bro how the fuck do i fit the video into the banana

hi

omfg i finally did it

Rene Descartes viewed cognitive processes and physical processes as two separate entities, and believed the pineal gland connected the two. he also likened the nervous system to hydraulic machines, inspired by automatons.

• basically viewed everything to do with living is a purely mechanical process, later wrote a book about it
• idk i feel like i should add more bullet ppoints so some things to note ig
• lecturer said descartes focused on ventricles and pineal gland too much and the pineal gland actually has nothing to do with this (pineal gland mainly regulates sleep and stuff through circadian rhythm).

Thomas Willis saw them as the same process, → material-soul monism

• psychological attributes of an individual = functionally respondent on cortex, not ventricles.
• i.e., damage to the physical brain structure causes changes in both mental ((b).al and cog.ve) and motor function, while ventricular damage does not do this.
• placed more importance on the cerebral hemispheres, moved attention away from ventricles for the first time in 1500 years.

origins and assumptions of neuro:

• psychological processes are mediated by brain processes; in other words, the two are in close correspondence.
• these brain processes are organised i.e., functions are localised to certain regions.
• brains ar eso well organised that there is a continuity of brain organisation between species. this implies generalisations about animal nervous systems are applicable to humans

origins and assumptions' evil cousin (phrenology)

the belief that psychological attributes correspond to physical skull morphology. psychological traits are localised to brain "organs," and their size correlates to the strength of said trait; in turn, influencing the shape of the skull (endocast).

evaluated

ok im gonna summarise what i just said in list form to make it easier i think.

• Localisation: The idea of mapping different functions to brain regions has been proven; therefore, this aspect of phrenology is not completely invalid.
• Endocasts: The shape of the brain DOES influence the shape of the skull; however, this is not visible from the outside, and the image is very low resolution.
• Cortical Plasticity: In regard to brain "organs" growing and shrinking, this does happen at a smaller scale. Cortical representation does increase with learning.
  • rat experiment showing increase in volume in certain cortical regions upon learning new tasks.

"Scientific Phrenology" 1

Marie Jean Pierre Flourens' (1794-1867) experimental ablation led to the 'discovery' of three functionally seperate regions:

• The Medulla; in charge of respiration/vegetative function. Top of spinal chord.
• The Cerebellum; in charge of motor control. Behind medulla.
• The Cereberum; in charge of perception, intellect, and 'will.' These are your 'big bits' or something.
  • Florens could not find a localised function of the cereberum; however, this was likely "due to unsophisticated psychology" (Prof words, not mine)

  "Scientific Phreology" 3

  David Ferrier combined electrical stimulation and experimental ablation. This was further combined with an improved model of behavioural observation. Localised a bunch of sesory and motor regions. Ferrier's Mistake

  • had tea with monkey
  • ablate angular gyrus in monkey
  • monkey no longer responds to teacup being placed in front of it, but still drinks from it if cup is placed in hand; Ferrier thhiks, "must be blind."
  • was actually hemispatial neglect

  Vasculature and Metabolism

  Roy and Sherrington (1890) noticed:

  • Blood volume in local regions of cortex increased i.r. to nerve stimulation.
  • Proposed neuronal metabolic activity caused the accumulation of chemicals that decrease vasculative resistance.
    • subsequent increase in blood flow until baseline function is restored.
    • increased blood flow = modern functional MRI (& near-infared spectroscopy) basis.

"Scientific Phrenology" 2

Gustav Fritsch and Edward Hitzig (1870) used direct electrical stimulation on the exposed cereberal cortex of dogs.

• Motor strip; discovered systematic relationship between the part stimulated along the motor strip and subsequent movement of corresponding body part; i.e.,
• Contralateral control; basically stimulating the 'leg-move-part' on the left side (of brain) caused physical movement in the right side (of body).

Microanatomy

1830s: Cell theory takes biology by storm. Cells are now the established fundamental building block of biological tissue,,,, but not for the brain. However, this is explained by Golgi, Cajal, Waldeyer, and the Neuron Doctrine. Golgi believed the brain was one big blob, but Cajal's golgi stain revealed that the brain consisted of many filaments, spaced apart. Cajal was the first to identify neurons. Timeline:

• 1888 = synapses, dendritic spine, neuron doctrine.
• 1887 = axon as output
• 1980s = synaptic modifications as basis for recovery

Cajal's Explanations

• Neurones communicate with each other via chemical messages across cells via the synapse.
• dendritic spines = neuronal input source
• axons = neuronal output source. Long protuberances out of neurons.
• synaptic modification facilitates memory. One change in cell function leads to influencing the next.
  • potential basis for learning, memory, plasticity, behavioural modification.

  cytoarchitecture

  Key figure: Korbinian Brodmann. Cerebral cortex:

  • Most neurons (cell bodies, where nuclei are,) were spread out across the neocortex where the grey matter was (back of brain).
  • These cell bodies are arranged in 6 layers
  • relative sizes of layers varied across regions.

  ⤷ Brodmann's Areas

  • Still used
  • Homologies between human and monkey brains highlighted, allowed by observation.