Week 1: Principles Of Cognitive Neuroscience Flashcards
What is cognitive Neuroscience?
The research field that studies how our mental abilities are implemented in the brain.
Between what two fields does cognitive neuroscience bridge the gap?
Neuroscience and psychology
What discipline should cognitive neuroscience not be confused with?
Neuropsychology
What is the subject of cognitive neuroscience?
- focuses mostly on healthy humans
- also uses insights from studies on patients, non-human animals and computer science / AI / robotics
What is the goal of cognitive neuroscience ?
Aims to understand the entire neural realisation of a cognitive function (often not precisely characterizable at the level of a single neuron)
What kind of properties does cognitive neuroscience study?
System properties of cognitive function (entire realisation vs single neurons)
How relevant is cognitive Neuroscience?
- primarily a basic science
- but also considerable relevance for brain-related medical fields, such as neurology, psychiatry, neurosurgery
How is cognitive Neuroscience different from animal neuroscience?
- different functions (e.g. language)
- different way that behaviour is brought about (conditioning vs instructions)
How are Computational models being used in cognitive neuroscience?
In many cases only a few computational models are available (few exceptions, such as reinforcement learning)
What are three different types of studying the link between mind and brain?
- Lesions
- Stimulation
- Recording
What are the key challenges in cognitive neuroscience?
- brain data is limited in spatial and temporal resolution
- brain data is limited in number of sampling points → problem for modelling in high-dimensional spaces
- we don’t know the „ground truth“
How much do brain and nervous system disorders cost per year?
492.200.000.000 USD
What is the mind-body problem?
How does the mind relate to the body? are they one thing?
What is Dualism?
- Descartes Theory of the Mind
- body (res extensa, the physical, mortal) and mind (res cogitans, non-physical, immortal) are separate
- but they interact (at „portal“ → pineal gland)
How is it observable that dualism is still believed today?
- beliefs in afterlife
- „psychosomatic“ medicine
- opening of windows in hospitals (after someone has died)
Who were defenders of dualism?
- René descartes
- Socrates
- Plato
What was Descartes error according to damasio
- descartes ascribed reason to mind and emotion to the body
- our decision-making (reason) however cannot be separated from our emotions (body)
What is the somatic marker hypothesis?
Our decision making (mind) is guided by emotional somatic mechanisms in PFC (body). (By Damasio)
What is Damasio’s error?
He implies a distinction between somatic and cognitive
What is the Cartesian Theater?
- way to critique Descartes Dualism
- according to Descartes there is a central place in the brain where all inputs come together (screen, stage) and are „viewed“ by an observer,
- according to Dennet, this would lead to an infinite regress → who views the observers screen?
What is Holism?
- every part of the brain is responsible for every cognitive function
→ if you start losing parts of the brain, all cognitive abilities will start to gradually deteriorate
Who was the „founder“ of Holism?
Marie-Jean-Pierre Flourens (1794 - 1867)
Other proponent: Karl Lashley
What is Equipotientiality?
The Theory that all brain areas are responsible for all cognitive functions (Holism)
What was Flourens method of studying the brain?
Ablation experiments (with animals)
= remove parts of the animals brain and see how it affects its function
What is Phrenology?
- idea that differences in cognition can be mapped onto differences in skull shape
- different brain regions perform different functions and are associated with different behaviours
- size of those regions produces distortions of skull and correlate with individual differences in cognition and personality
Who was the „founder“ of Phrenology?
Franz Joseph Gall
What was Gall‘s method of studying the brain?
Cranioscopy
→ mapping of „innate faculties“ to bumps on the head
according to Gall, intellectual faculties are…
… innate
… controlled by the brain
… each faculty has a dedicated „organ“ in the brain
…development is reflected in the form of the skull
What is Localization?
- a given part of the brain is responsible for only one cognitive function
- one-to-one mapping
- idea emerged from phrenology
Who found the first clear evidence for localisation?
Paul Broca
What did Paul Broca do?
- first demonstration of functional localisation in human brain
- Patient with left prefrontal lesion with intact speech perception, but inability to speak anything but „tan“
- postmortem confirmed localised lesion
- repeated with 12 other patients
What where methods of localisation?
- Visual field maps (Gordon Holmes) → bullet holes in specific brain areas, lead to disturbed visual field representation
- Direct Brain Stimulation (Wilder Penfield) → stimulation of specific sites induces spontaneous movement or perceptions → Motor Homunculus
What’s wrong with strict localisation?
No sparseness
→ unclear whether this is inherent feature of the brain or due to the way in which we define cognitive processes
What theory is accepted today? Holistic or Localisation?
- neither is entirely correct
- there is no 1:1 mapping of cognitive functions and brain regions
- brain performs analysis as functional networks rather than individual activation
- modern localisation maps (with help of brain imaging) imply strong localisation if cognitive functions
What are lesion studies useful for?
To study modularity of cognitive function and establish double dissociation
What is a single dissociation?
- when a lesion to brain area X impairs the ability to do task A but not B
→ brain area X and A are associated
→ brain area X and B are dissociated
What are double dissociations?
- identifies whether two cognitive functions are independent of each other
- when damage to area X impairs task A but not B and damage to area Y impairs task B but not A
