Unit 2 Flashcards
For humans, what is the front/back of brain?
What about for animals?
Anterior/Posterior (before, after)
Rostral/Caudal (beak, tail)
For humans, what is the ‘inside/outside’ of brain?
What about for animals?
Medial/Lateral (inside, outside)
For humans, what is the above/below of brain?
What about for animals?
Superior/Inferior (above, below)
Dorsal/Ventral (back, belly)
Horizontal vs. Coronal vs. Sagittal planes
Horizontal: “horizon” A horizontal slice. a top-down perspective
Coronal: “crown” a top-down cut that views the front/back.
Sagittal: “arrow” A 3D view from side. Cut through the face
Grey Matter vs. White Matter
Grey Matter: Where cells communicate. Where synapses are. Forms the cortex. The outermost layer. (inside layer for spinal cord)
White Matter: Axons that connect the grey matter. Highways or wires. A bunch of axons. Myelination. Inside layer. (outside for spinal cord)
What are Sulci and Gyri?
They make up the folds of the brain, helping to create more space and surface area for grey matter.
Sulci: The grooves on the brain’s surface.
Gyri: The bumps between sulci.
Main Sulci
(What are they? Purpose?)
They are landmarks for the brain to divide the brain into regions.
Longitudinal Sulcus: has its own gyrification. splits left and right hemisphere. (anterior-posterior cut)
Central Sulcus: no gyrification itself. divides parietal and frontal lobes. (medial-lateral cut)
Lateral Sulcus: at the side of the brain. has its own sulci and gyri. has insular cortex.
Insular cortex
grey matter area deep within the lateral sulcus. not visible from the surface.
What percentage of grey matter of the brain is in the cerebellum?
40-60%?
What are the four lobes of the brain? Acronym?
Frontal Parietal Occipital Temporal
(FPOT)
What is the neuron doctrine?
The nervous system is made of many individual cells that don’t touch.
What is the charge of a neuron at its resting state?
-70mV
Why do neurons not just keep firing?
Neurotransmitters tell the postsynaptic neuron whether to fire or not.
Feature detectors
The first neurons that activate in response to some sensory stimulus. They contain the lowest level of neural processing, the simplest possible information about the stimulus.
How is information processed from feature detectors?
Hierarchical Processing.
Subsequent neural activity in steps that makes sense of the basic info. Meaning increases at each step (low –> high level). Neurons interact with many parts of the brain, making the interpretation more abstract at each step.
Neural Representation
Everything we experience is represented in our nervous system.
we can’t do anything without nerves. our brain can’t do anything by itself.
Three types of “coding” about how information is represented by neurons.
Brain neural coding strategies.
Specificity Coding: A specific neuron activates in response to feature detectors, representing a specific pattern.
Population Coding: A group of neurons activate in response to feature detectors to represent an interpretation.
Sparse Coding: Some neurons of a region activate to feature detectors.
When getting more familiar with a particular stimulus (eg. Bill), what happens to feature detectors and connections?
Feature detectors don’t change (the raw data remains the same).
The connections to other regions get more accurate.
How do neurons translate to our conscious perception of some stimulus (eg. Bill’s face)?
Mind-body problem. There’s no neuroscience answer to this. Philosophical.
Localized vs. Distributed Processing
Localized: one region does the higher-level processing
Distributed: multiple regions collaborate in higher-level processing
Structural vs. Functional Connectivity
How can researchers explore this connectivity?
Structural: physically connected (through white matter track)
Functional: one area’s activation activates together with another. correlated activity.
Using precise structural (eg. DTI for structural connectivity) or functional (eg. fMRI/fNIRS for functional connectivity) scans.
What are the 3 ways researchers differentiate brain regions?
Macroanatomical Features: either Sulci and Gyri (eg. AAL-3)
Microanatomical Features: neurotransmitter receptors, myelin density, cytoarchitecture, cortical thickness.
Connectivity:
What atlas looks at connectivity? What is connectivity?
Brainnetome.
See which coactivate or connected by white matter (structural/functional)
What are brainspaces? 2 Main ones?
Coordinate spaces for the brain.
MNI (a combination of 152 MRIs)
Talairach - from a dissected brain
