Chapter 2: Memory and the brain Flashcards
traumatic brain injury (TBI)
caused by a blow or jolt to the head, or a penetrative head injury. Normal brain function disrupted
The more severe the injury, longer unconsciousness or amnesia, more brain damage, poorer chance of recovery
why doesn’t TBI lead to theoretical conclusions about nature of memory
because it is hard to separate memory deficits from other factors
Alcoholic Korsakoff syndromes
drinking too much, eating too little, memory deficits prominent
Henry Molaison HM
most influential neuropsychological case
Temporal lobe epilepsy/ surgically removed parts of the hippocampus
New information retention damage
HM’s deficits were limited to episodic long term memory
double dissociation
a term particularly used in neuropsychology when two patient groups show opposite patterns of deficit
Ex: STM normal and impaired LTM, or normal LTM and impaired STM
converging operations
carrying out a whole series of operations and experiments using different methods and different participant groups, all focused on the same theoretical question
Computerized tomography (CT)
rotating an x-ray tube around head, provides multiple viewpoints of brain fed into computer for 3D representation of the brain
Magnetic resonance imaging (MRI)
places head in strong magnetic field, scammer emits radio waves
Grey matter (neuronal cell bodies), white matter (axons- linking different brain areas), and cerebrospinal fluid all emit different energy due to different absorption so provides 3D image
No radiation, more precise images than CT
Diffusion tensor imaging (DTI)
takes advantage of myelin sheaths which around white matter are relatively fatty, causing water within to flow along that fiber. Allows mapping of important white matter bundles that transfer information from one area of the brain to another
Transcranial magnetic stimulation (TMS)
a less invasive method of influencing the brain, a current is passed through a set of coils held close to the participants head
Causes magnetic field that can temporarily polarize or depolarize the brain area
Limited to areas of the brain near surface, discomfort
Electroencephalography (EEG)
recording the ongoing electrical activity of the human brain. Noninvasive, picks up electrical activity of the brain through electrodes on the scalp
Used to detect epileptic foci that can result in seizures
Event related potentials (ERPs)
more precise way of evaluating the brain’s response to specific cognitive activities through the pattern of EEG activity obtained by averaging the brain responses to the same stimulus presented repeatedly. Precise timing, most sensitive to gyri- peaks
Magnetic encephalography (MEG)
a system whereby the activity of neurons within the brain is detected through the tiny magnetic fields that their activity generates. Most sensitive to the activity in sulci- the valleys within in the folds of the brain
Positron emission tomography (PET)
method where radioactively labeled substances are introduced into the bloodstream and subsequently monitored to measure physiological activation. Injected into the bloodstream, carried to brain
Functional magnetic resonance imaging (fMRI)
measures the flow of oxygen within different areas of the brain, on assumption the active area of the brain will utilize more oxygen
When oxygen is depleted hemoglobin magnetic resonance signal charge, better spatial resolution, poor temporal resolution
