5A/Chapter Six - Understanding The Role Of The Brain/ + Others Flashcards
Phrenology
The study of the shape of the skull as an indicator of one’s mental faculties and character traits
CT
Computerised Tomography
Provides information on structure only
Combines a series of x-rays taken at different angles to create a black and white 2D image of a cross section of the brain
Patient must be injected with an iodine-based substance (contrast) that makes certain brain structures more visible
Used to assess the damage caused by strokes, injuries, tumours and disease
MRI
Magnetic Resonance Imaging
Structure Only
Produces a more detailed image than a CT and does not require harmful x-rays
A person’s head is placed in a chamber and a magnetic field is created around it; radio waves are pulsed to vibrate brain neurons. The vibrations are detected and used to produce the image
PET
Positron Emission Tomography
Structure And Function
Patients have radioactive glucose injected into bloodstream and electrodes placed around their head to detect positrons emitted by the radioactive glucose (harmless)
Patients are asked to engage in a specific task, the amount of glucose used by each area of the brain is recorded
fMRI
Functional Magnetic Resonance Imaging
Structure And Function
Works like a standard MRI while also making brain activity visible on a computer screen
fMRI detects the differences between oxygenated and deoxygenated blood in the brain as it undertakes different tasks, with the assumption that active brain structures will require more oxygen
Advantages: No radioactive substances required, more detailed and accurate than PET scans
Brain Heart Debate/Mind Body Problem
BHD - the question of whether thoughts, feelings and behaviours originate from the brain or the heart
MBP - extent to which the mind and body are the same or seperate things
Neuroplasticity
Is the ability of the brain to change its structure or function in response to experience or environmental stimulation
Synaptogenesis/Synaptic Pruning/Myelination
S - the process of forming new synapses
SP - the elimination of unused synapses
M - the formation and development of myelin around the axon of the neuron, this helps to make messages more efficient and quick.
Factors Influencing Brain Plasticity
Experience-Expectant-
Involves brain development triggered by specific environmental cues that the brain expects to encounter at certain times
Experience-Dependent-
Involves the unique and personal brain changes that take place when different situations occurs
Adaptive Plasticity
The brain’s ability to restore adequate neural functioning over time after sustaining injury
- once neurons and other cells in the brain are damaged or die, they typically do not regenerate.
- the remaining healthy neurons are responsible for recovery from damage
- adaptive plasticity can occur throughout the whole lifespan
- however, it is more efficient in younger people due to higher levels of developmental plasticity
Types Of Adaptive Plasticity
Sprouting-
A neuron develops new branches at the dendrites or axons which allows it to form new neural connections where activity has been prevented or depleted
Rerouting-
A neuron forms a new connection with another undamaged neuron and abandon the damaged neuron, this allows new neural connections to be formed
Neurodegenerative Disease/Neurological Disorder
Disease - An incurable condition that involves the progressive death of neurons
Disorder - Any disorder of the nervous system, including the brain, spinal cord or nerves
Acquired Brain Injury
All types of brain injury that occur after birth
Types Of ABIs
Traumatic Brain Injury-
damage to the brain caused by an external force (e.g - accident, sports, assaults)
Non-Traumatic Brain Injury-
damage to the brain caused by internal factors, such as a lack of oxygen or tumour (e.g - stroke, tumour, aneurysm, hypoxia, substance abuse)
Types Of TBIs
Direct Impact Injury
Acceleration-Deacceleration Injury
Shock Wave Injury
