06. Nervous System and Brain Pt. 1 L1-5 Flashcards
Ablation
the surgical removal, destruction or cutting of tissue
Axon
Long strand-like part of a neuron that conducts electrical impulses away from the cell body to the axon terminals of a neuron
Axon terminals
the ends of a neuron that release a message into the synapse
Brain versus heart debate
a historical debate surrounding whether the heart or the brain was responsible for thoughts, feelings, and behaviour
Computerised tomography (CT)
a STRUCTURAL neuroimaging technique that involves taking continuous two-dimensional x-ray images of a person’s brain or body in order to provide both two and three-dimensional images
Contralateral functions
the role of each cerebral hemisphere to receive sensory information from, and control the movement of, the opposite side of the body
Dendrites
the bushy spines of a neuron that receive a message
Dualism
in the mind-body problem, the view that the mind and the body are separate and distinguishable things
Electrical brain stimulation (EBS)
a research or therapeutic technique that involves electrically stimulating parts of the brain to then observe the relevant behavioural response
Functional magnetic resonance imaging (fMRI)
a FUNCTIONAL neuroimaging technique that uses magnetic and radio fields to take two and three-dimensional images of the brain and its activity levels. Detects changes in oxygen levels and blood to show brain function (higher uptake of oxygen indicates greater brain activity)
GABA (Gamma amino-butyric acid)
Inhibitory neurotransmitter: means it makes the post synaptic neuron less likely to fire an action potential. It slows neural transmission e.g reduces stress response
Glutamate
Glutamate is the major excitatory neurotransmitter in the brain. Makes post-synaptic neuron more likely to fire an action potential. Glutamate is therefore associated with Cognition, Memory, Learning, Behaviour, Movement
Hemispheric specialisation
the idea that each of the brain’s cerebral hemispheres has its own specialisations
Localisation of function
the psychological principle that suggests that different areas of the brain are responsible for different behaviours and mental processes
Lock and Key process
The distinct molecular structure of the neurotransmitter being matched by the receptor site means that the receptor site will only respond to specific neurotransmitters and ignore others.
Magnetic resonance imaging (MRI)
a neuroimaging technique that uses magnetic and radio fields to take two and three-dimensional images of the brain
Mind-body problem
a debate that questions whether our mind and body are separate and distinguishable things or whether they are the same thing
Monism
in the mind-body problem, the view that the mind and the body are one and the same thing
Motor messages
information about voluntary movement transmitted from the CNS to the skeletal muscles
Myelin
the fat and protein substance that surrounds and insulates the axon of a neuron
Myelination
the formation of myelin around the axons of neurons
Nervous system
the complex network of specialised cells in the body that allows the communication of information around the body about the internal and external environment
Neuroimaging
a range of techniques used to capture images of the brain’s structure, function and activities
Neuron
a nerve cell responsible for transmitting, receiving, and processing information
Neurotransmission
the process in which a neuron sends a message
Parasympathetic nervous system
a branch of the ANS responsible for returning and maintaining the body’s visceral organs, muscles and glands at optimal and balanced functioning
Peripheral nervous system (PNS)
all nerves outside the CNS, responsible for carrying information to and from the CNS
Phrenology
the study of the shape and size of the human skull to determine personality and mental functioning
Plasticity
the ability of the brain to physically change in response to experience and learning
Positron emission tomography (PET)
a neuroimaging technique that uses a scanning device to take coloured images of the brain, showing its functional activity and structure by tracing the levels of a radioactive substance in the brain
Postsynaptic neuron
the neuron that receives a message from the synapse
Presynaptic neuron
the neuron that releases a message into the synapse
Sensory messages
information about the body’s sensations transmitted from the PNS to the CNS
Sensory receptors
the receptors on a neuron that specialise in receiving information about specific kinds of sensory stimuli
Skeletal muscles
muscles connected to the skeleton that are involved in conscious, voluntary movement- utilised in the Somatic NS
Somatic nervous system (SNS)
the branch of the PNS responsible for sending motor information from the CNS to the body’s skeletal muscles, and bringing sensory information from the body to the CNS in order to formulate voluntary responses
Spinal cord
a long cable of nerve tissue connecting the brain to the peripheral nervous system, responsible for carrying motor information from the brain, and sensory information from the body
Sympathetic nervous system
a branch of the ANS responsible for activating the body’s visceral organs, muscles, and glands for increased activity or when under threat
Synapse
the area in which neurotransmission occurs between two neurons, **including the sending end of the presynaptic neuron, the gap between two neurons, and the receiving end of the postsynaptic neuron **
Synaptic gap
the space between two neurons into which a neuronal message is transmitted
Karl Lashley’s two key conclusions about the brain based on ablation studies:
Mass action: large areas of the brain function as a whole for complex functions (if part of brain is destroyed , loss of function will depend on amount of destroyed cortex)
Equipotentiality: healthy part of the cortex can take over the function of an injured part (plasticity)
Lobotomy
devised by Moniz
Involves scraping away (via the eye) most of the connections in the prefrontal cortex (the anterior part of the frontal lobes of the brain).
split-brain surgery
Split brain surgery involved cutting the band of nerve tissue (corpus callosum) connecting the two hemispheres.
Sperry and Gazzaniga split-brain studies: key findings
The left hemisphere is responsible for the organisation of language expression and comprehension, and when images/words are not processed in this hemisphere, they cannot be verbally stated.
This is because information processed in the right hemisphere (the image seen) could not be transferred as it would be in an intact brain, via the corpus callosum, to the left hemisphere for language processing.
Electroencephalograph (EEG)
DARE
Detects, amplifies and records general patterns of electrical activity within the brain
Central Nervous System (CNS)
The central nervous system (CNS) is composed of the brain and spinal cord. It processes sensory information to activate appropriate actions.
Autonomic NS (ANS) functions
The autonomic system is responsible for AUTOmatic responses.
It carries information to internal bodily structures (e.g., heart, lungs, glands) that carry out basic life functions.
Autonomic NS sub-divisions
Divided into three main systems: Sympathetic and Parasympathetic, and Enteric.
Physiological changes associated with Sympathetic NS
Slows digestion
Increases heart rate
Dilates pupils
Diverts blood away from the stomach to muscles (which may need it more)
Physiological changes associated with Parasympathetic NS
Heart rate lowers
Blood pressure lowers
Pupils constrict
Stop sweating
Digestion increases
Bladder control again
Where is the enteric NS found?
The ENS consists of nerve cells (neurons) lining the gastrointestinal tract.
Key functions of Enteric NS
Coordinates rhythmic muscle contractions that move material along the digestive tract.
Regulates gastric acid secretion, changes in blood flow and the release of gut hormones.
Interacts with the immune system
