Biological Psychology Flashcards
What is contained in the central nervous system (CNS) ?
Brain and spinal cord
What is contained in the peripheral nervous system (PNS) ?
Everything else
Nerves - motor pathways and sensory pathways
What are the three main parts of the brain ?
Cerebrum
Cerebellum
Brain stem
What does contralateral mean ?
Opposite side of the brain
What does ipsilateral mean ?
Same side of the brain
How much blood flow does the brain receive ?
20% of the blood from the heart goes to the brain
What is the anatomical term for up/superior ?
Dorsal
What is the anatomical term for down/inferior ?
Ventral
What is the anatomical term for front/anterior ?
Rostral
What is the anatomical term for back/posterior ?
Caudal
What does medial mean ?
Toward the middle
What does lateral mean ?
Toward the side/outside
Where is the frontal plane ?
Parallel to forehead
Splits front and back
Where is the sagittal plane ?
Parallel to the wall
Splits left and right
Where is the horizontal plane ?
Parallel to the ground
Splits top and bottom
What is grey matter ?
Cell bodies and dendrites
e.g. cortex, basal ganglia, thalamus
What is white matter ?
Myelinated axons
e.g. the corpus callosum
What is the pathway that connects the left and right hemisphere called ?
Commissure
What is the corpus callosum ?
Translates to ‘hard body’
The largest fibre bundle connects the two hemispheres of the brain
What is meninges ?
3 layers of tissue that protects the brain and spinal cord (CNS)
What are the 3 layers of meninges ?
Dura mater
Arachnoid membrane
Pia mater
What is cerebrospinal fluid (CSF) ?
A clear liquid that fills the subarachnoid space
Functions: shock absorber, buoyance, prevents carrying the weight of the brain
What are ventricles ?
‘little bellies’
Hollow cavities filled with CFS
How is CFS produced ?
Filtering blood
What is the blood-barrier ?
A semipermeable barrier
Lipid soluble substances can pass through
Substances with large molecules must be actively transported through the walls
What is the purpose of the blood-brain barrier ?
Maintain stable environment
Protection from potentially disruptive/damaging chemicals
What is the cerebral cortex ?
The outer surface of the cerebrum
3mm thick
Folded to allow a bigger surface area
What are the clefs and grooves called in the cerebral cortex ?
Sulci
Major grooves = Fissures
Folds and bulges = Gyri
What are the 4 lobes of the brain called ?
Frontal
Parietal
Occipital
Temporal
Describe the frontal lobe
Front of brain
Anterior of the cortex
Rostral to parietal lobe
Dorsal to temporal lobe
Functions: motor and cognition, higher order function
Describe the parietal lobe
Near the back
Caudal to frontal lobe
Dorsal to temporal lobe
Function: somatosensory
Describes the occipital lobe
In the back of the head
Caudal to parietal and temporal lobes
Function: vision
Describe the temporal lobe
The temple
Rostral to occipital lobe
Ventral to parietal and frontal lobes
Function: hearing, vision, cognition, emotion
What are the primary areas ?
Primary somatosensory cortex
Primary visual cortex
Primary auditory cortex
Primary motor cortex
They are all contralateral
What is the role of sensory association areas ?
Receive and analyse info from primary regions
What is the Basal Ganglia ?
A collection of nuclei (a group of cell bodies)
What are the Basal Ganglia important for ?
Controlling movement, reward systems
Lesions in the basal ganglia can cause disorders such as Parkinson’s and Huntington’s
What are the 3 parts of the basal ganglia ?
Caudate nucleus
Putamen
Globus pallidus
What are the 5 things included in the limbic system ?
Limbic cortex
hippocampus
amygdala
fornix
mammillary bodies
What is the limbic system important for ?
Emotion
Learning
Memory
feel related behaviour
emotional memory
What is the hippocampus important for ?
Consolidating memory
It is located in the temporal lobe
What is the diencephalon ?
The second division of the forebrain (prosencephalon)
What is the thalamus ?
Located in the diencephalon
Inner chamber
Two lobes separated by massa intermedia
Receives info from and sends info to the cortex
What are the 3 nuclei that the thalamus is divided into ?
Lateral geniculate - receives from retina, to visual cortex
Medial geniculate - receives from midbrain, to auditory cortex
Ventrolateral
What is the hypothalamus ?
Located in the diencephalon
Important for physiological processes (PNS)
Connected to the pituitary gland
What is the mesencephalon ?
The midbrain
What is the tectum ?
In the mesencephalon
Superior colliculi
Inferior colliculi
What is the tegmentum ?
In the mesencephalon
Reticular formation
Periaqueductal grey matter
Red nucleus
Substantia nigra ‘black substance’
What is the rhombencephalon ?
The hindbrain
What is the metencephalon ?
In the hindbrain
Contains the pons - sleep and arousal, relay info from cortex to cerebellum
Contains the cerebellum - modify movement so it is controlled and smooth
What is the myelencephalon ?
In the midbrain
Contains the medulla oblongata - regulates cardiovascular system, respiration, skeletal muscles
Wat are the subdivisions of the forebrain (prosencephalon) ?
Telencephalon - end brain
(cerebral cortex, basal ganglia, limbic system)
Diencephalon - interbrain
(thalamus, hypothalamus)
What are the principle structures of the midbrain (mesencephalon) ?
Tectum and Tegmentum
What are the subdivision of the hindbrain (rhombencephalon) ?
Metencephalon - after brain
(cerebellum, pons)
Myelencephalon - narrow brain
(medulla oblongata)
What are the 3 types of neurons and their roles ?
