cerebellum – little brain responsible for balance http://www.learner.org/discoveringpsychology/brain/brain_flash.html
The Limbic System (C on Handout) (regulatory of various function) Hippocampus – process new memories for storage Amygdala – emotions (fear/anger) Hypothalamus – controls eating, drinking, and body temperature
Cerebral Cortex (Higher cognitive and emotion functions) (D on Handout) Longitudinal Fissure – separates the right and left hemisphere (crevice) Corpus Callosom – neural fibers (tissue) connecting the two hemispheres and responsible for carrying messages Frontal Lobes – making plans and judgments Parietal Lobes – processing information Occipital Lobes – visual processing Temporal Lobes – auditory (hearing) areas
Motor Cortex Strip of tissue Rear of frontal lobe Body movement Cross-wired Right hemisphere = left body Left hemisphere = right body
Somatosensory Cortex Front of parietal lobe Connected to motor cortex Body sensations Left hemisphere = stub right toe Right hemisphere = burn left hand
Language Abilities Two key language areas within the hemisphere responsible for language functions; usually left hemisphere Wernicke’s area – role in language comprehension; might be able to speak but their speech is often meaningless Broca’s area – frontal lobe and motor cortex controls facial expression; use simple sentences and speak slowly “speech bound by chains”
Left vs. Right Hemispheres Hemispheres do not act independently of one another even though each is capable of functioning by itself Left – Language Right – Spatial and connections between words
Left vs. Right Brained
Left vs. Right Brained Logical Sequential Rational Analytical Objective Looks at parts Random Intuitive Holistic Synthesizing Subjective Looks at wholes
Brain Plasticity Most likely in children Remove one hemisphere of the brain; fills up with cerebrospinal fluid Neurons in one hemisphere are able to make new connections and take over many of the new functions that was once performed by the other hemisphere