Flashcards in Intro 1-Biological Psychology Deck (160)
What was Aristotle's argument?
That the heart, rather than the brain, was the centre of the mind
What were some of the reasons behind Aristotles argument?
All animals have a heart but not all have a brain eg invertebrates have sensations but no brain. Also the heart is sensitive to touch, unlike the brain
What was Descartes view?
Tried to explain the brain in terms of machines. Also spoke about dualism
What is dualism?
The philosophical position that behaviour is controlled by two entities; the mind and the body
What was Gall's view?
Brain is an organ of the mind which distinct faculties. The size of the brain measures the power, and the shape of the brain is determined by development of various organs
What is phrenology?
As the skull takes shape from brain, surface of skull can be read as an accurate index of psychological aptitudes and tendencies
What tool was used in phrenology?
Lavery's Electric Phrenometer
What was Golgi's contribution to the understanding of the brain?
Using his technique of silver staining he discovered the brain was a large network of interconnected tubes, meaning it would be misleading to think about functional localisation
Who disagreed with Golgi, and why?
Santiago Roman y Cajal later discovered, using a similar technique, that nerve cells are actually discrete entities
What did Brodmann discover?
That cells are grouped in areas, and these areas have different functions
What did Kleist do?
Comprehensive functional mapping of cerebral cortex using case notes from WW1 head wound casualties, and discovered that phrenologists' language areas differ from Broca and Wernicke's area
What study did Bailey and Von Bonin do?
Cortico-cortical connexions in chimpanzees found the brain is an interconnected network
What are the ways of studying the brain?
Cytoarchitecture, neuropsychology, imaging techniques, listening techniques, EEG (and event related potentials), near infra-red spectroscopy, direct brain stimulation, transcranial magnetic stimulation
What is cytoarchitecture?
Study of cellular composition of central nervous system's tissues under the microscope, to discover connectivity and anatomical function
How can neuropsychology be used to study the brain?
Eg Phineas Gage where the brain lesions changed personality, decision making and sense of time
What is a negative point of neuropsychology?
Have to wait for the patient to die to discover function and damage to brain areas
How can imaging techniques be used to study the brain?
MRI studies brain anatomy, fMRI studies brain function (correlation not causation), subtraction method
How can listening techniques be used to study the brain?
Single cell recordings, as with Hubel and Wiesel's study
What is near infra-red spectroscopy?
Fibre optic cables and sensitive detectors used. Reflections as light bounces off cortex. Heightened activity among neurons increases scattering. Light into 3cm in cortex with spatial specificity of 0.5cm with m5 resolution
What did D'Arsonval and Thompson do?
Contributed to the history of magnetic stimulation of the nervous system. Early attempts to stimulate the brain using a magnetic field
What is the neuronal membrane?
Surrounds every cell in the body. It is intracellular and extracellular
What is the phospholipid bilayer?
It contains ion pumps and channels. Ion movement across the membrane causes electrical signals which affects the ion channels which can either be resting (open), voltage gated, ligand gated or mechanically gated
What are the ions in the intra/extracellular fluid?
Sodium (Na+), Potassium (K+), Chloride (Cl-), and large negative ions (A-)
What forces cause the movement of ions in and out of the cell?
Concentration (high to low density) (Diffusion), and electrical (negative to positive) (balance)
What happens in the membrane at rest?
Sodium ion channels are closed so sodium is free to move across the membrane. Some potassium ion channels are always open. Neuron has more positive ions outside cell so cell is negatively charged. Na/K pump causes imbalance as always pushes three positive sodium out and two positive potassium in
What is the resting membrane potential?
At rest the neuron is negatively charged at -65mv
How do action potentials occur?
Equilibrium is upset by stimulation. If large enough the resting potential becomes an action potential which is generated at the axon hillock if net charge is above the threshold of -50mv, and it is then propagated down the axon
How is sodium linked to the rise of the action potential?
Changes in electrical activity/action potential due to ion movement. Cell stimulated above threshold so sodium ion channels open. Sodium attracted in the cell due to more Na+ outside. Also because cell is negatively charged. This influx causes the cell to become more positive
How is potassium linked to the fall of the action potential?
The cell is positively charged when action potential reaches peak. Electrical force changes and potassium is attracted outside cell (which is negative). Still more potassium in the cell than out, so concentration force also forces potassium out of the cell