Sensory neurons - gets info from the body
Interneurons - link sensory and motor neurons
Motor neurons - take info yo the body and control muscle contractions
What are neurons ?
They do all of the information processing and information transmitting
Many different types of neurons
86 billion neurons
What is the structure of the neuron ?
Soma - cell body containing nucleus
Dendrites - receive messages and connect to other neurons
Axon - carries info from soma to terminal buttons
Myelin Sheath - wraps around the axon
Terminal buttons - at the end of axon branches
What are the 3 glia cells ?
Astrocytes - structural support and provide nutrients, surrounding the synapse
Oligodendrocytes - produce myelin sheath
Microglia - clear away dead neurons
What is the cell membrane ?
Covers all cells
Two layers of phospholipid molecules
Tails point in and heads point out
Intracellular fluid inside the cells
The ion channel spans the membrane
What are the two types of ions ?
Cations - positively charged
Anions - negatively charged
What is the intracellular fluid ?
Fluid containing potassium ions (K+) and anions (A-)
What is the extracellular fluid ?
Fluid containing sodium (Na+) and chloride (Cl-) ions
What is the membrane potential and how is it balanced ?
The difference in electrical potential inside and outside the cell
Balanced by diffusion and electrostatic pressure
What do organic anions A- do ?
Concentrate inside the cell
Cannot cross the membrane
What do potassium ions K+ do ?
Concentrate inside the cell
Want to diffuse out
Attracted to the inside of the cell as it is negative
The forces balance so K+ doesn’t move
What do chloride ions Cl- do ?
Concentrate outside the cell
Want to diffuse in
Repelled from the inside as it is negative
Forces balance so Cl- doesn’t move
What do sodium ions Na+ do ?
Concentrate outside the cell
Want to diffuse in
Attracted to the inside as it is negative
Na+ is forced into the cell
Kept controlled by sodium-potassium pumps
What is the resting potential of a neuron ?
-70mV
The inside is negative
The outside is positive
What is action potential ?
Rapid change in the membrane potential
It is an all or none process and it stays the same size throughout transmission
What is depolarization and hyperpolarization ?
Depolarization - decrease from normal resting potential (brings membrane closer to 0)
Hyperpolarization - increases relative to resting potential (more negative)
Threshold of excitation is -40
What is propagation ?
How the action potential is transmitted down the axon
Acts like a chain of dominos
Entry of sodium ions results in it being regenerated down the axon
What are the benefits of saltatory conduction ?
Fast conduction
More energy efficient
What is synaptic transmission ?
A chemical process of neurons sending messages
Neurotransmitters are released from one neuron and attach to another neuron
This initiates a reaction that ultimately results in postsynaptic potentials
What is the synapse ?
The junction between two neurons
Synaptic vesicles are filled with neurotransmitters
Synaptic cleft is the gap between two membranes
Synaptic cleft is 20 nanometres
What is the process of synaptic transmission ?
Ca channels open and Ca2+ enters
Vesicles fuse with membrane and pores open
Release of neurotransmitters
They diffuse and bind to postsynaptic membrane
Postsynaptic channel opens
Ions flow resulting in PSP
What causes excitatory and inhibitory postsynaptic potential ?
Excitatory - depolarization e.g. Na+
Inhibitory - hyperpolarization
What is an ionotropic receptor ?
Contains a binding site and an ion channel
This opens when molecule attaches to binding site
What is a metabotropic receptor ?
Contains a binding site
Initiates a chain reaction that eventually opens ion channels
Requires energy
PSP’s slower than those produced by ionotropic receptors
What is termination ?
Some neurotransmitters are left in the cleft and the process of removing these is termination
What is reuptake ?
A method of termination
The neurotransmitter is taken back by the presynaptic terminal via transporter molecules
What is enzyme deactivation/degradation ?
A method of termination
Transmitter is broken down by enzyme
e.g. acetylcholinesterase breaks down ach into choline and acetic acid
What does excitatory mean ?
Increases the likelihood of a neuron firing and produces action potential
What does inhibitory mean ?
Decreases the likelihood of a neuron firing
What is integration ?
The summation of PSPs in control of neurons firing
When summed, the hillock reaches threshold of excitation action potential is triggers in axon
What are 3 main neurotransmitters ?
Acetylcholine (Ach) - found at neuromuscular junctions and cause contractions
Dopamine - motor control, reward, addiction
Serotonin - regulation of mood, eating, sleeping
What is an antagonist ?
A drug that blocks neurotransmitters
e.g. botox blocks the release of acetylcholine and prevents muscle contraction
What is an agonist ?
A drug that mimics a neurotransmitter and enhances synapse function
e.g. muscarine imitates acetylcholine
What is a stroke ?
Impaired blood supply to the brain and results in behavioural deficits
Such as language production (Broca’s area) and contralateral paralysis
What is Alzheimer’s disease ?
Affects the temporal lobe (hippocampus) leading to memory impairment - spatial and episodic memory
What is Parkinson’s disease ?
Moto disorder due to degeneration of substantia nigra neurons in the brain
What is the case study of ‘tan’ ?
Man who had a stroke and damaged his motor cortex could only produce the word ‘tan’ but could still comprehend speech
What is the case study of Phineas Gage ?
Man who had an iron bar explode through his prefrontal cortex and resulted in his personality completely changing
What is the case study of HM ?
Man who suffered from epilepsy had surgery on his medial temporal lobe (hippocampus)
Resulted in memory impairments such as declarative and spatial memory but other cognitive and memory functions were unaffected