3) Mapping Mind, Nature & Nurture, Questions Flashcards
phrenology
1800s
- one of the first attempts to map mind to brain
- evaluate bumps
- super incorrect, relied on anecdotal observation
EEG : electroencephalograph
- Non invasive
- Electrodes placed on scalp
- Device that measures electrical activity generated by brain
- Can infer wakefulness, dream or not, which regions of brain are active at the time
Weakness of EEG
Average activity that reaches surface of scalp tells us WHEN rather than where activity is happening
What is neuroimaging?
brain scans / imaging techniques that allow us to peer inside brain structure or functions
Which neuroimaging techniques allow us to visualize brain structure?
CT & MRI
CT Scans
Computed Tomography
- Non invasive
- Scanning technique using multiple X rays to construct 3D images of brain structure
MRI Images
Magnetic Resonance Imaging
- Non invasive
- Technique that uses magnetic fields to indirectly visualize brain structure
- Measures release of energy from water in tissues after exposing
What is the weakness of CT and MRI scans?
show brain structure only, not activity
PET
Positron Emission Tomography
- Functional imaging technique, measures consumption of glucose-ish molecules
- Inject radioactive glucose-like molecules
- Yield picture of neural activity in diff regions of brain in response to stimuli
- Works cuz cells increase intake of glucose when active
Which neuroimaging technique is invasive?
PET
What is the weakness of PET?
invasive, was later replaced by fMRI
fMRI
Functional Magnetic Resonance Imaging
- Indirect indicator, non invasive
- Technique that uses magnetic fields to visualize brain activity using changes in blood oxygen level
- Brain cells require more oxygen when busy means increased oxygen in blood flowing to active brain areas
Which neuroimaging technique involves changes in blood oxygen level?
fMRI
-> visualize brain activity
Which neuroimaging technique measures consumption of radioactive glucose?
PET
-> shows activity in diff regions
Which neuroimaging technique is good at detecting soft tissues like brain tumours?
MRI
-> better than CT for detecting soft tissue
Which neuroimaging technique involves using X rays?
CT
-> constructs 3D images
Default mode network
regions associated with spontaneous thoughts (ex/ daydreaming)
Brain is active even when we’re doing nothing
Discovered by fMRI researchers
What network did fMRI help discover?
Default Mode Network
MEG
Magnetoencephalography
- Detect electrical activity in brain by measuring tiny magnetic fields on skull surface
- Non invasive
- ability to track brain changes over super brief time intervals
Describe the difference in time between brain changes measured in MEG vs PET and fMRI
PET and fMRI measure brain changes second by second
vs
MEG measures changes millisecond by millisecond
What are some misinterpretations of neuroimaging techniques?
- Assuming that functional brain images (like PET and fMRI) are actual photos of brain in action
- Neuro seduction
- There’s risk of chance findings cuz things get complex when comparing activity of hundreds of brain areas
What is neuro seduction?
Placing unwarranted confidence in evidence derived from brain-imaging studies
- Do not assume the imaging techniques can read minds, or be more persuaded just becuz it’s scientific
Functional brain images are not actual photos of brain in action, what are they?
ex/ PET and fMRI
- Photo is subtraction of brain activity of control task from experimental task
- Light up means active, but dunno if neurons are inhibited or excited
- Doesn’t allow definitive diagnoses of mental disorders (but can be helpful)
What are genes?
Sections of DNA that contain hereditary info
Allele
one of two or more alternative forms of a gene
Homozygous vs heterozygous
homo = when 2 alleles of a gene in the pair are the same
heter = when they diff