380 likes | 671 Vues
Chapter 2. The Biology of Mind. Neurons and Neuronal Communication: The Structure of a Neuron. There are billions of neurons (nerve cells) throughout the body. Action potential: a neural impulse that travels down an axon like a wave. The Synapse. Neural Communication:.
E N D
Chapter 2 The Biology of Mind
Neurons and Neuronal Communication:The Structure of a Neuron There are billions of neurons (nerve cells) throughout the body.
Action potential:a neural impulse that travels down an axon like a wave
Dopamine pathways Serotonin pathways Networks of neurons that communicate with dopamine are involved in focusing attention and controlling movement. Networks of neurons that communicate with serotonin help regulate mood.
Agonist and AntagonistMolecules An antagonist molecule fills the lock so that the neurotransmitter cannot get in and activate the receptor site. An agonistmolecule fills the receptor site and activates it, acting like the neurotransmitter.
Central & Peripheral Nervous Systems The central nervous system [CNS] The peripheral nervous system [PNS]
Neural Networks These complex webs of interconnected neurons form with experience. Remember: “Neurons that fire together, wire together.”
Interneurons in the Spine Reflexes
The Endocrine System (The “Master Gland”)
Studying cases of brain damage When a stroke or injury damages part of the brain, we have a chance to see the impact on the mind. Phineas Gage
Monitoring activity in the brain EEG: electroencephalogram PET: positron emission tomography MRI: magnetic resonance imaging fMRI: functional MRI
Functional Magnetic Imaging This fMRI scan shows increased activity in the visual cortex when a person looks at a photograph.
The Hypothalamus Thalamus
The Cerebral Cortex The brain has left and right hemispheres
The Motor and Sensory Strips Axons sending motor signals to the body Axons sending sensory information to the cortex
Frontal Lobes The frontal lobes are active when we move and in the processing of new memories. The prefrontal cortex are active in “executive functions” such as judgment, planning, and inhibition of emotions and impulses. Prefrontal Cortex
Parietal Lobe Association Areas This part of the brain has many functions in the association areas behind the sensory strip: • performing spatial and mathematical reasoning • monitoring the sensation of movement
Temporal Lobe Association Areas Some abilities managed by association areas in this “by the temples” lobe: • recognizing specific faces • managing sensory input related to sound, which helps the understanding of spoken words
Plasticity: The Brain is Flexible If the brain is damaged, especially in the general association areas of the cortex: • the brain does not repair damaged neurons, BUT it can restore some functions • it can form new connections, reassign existing networks, and insert new neurons, some of which grown from stem cells This 6-year-old had a hemispherectomy to end life-threatening seizures; her remaining hemisphere compensated for the damage.
The intact but lateralized brainRight-Left Hemisphere Differences Right Hemisphere Left Hemisphere Thoughts and logic Details such as “trees” Language: words and definitions Linear and literal Calculation Pieces and details Feelings and intuition Big picture such as “forest” Language: tone, inflection, context Inferences and associations Perception Wholes, including the self