Midterm deck (Brain & Behaviour, Smell, Perception) Flashcards
Biological Ψ / physiological Ψ / behavioral neuroscience -
study of physiological bases of behaviour, primarily focusing on the relationship b/w Ψ processes and underlying physiological events - the mind-body phenomenon
fn of the brain and the rest of the nervous system in activities recognized as characteristic of humans and other animals
about relationship b/w body & mind: “The two exist as aspects of the same entity, the mind being merely of the body’s functions” - says who?
Aristotle
Both the mind and the soul are spiritual entities existing separately from mechanical operations of the body -
Dualism, René Decart
Focusing on observable human & animal behaviours and their relationship to the nervous system -
behaviourism, John B. Watson
Mind & body are separate but their activities directly parallel each other -
Ψ parallelism theory, Gottfried Leibniz
Nervous system scheme
Prosencephalon (forebrain) is divided into:
and will develop into:
- telencephalon => cerebrum, cerebral hemispheres
- diencephalon => thalamus, epithalamus, hypothalamus
Mesencephalon (mid brain) will develop into (3):
mid brain - corpora quadrigemina, tegmentum, cerebral peduncles
Rhomencephalon (hind brain) is divided into:
and will develop into:
- metencephalon => pons, cerebellum
- myelencephalon => medulla oblongata
2 types of structures in PNS
- nerves - enclosed bundle of axons
- ganglion - ganglia (lumps that are attached to nerves and contain somas of neurons)
Neurons that carry info to the CNS -
afferent
Neurons that carry info from the CNS -
efferent
types of cells in NS (2):
- neurons (neu)
- neuroglia - non-neural cells that maintain homeostasis, form myelin, provide support & protection f/ neurons in CNS
Types of neurons (4):
- unipolar / pseudopolar: dendrite & axon from the same process
- bipolar: axon & single dendrite on the opposite ends of soma
- multipolar: 2/more dendrites, separate from axon
- anaxonic: axon can’t be distinguished from dendrites
Types of neuroglia (4 in CNS and 2 in PNS):
in CNS
- oligodendrocytes: produce myelin sheath (insulation to axons => electrical sygnals propagate more efficiently)
- astrocytes/astroglia: link neu to their blood supply + form blood-brain barrier (BBB); regulate external chemical environment of neu
- ependymal cells: creation & secretion of cerebrospinal fluid (CSF)
- microglia
in PNS:
- Schwann cells: myelination, phagocytic activity, clear cellular debris => regrowth of PNS neurons
- satellite cells: regulation of external chem environment
Why neuroglia occupy approximately the same space/volume as neu?
they are 10X smaller, but 10X more abundant
Barrier b/w the blood & the fluid that surround the cells of the brain
BBB (Blood-brain barrier)
where is BBB weaker and why?
area postrema of medulla oblongata; to initiate vomiting in case of toxins in the bloodstream
what can prevent withdrawal reflex?
inhibitory interneu
the most common synapse in NS -
axodendritic
other two are axoaxonic and axosomatic
Acetylcholine - neurotransmitter responsible f/ (4):
- voluntary muscle control
- parasympathetic NS
- attention
- alertness
Epinephrine, Norepinephrine are neurotransmitters responsible f/ (3):
- fight-or-flight responses
- wakefulness
- alertness
dopamine is a neurotransmitter responsible f/ (2):
- smooth movements
- postural stability
serotonin is a neurotransmitter responsible f/ (4):
- mood
- sleep
- eating
- dreaming
GABA is a neurotransmitter responsible f/:
brain “stabilization”
endorphins are neurotransmitters that are like what?
natural painkillers
2 parts of NS and their function
- CNS (brain + spinal chord) - processing info gathered from the nerves, transmitting instruction to the body
- PNS (all other nerve pathways outside CNS) - gathering ingo, reflexes
Forebrain consists of (3):
- cerebrum
- thalamus
- hyputhalamus
(limbic system)
Midbrain consists of (2):
- tegtum
- tegmentum
Hindbrain consists of (3):
- cerebellum
- pons
- medulla
Brainstem =
midbrain + pons + medulla
Frontal lobe is responsible f/ (6):
- reasoning
- planning
- speech
- mvmnts
- emotions
- problem solving
Parietal lobe is responsible f/ (3):
- control of mvmnt
- orientation
- recognition
Occipital lobe is responsible f/ (2):
- visual perception processing
Temporal lobe is responsible f/ (4):
- control of perception
- recognition of auditory stimuli
- memory
- speech
right hemisphere -
creativity
left hemisphere
logical abilities
bundle of axons that connects two hemispheres -
corpus callosum
Limbic system consists of (4):
- thalamus
- hypothalamus
- amygdala
- hippocampus
thalamus fn in limbic system:
relay station f/ sensory info (except f/ olfaction)
hypothalamus fns (5):
- regulation of homeostasis
- emotion
- thirst
- hunger
- control of autonomic NS
amygdala what is it and fn
part of telencephalon, located in temporal lobe, involved in memory emotion & fear
hippocampus (2):
- learning
- memory (short-term to long-term)
Brain stem is responsible f/
basic vital life functions (breathing, heart beat, blood pressure)
Midbrain (tectum over tegmentum)’s functions (4):
- vision
- hearing
- eye mvmnt
- body mvmnt
Charge and contents of intracellular fluid
negative, contains A-, K+
Charge and contents of extracellular fluid
positive, Na+, Cl-
what allows cells generate and transmit impulses?
