Chapter 2 Neuroscience and Behavior PDF

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Neuroscience and Behavior...

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Neuroscience & Behavior

Biological Basis of Behavior   

Your every idea, every mood, every urge is a biological occurrence It is your brain that enables your mind Neuropsychologists and psychologists working in neuroscience are concerned with the links between biology and behavior

Neural Communication Body’s information system is built from billions of interconnected cells called Neurons Neuron A nerve cell consisting of different parts Consists of:

 Synapse o All the space surrounding the neuron  Cell body o The cell’s life support  Dendrites o Receive messages from other cells  Axon o Passes messages away from the cell body to other neurons, muscles, or glands  Neural Impulse (Action Potential) o A brief electrical charge that travels down an axon and is generated by the movement of positively charged atoms in and out of channels in the axon’s membrane  Myelin Sheath o Covers the axon of some neurons and helps speed up messages through the neuron  Terminal branches of axon o Branches endings of an exon that transmit messages to other neurons Types of Neurons

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Sensory Neurons o Carry messages from the body’s tissues and sensory organs to the brain and spinal cord Motor Neurons o Carry messages and instructions from brain and spinal cord to bodily tissues Interneurons o Brain’s internal communication system

Neurotransmitters Chemicals that:   

Are released from the sending neuron and travel across the synapse Then they bind receptor sites on the receiving neuron, thereby influencing it to trigger or inhibit an action potential

Examples: o Serotonin  Affects mood, hunger, sleep, and arousal  Undersupply can lead to depression o Norepinephrine  Helps control alertness and arousal  Undersupply can lead to depression

The Nervous System Nervous System Consists of all the nerve cells. It is the body’s speedy, electrochemical communication system Central Nervous System (CNS) The brain and spinal cord Peripheral Nervous System (PNS) The sensory and moto neurons that connect the central nervous system to the rest of the body

The Cerebral Cortex  

The body’s ultimate control and information-processing center Divided into two hemispheres (Left and Right) o Each hemisphere controls the opposite side of the body o Motor functions exercise

Structure of the Cortex Each brain hemisphere is divided into four lobes that are separated by prominent fissures 1) Frontal lobe (Forehead) a. Conscious thought, executive processing, higher order functions 2) Parietal Lobe (Top to Rear Head) a. Visual-spatial processing, sensory integration 3) Occipital Lobe (Back Head) a. Sense of sight; location of visual cortex 4) Temporal Lobe (Side of Head) a. Sense of hearing; location of auditory cortex Functions of the Cortex Motor Cortex The area at the rear of the frontal lobes that control voluntary movements Sensory Cortex (Parietal Cortex) Receives information from skin surface and sensory organs Right-Left Differences 

The myth of Right-brained vs Left-Brained o States that left-brained individuals are more logical, methodical, and analytical, while right-brained individuals are more creative and artistic o Each of the hemispheres perform distinct functions, but we use our whole brains  Right hemisphere = Perceptual tasks  Left hemisphere = Speaking, Calculations

Viewing inside the Brain     

EEG (electroencephalogram) o Records brain waves PET (Positron emission tomography) o Depicts brain activity by showing brain area’s consumption of glucose (its chemical fuel) MRI (Magnetic resonance imaging) o Uses magnets to provide a detailed picture of soft tissues Functional MRI o Illustrates blood flow in the brain as people perform certain mental activities Using fMRI to predict behavior...