Cognitive Neuroscience: A Very Short Introduction

Richard Passingham, Oxford University Press 2016
  1. A recent field
  2. Perceiving
  3. Attending
  4. Remembering
  5. Reasoning
  6. Deciding
  7. Checking
  8. Acting
  9. The future
Notable people: Gilbert Ryle, Donald Broadbent, Anne Treisman, Ulrig Neisser, George Miller, Michael Gazzaniga, David Milner and Mel Goodale, Joseph Zihl, Semir Zeki, Kalanit Grill-Spector and Rafael Malach, Larry Weiskrantz, philosopher Ned Block, philosohper David Chalmers, French philosopher Henri Bergson, Michael Posner, 

Terms: 
Positron emission tomography - uses radio active materials and radio tracers to measure organ and tissue function
Functional magnetic brain imaging - measures cerebral blood flow(Hemodynamics) and neuronal activation.
Amygdala - in temporal lobe important for the memory of emotion, strongly studied with fear due to the immediacy of the activation
Subgenual Cingulate Cortex - Brodmann area 25, region responsible for serotonin transporters and for regulating many systems, which include affecting sleep and appetite, mood, anxiety, self esteem.
Serotonin - mood stabilizer for sleeping, eating, and digesting.
Ventral - towards lower surface.
Dorsal - towards upper surface of the primate brain.
Transcranial magnetic brain stimulation(TMS) - noninvasive use of magnetic fields to stimulate nerve cells.
Concentration gradient - rate of change for molecules in a solute or gas, as they equalize their density.
Diffusion - the equalization of a concentration gradient.
Diffusion weighted magnetic resonance imaging(DWI) - use of water diffusion in biological tissue to generate contrast for the image.
Synesthesia - stimuli in one or more cognitive pathways generate perceptual experience in another.
Adaptive suppression - If the same stimulus is repeated within a short period there is less activation with repetition.
Multi-voxel pattern analysis - a statistical approach to brain imaging, analyzing the pattern of activation that differ across voxels of the brain image when looking at different objects.
Salience network - regions of the brain that select which stimuli to give our attention to, and coordinates neural response to.
Anatomical system - group of areas that are closely interconnected, behavioural tasks are connected .
Resting state covariance - spontaneous activity in areas varies in synchrony for anatomical systems.

Briefs:
Part of the existence of cognitive neuroscience came from the question of how from psychology as it hung on the belief of behaviourism. One of which philosophy explored with the theory of the mind.
Dualism is the million dollar mistake of the brain. It is a single unified system, the brain is of the whole body.
Studying brain function by testing people who have lost brain regions shows disability, thus proving regionality.
Methods to visualize activation in the brain(PET, fMRI)
Brain imaging shows blood flow as it brings oxygen and glucose needed for metabolism, thus showing an indirect measure of activation, and not activity.
Activation is not measured but rather the difference from control and applied.
The degree of difference is important when compared to depressed people when looking at the amygdala and the subgenual cingulate cortex.
People who are depressed are thinking sad thoughts.
Brain imaging shows us the mental state of the brain, not why they are in them.
Understanding the activity in the brain will help us answer questions that psychology cannot.
Lateral occipital complex, the border between the occipital and temporal lobe is where object recognition takes place. Another system is responsible for using the shape to guide action.
There is no single path of input to output, parallel paths occur for different information from the senses and are processed first by primary sensory areas then relayed through secondary areas.
Convention gives each primary sensory area a 1,  and secondary areas in ascending order. V1 >> V2
Only the dorsal visual system has direct connections to the frontal lob areas for movement.
Human middle temporal complex connects to the parietal cortex, of info about movement of objects.
Parallel means we have different operations carried out at the same time for high speed of processing.
Because of the parallelism, one part of the brain may be damaged while the other works perfectly.
The brain is patchwork of discrete areas, which each area consisting of a host of neurons arranged in sex layers, being many neurons thick. Areas differ in thickness, density and frequency of the different neuron types.
Neurons have cell bodies, and long axons. These fibres are bundles and can travel long distances to connect areas far apart. The pattern of the connections allow different areas to do different operations. Localisation of function can hold because each area receives a unique pattern of connections and send out a unique pattern to other areas. Incoming connections determine the information that the area can process; outgoing connections determine the influence on the other areas.
Sensory processing of the body is mapped to brain regions, where brain tissue size is relative to the importance of the body part.
If peripheral sense organs are damaged/missing, sensory cortex activity is perceived as an external force.
Sensory integration are through sensory modalities through common areas called multimodal areas. They include the parietal cortex, and the prefrontal cortex and will activate regardless of the stimuli type.
Connections are charted via DWI as water diffuses along the fibre tracts, showcasing the orientation of the tracts and origin/termination points.
The lateral occipital complex recognizes objects based on their shape and colour, regions V1, V2, V3 will activate for complete to incomplete objects with different degrees of scrabbling. Earlier stages process elements, and later stages integrate them via a hierarchical arrangement of higher order neurons in area B receiving input from lower order neurons in A, and C from B, etc. This allows us to recognize different shapes at different angles and sizes.
Learning in the visual system occurs when lower order neurons respond maximally to objects with a particular view, and higher order neurons integrate the information from the lower order, learning to respond of the object irrespective of the view.
Object recognition and classification depend on hierarchical organisation. Higher visual areas in the inferior temporal cortex relate the patterns of activation to different animals and classifications.
Awareness is processed in different regions of the brain, thus if one part fails, then movement, or orientation, etc. can still be used to be aware of such stimuli from the working brain regions.

Chapter 3 attending

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