Lecture 1, week 1, 24th Feb Flashcards
Introduce cognitive neuroscience and theoretical perspectives, brain structure, functional organisation, basic neuroanatomy.
What is the mind body problem?
What is the brain and how does it create our mental world.
Explain Dualism.
The mind is non-physical and immortal
* The body is physical and mortal
* Two different substances that
interact in the pineal gland
Explain dual aspect theory.
- Mind and brain are different aspects or properties of the same thing
- Mental properties as emergent
- Mind emerges from the brain but cannot be fully explained by the lower-level brain components
Explain reductionism.
- “Memory”, “attention”, etc. are just useful terms that can eventually be replaced by description at a biological level
- Psychology will eventually be replaced by neuroscience
What is cognitive neuroscience?
A mix between cognitive psychology- An area of psychology that studies mental processes such as thinking, memory, planning, reasoning, attention and perception. (Cognitive psych studies use the cognitive approach- Observations of behaviour, rather than observations of the brain
during behaviour… Models of cognition that are not directly constrained by the brain
* e.g., information processing models popular from 1950s onwards) and neuroscience- science of the nervous system, its structure, and function.
So… in total, cognitive neuroscience is a study that aims to provide a brain-based account of cognition.
Explain Visual Search in terms of how cognitive neuroscience works.
Visual Search: * Move eyes and fixate on location
* Extract information
* Identify objects and match to target * Decide when to stop searching…. We then made a guided search model using the cognitive approach (slide 45 image for reference). Cognitive neuroscience then added a neural representation (The way in which properties of the outside world manifest themselves in the neural signal. Neural representations are not synonymous with mental representations (unless you are a reductionist)) The neurobiology of visual search is that … * Visually guided eye movements (“saccades”)
* LGN: lateral geniculate nucleus
* V1/V2/V3/V4: visual areas * (MT/V5: motion)
* Visual maps (priority map)
* LIP: lateral intraparietal cortex * FEF: frontal eye fields
* SC: superior colliculus
* Decision about motor responses
Explain the progression of cognitive neuroscience.
1970s
structural imaging methods enable precise images of the brain (and brain lesions)
1980s
early functional imaging adapted to models of cognition developed by psychologists
1985
brain stimulation is first used
1990
level of oxygen in blood is used as a measure of cognitive function (the principle behind fMRI)
What are the different methods of cognitive neuroscience?
There are many different types such as EEG, TMS and MEg that use either recodring or stimulation, invaisve or non-invasive techniques or electrial, electromagnetic or hemodynamic brain properties. ***PROBABLY DO NOT NEED TO KNOW, refer to table in slide 51 if needed.
What is a neuron?
A nervous system cell with special properties that allow it to communicate directly with other cells.
Explain the structure of a neuron.
Nucleus, cell body, denrites, myelin sheath, nodes of ranvier, axon, terminal buttons.
Explain a synapse.
- The place where axons and dendrites meet
- Axons send electrical signals (action
potential) away from the cell body - Dendrites receive signals primarily via chemical signals (neurotransmitters)
How are these organised in the brain?
Grey matter & white matter
* Grey matter = cell bodies of neurons
* White matter = axons, myelin, and glia (support) cells
* Axon tracts occur within hemispheres, between hemispheres, and between cortical and subcortical regions
Explain the corpus callosum.
Massive white matter tract linking the two hemispheres
How many neurons do we have
- The human brain has about 86 billion neurons
- Each neuron might connect with 10,000 others
- We are not born with our full set of neurons (neurogenesis) * We lose one cortical neuron per second.
Explain the regions of the brain and where they are.
Dorsal/superior (towards the top), Ventral/inferior (towards the bottom), anterior/rostral (front), posterior/caudal (towards the back, lateral (towards the outside), medial (towards the middle) slide 63
Explain functional specialisation.
Neurons responding to similar types of information tend to be grouped together
* Important to consider computational processes rather than simple localization, “It’s more important to focus on how the brain processes information as a whole, rather than just identifying specific areas responsible for particular tasks.”
What is the idea of modularity.
The idea that the different regions of the brain are restricted in the type of information they process (i.e., domain specificity)
What is interactivity?
- Stages of processing are not strictly separate
- Later stages can begin before early stages are complete
- Later stages can influence early ones (top- down processing) ***BASICALLY, the brain does lots of stuff at once instead of just doing a step by step process in order super quickly.
What is the cerebral cortex?
- 2 hemispheres
- Outside surface is
made up of four lobes - Each lobe has a characteristic set of gyri (ridges) and sulci (valleys)
What are Brodmanns areas?
Different regions of cortex defined by the layered composition of cells (cytoarchitecture)
* 52 areas: BA1 to BA52
What are the three subcortical structures and explain them
Basal ganglia- Includes caudate & putamen
Limbic System- Includes amygdala & hippocampus
Diencephalon- Includes thalamus & hypothalamus
Explain the midbrain, hindbrain and cerebellum.
Midbrain- Subcortical routes for hearing (inferior colliculi) and gaze orienting (superior colliculi)
Hindbrain- Pons, medulla oblongata which are involved in breathing and heart rate
Cerebellum-
Primary function is to integrate information about motor commands with sensory feedback to enable smooth movement and dexterity.
