Neuroscience

Definitions:

neuron – cells in the nervous system that communicate with one another to perform information processing tasks

cell body – the part of the neuron that coordinates information-processing tasks and keeps the cell alive

dendrite – the part of the neuron that receives information from other neurons and sends it into the cell body

axon – the part of the neuron that transmits information to other neurons, muscles or glands

myelin sheath – an insulating layer on the neurons

association areas – areas of the cerebral cortex that are composed of neurons that help provide sense and meaning to information registered in the cortex

glial cell – the support cells found in the nervous system

synapse – junction region between the axon of one neuron and the dendrite or cell body of another

afferent neuron – neurons that conduct impulses inwards to the brain or spinal cord

efferent neuron – neurons that conduct impulses outward from the brain and spinal cord

interneuron – neurons that connect to motor neurons, sensory neurons and other inter neurons

action potential – an electric signal that is conducted along an axon to a synapse


neurotransmitter – chemicals that are transmit information across the synapse to the dendrites of the receiving neurons

hormone – chemical substances that are produced in the endocrine system and then are transported in the blood to certain tissues, for specific functions

central nervous system – the nervous system composed of the brain and spinal cord

peripheral nervous system – the nervous system that connects the central nervous system to the body, organs and muscles

autonomic nervous system – the set of nerves that carry involuntary and automatic commands that control blood vessels, body organs, and glands

sympathetic nervous system – the nerves that prepares the body for action in a threatening situation

parasympathetic nervous system – nerves that help the body return to a normal resting state

brain stem – a portion of the brain that continues with the spinal cord and comprises of the medulla, pons, midbrain, and parts of the hypothalamus, functioning in the control of reflexes, internal respirations and heart beat

medulla – the extension of the spinal cord into the skull that coordinates heart rate, circulation, and respiration

RAF - the reticular activating formation is a brain structure that regulates sleep, wakefulness, and levels of arousal

cerebellum – a large structure of the hind brain that controls fine motor skills

pons – the brain structure that sends information from the cerebellum to the rest of the brain

cerebral cortex – the outermost layer of the brain, visible to the naked eye and is divided into two hemispheres 

thalamus – subcortical structure that sends and filters information from the senses and transmits the information to the cerebral cortex

hypothalamus – a structure that regulates body temperature, hunger, thirst, and sexual behaviour

limbic system – group of the forebrain structures including the hypothalamus, amygdala, and hippocampus, which are involved in motivation, emotion, learning, and memory

hippocampus – a critical structure for creating new memories and integrating them into a network of knowledge so that they can be stored indefinitely in other parts of the cerebral cortex

amygdala - part of the limbic system that has a central role in many emotion processes, particularly the formation of emotional memories 

basal ganglia – a set of structures that directs intentional movements

corpus callosum – thick band of nerve fibres that connect the large areas of the cerebral cortex on each side of the brain and supports communication of information across the hemispheres

occipital, parietal, temporal, and frontal lobes – these lobes of the cerebral cortex are primarily related with visuals, information processing and touch, hearing and language, movement, abstract thinking, planning, memory, and judgment

Learning Objectives:

Identify different functions of the nervous system

• convey chemical information throughout the body
• contains the central and peripheral which carry out different functions within the body

Identify structure and function of different parts of the neuron

• dendrite - receives information from other neurons and sends it into the cell body
• cell body - coordinates information-processing tasks and keeps the cell alive
• axons - transmits information to other neurons, muscles, or glands

Compare/contrast the different classes of neurons

• sensory neurons - takes information from the external forces and sends it to the spinal cord
• motor neurons - carry information from the spinal cord to the muscles to produce movement
• interneuron - connect sensory neurons to motor neurons and other interneurons

Compare/contrast electrical versus chemical stimulation of a nerve

• electrical impulses send electrical currents
• chemical stimulus - chemicals are secreted into the synapse to be picked up by dendrites for the neuron to send the information

Describe how excitatory and inhibitory processes work in transmission across the synapse

• excitatory starts the transmission and inhibitory stops it

Compare/contrast different classes of neurotransmitters

• all the neurotransmitters are found on table 3.1 in the textbook on page 83

Recognize the relative importance of different brain regions and structures for sustaining life, for human functioning, and for human cognition

• the different brain regions help us categorize the information and help us carry out different functions throughout or bodies

Describe empirical evidence for asymmetry in language function

• thanks to split-brain patients, the left hemisphere is more dominant to verbalize given knowledge; in example, one can say they saw Leonardo DiCaprio when his face is shown to their right visual field
• looking at patients with Broca's aphasia, we can conclude that Broca's area in the left hemisphere is responsible for the planning of language
• looking at patients with Wernicke's aphasia, we can conclude that Wernicke's area, also in the left hemisphere, is responsible for the understanding of language

Diagram routes for vision, audition, language, and motor control within the central nervous system

• Vision  -optic nerve -thalamus -occipital lobe
• Audition -hair cells -thalamus -temporal lobes -Wernicke's area -frontal lobes
• Language -Broca's area -frontal lobes -midbrain -motor neurons
• Motor -motor area -midbrain -motor neurons

Identify the location and function of brainstem, medula oblongata, thalamus, reticular activating formation, cerebellum, basal ganglia, amygdala, hippocampus, hypothalamus, the four lobes of the cerebral cortex, and the corpus callosum

• the functions are within the definitions

Compare/contrast the damage and loss of function accompanying Broca's and Wernicke's aphasia

• Wernicke's aphasia – lack of understanding language
• Broca’s aphasia- inability to plan sensible language

Identify asymmetries in the function of the cerebral hemispheres and how this relates to language 

• looking at language specifically, the left cerebral hemisphere is where information is consolidated, and language is planned

Predict deficits in function that arise from severing the corpus callosum

• a split-brain patient will not be able to verbalize and point to the correct image if two different images are shown to a certain visual field

Thought Question:

Which part of the brain is the most important? In your discussion, decide on what "important" means and develop a good argument for the part that you select as most important.

All parts of the brain are important. Without the hindbrain, we are unable to live; without the midbrain, we are unable to live on as a species; without the forebrain, we are unable to appreciate life as we know it; in fact, we would not have come so far as a technologically-advanced society without the forebrain.