(transporter in the membrane)
Na-K transporter in the cell membrane
stored charge (source of electrical E) -
membrane potential
resting potential - neuron is
steady, ready f/ action
positive charge applied to the inside of membrane -
depolarization
how long is depolarization process?
2 ms
voltage lvl that triggers action potential (AP) -
threshold of excitation
permeability of the membrane to a particular ion at any given moment is determined by:
the # of ion channels that are open
description of mvmnt of ions through the membrane during the AP (6 steps):
Threshold of ecxitation: over -70 mV
1. Na+ channels open, Na+ begins to enter the cell
2. K+ channels open, K+ begins to leave cell
3. Na+ channels become refractory at ~+35 mV => no more Na+ enters cell
4. K+ continues to leave cell, causes membrane potential to return to resting lvl
5. K+ channels close, Na+ channels reset
6. Extra K+ outside diffuses anyway
which ion is responsible f/ cell’s depolarization?
Na+
why does AP only travel in one direction?
Due to Na-channels refractory period
AP either occurs fully (w/ the same strength and consistency from origin to synaptic button) or does not occur at all
All-or-none law
saltatory conduction -
due to myelination of axons AP occur only @ unmyelinated parts of the axon (Nodes of Ranvier)
Advantages of saltatory conduction
- economic in terms of E
- speed
We sense the external world by means of small faint copies of objects that are transmitted from the objects to us
Democritus, 5 century BC
Stimuli reaching our sense organs produce responses in sensory nerves => diff nerves evoke diff types of sensations
Johannes Muller, 1825
how smell is coded:
aromatic chemical substances => nasal cavity => olfactory epithelium (roof of nasal cavity) => olfactory sensory neu => AP => olfactory bulb (glomerulus, mitral cells) => olfactory cortex (1. conscious identification - frontal lobe; 2. emotional response - limbic system)
overwhelming sensitivity to smells: what is it and what is it caused by (4)?
hyperosmia
may be caused by:
- pregnancy
- migraines
- neurological conditions
- autoimmune diseases
conscious perception of smell -
frontal cortex
motivational and emotional aspects of smell -
hypothalamus, amygdala
odor memory -
hippocampus
process that allows to give meaning to the info provided by our senses -
perception
what we is in our … not our …
what we is in our mind, not our eyes
illusion -
effect of misinterpreting data
3 types of illusion:
- geometric: image displayed appears to be distorted (Ponzo illusion where top line looks longer that the bottom, even though they are exactly the same)
- ambiguous figures: image can be seen in more than one way (Necker Cube, dress test, bunny/duck - depending on expectations, context)
- fictitious percepts: seeing smth that is not actually there (unfinished triangle - white triangle)
Visual constancies -
smth that allows us to see things as remaining the same even when their physical characteristics are constantly changing;
2 types of visual constancies:
- shape constancy - ability to perceive the shape of an object as constant even if it changes through mvmnt (open door is still rectangular)
- color constancy - ability to perceive the color of an object as constant even if it changes with lightning
perceptual sense & perceptions are affected by (6):
- context
- expectations
- culture
- previous experience
- emotions
- motivations
Gestalt rules (4)
form perception - figure-ground relationship: how we organize & simplify whatever we’re looking at
- grouping (black&white dots are seen as “lines”)
- similarity (things which share similar characteristics - shape, size, color, texture, value of orientation - seen as belonging together; ex - statue of liberty = triangles)
- continuity (tendency to organize visual elements into unified wholes; ex - WWF emblem)
- connectedness (ex - olympic rings, which are not connected)
depth perception -
ability of our eyes & brain to add a 3rd dimension / depth to everything we see, with the help of depth ques
depth cues (5):
- linear perspective - parallel lines appear to converge & come together at a distant point
- two heights in plane - if an image is higher to the eye it is often seen as being further away than the objects to the lower (ships)
- relative size - when we expect objects to be the same size and they are not we assume that they are further away (asian women)
- superimposition/overlap - when we can’t see the whole object we assume that there is smth in front of it => the object is further away (woman w/ house and car)
- texture gradients - we can see the details of objects that are close but the detail fades the further away it is
The constructivists theory of perception:
we construct our perception based not only on what we see but also on our past experiences = top-down processing
perceptual set
notion of perceiving smth based on expectation
2 examples demonstrating perceptual set in processing:
- expectations (jumbled up words)
- motivations (coloured words)
criticisms to constructivists’ top-down theory (3):
- why do diff ppl perceive things the same way?
- if perception requires experience, then how do we explain a newborn’s ability to perceive the world?
- the effects of illusions - why do we fall for it every time if we use our experience to build perception?
nativists’ theory of perception:
perception is the result of bottom-up processing => it’s immediate and direct, we perceive the world as it is seen, not based on expectations, the role of mind is to simply analyze
action potentials -
messages that are sent through the axon from the body to the terminal button
