Psychology Chapter 3 Notes PDF

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Chapter 3 notes. Professor Sameul Van Buskirk...

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Psychology Chapter 3 Biological psychology: Nerve cells   

Neurons o Never cells specialized for communication with each other 85 million neurons, 160 trillion connections between them Parts of a neuron o Cell body (soma)  Center of neuron, builds new cell components o Dendrites  Branch-like extensions for receiving information from other neurons o Axon  Portion of neuron that sends signals  Synaptic vesicle  Spherical sac containing neurotransmitters  Neurotransmitters  Chemical messengers specialized for communication from neuron to neuron o Synapses  Tiny fluid filled spaces between neurons through which neurotransmitters travels  Synaptic clef  A gap into which neurotransmitters are released from the axon terminal

Glial cells  

Play roll in the formation of myelin and the blood-brain barrier, responds to injury, removes debris, and enhances learning and memory Types of Glial cells o Astrocytes- most abundant, increase accuracy of transmission, help control blood flow in the brain, plays vital role in the development of the embryo, memory, thought, and the immune system. o Oligodendrocytes- promote connections and produce the myelin sheath

Electrifying thought  

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Neurons respond to neurotransmitters by generating electrical activity Resting potential o Electrical charge difference (-60 millivolts) across the neuronal membrane, when the neuron is not being stimulated or inhibited Threshold o Membrane potential necessary to trigger an action potential

Action Potentials 

Action potential

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Electrical impulse that travels down the axon triggering the release of neurotransmitters

The absolute refractory period   

Neurons can fire 100-1000 times per second When released, the neurotransmitters bind with the next neurons receptor site Absolute refractory periodo Time during which another action potential is impossible; limits firing rate

Chemical communication: Neurotransmission      

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This process is halted by reuptake, when neurotransmitters go back into the axon terminal Some neurotransmitters excited and some inhibit Glutamate and GABA are the most common neurotransmitters in the central nervous system Glutamate is excitatory, GABA is inhibiting Acetocholine influences arousal, selective attention, sleep, and memory Monoamines contain only one amino acid o Norepinephrine and serotonin influence arousal o Dopamine plays a role in our response to rewarding experiences Neuropeptides have specialized functions (like endorphins for pain relief) Anandamines bind to the same receptors as THC and influence eating, motivation, memory, and sleep

Psychoactive drugs   

Psychoactive drugs impact mood, arousal, or behavior by acting as agonists or antagonists for neurotransmitters Agonists- Increase neurotransmitter activity Antagonists- Decrease neurotransmitter activity

Agonists and Antagonists 

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Agonists o Opiods- mimic endorphins o Alcohol, Xanax- stimulate GABA receptors o Prozac, Paxil- block serotonin reuptake Antagonists o Antipsychotics- block dopamine from receptors o Botox- blocks Acetocholine

Neural plasticity  

Plasticity- nervous system’s ability to change over time Neurons change in four ways during development 1. Growth of dendrites and axons 2. Synaptogenesis 3. Pruning 4. Myelination

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During learning, long-term potentiation occurs and makes synapses perform better There is only limited recovery following brain injury or serious illness Stem cell therapies may someday encourage plasticity after injury or degeneration Neurogenesis- creation of new neurons- does not occur during adulthood

The brain-behavior network  

Sensory information comes into-and decisions come out of- the central nervous system (CNS) The nerves outside the CNS are called the peripheral nervous system (PNS)

The central nervous system 

The CNS is divided into distinct systems based on located and function

Cerebral cortex    

The forebrain is the most developed area of the human brain, giving us our advanced intellectual abilities Consists of two cerebral hemispheres connected by the corpus callosum which allows communication between them The majority of the forebrain is composed of the cerebral cortex It can be divided into four lobes, each associated with a different function

Frontal Lobe   

Oversee and organize most other brain functions (executive functioning) The body is mapped onto the motor cortex The prefrontal cortex is responsible for thinking, planning, and language o Broca’s area important for speech comprehension

Parietal lobe   

Contains the somatosensory cortex, which is sensitive to touch, pain, and temperature Helps track objects locations in space Communicates information to the motor cortex every time we reach, grasp, or move our eyes

Temporal lobe  

The lower part of the cerebral cortex, it plays a role in hearing, understanding language, and storing autobiographical memories Contains the auditory cortex and Wernicke’s area responsible for speech comprehension

Occipital lobe  

Lies at the rear of the brain and is specialized for vision When sensory information enters the brain, it first goes to that sense’s primary sensory cortex, then to the associated cortex

Basil Ganglia 

Forebrain structure that helps control movement

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Allows us to perform movements to obtain rewards and reinforcement Damage can contribute to Parkinson’s disease

Limbic system     

The emotional center of the brain that also has a role in smell, motivation, and memory Thalamus relays information from the sensory organs to the primary sensory cortex Hypothalamus regulates and controls internal body stats; controls the pituitary gland Amygdala plays key roles in fear, excitement, and arousal Hippocampus plays a role in spatial memory; damage causes inability to form new memories

Brain stem     

Connects the cerebral cortex and spinal cord Performs some basic bodily functions Serves as a relay station between the cortex and the rest of the nervous system Midbrain contributes to movement, tracking of visual stimuli, and reflexes triggered by sound Reticular activating system connects the forebrain and cerebral cortex and plays key role in arousal

Hindbrain   

Cerebellum plays a predominant role in our sense of balance and enables us to coordinate movement and learn motor skills Pons connects cortex to cerebellum and triggers dreams Medulla regulates breathing, heartbeat, and other vital functions

Spinal cord   

Thick bundle of nerves that conveys signals between the brain and the body Sensory nerves carry information from the body to the brain; motor nerves carry information from brain to the rest of the body Also contains interneurons, which allow reflexes to happen

Peripheral nervous system  

Somatic nervous system conveys information between the CNS and the body, controlling and coordinating voluntary movement Autonomic nervous system controls the involuntary actions, internal organs, and glands o Has two divisions, sympathetic and parasympathetic...