BIopsychology Flashcards
1
Q
What is Charles Darwin’s theory of evolution? Give an example.
A
Organisms that are better suited (able to adapt and adjust to their environment) for their environment will survive and reproduce while those that are poorly suited for their environment will die off.
Example: species of birds: Each species has adapted to different environments, primarily through variations in their beak shapes and sizes - allowing them to better reach for their food source.
2
Q
Give an example of human genetics supporting Darwin’s theory.
A
Example: Sickle cell anemia
- A genetic condition in which red blood cells take on a crescent-like shape affecting how they function.
- Causes many people to die at an early age but it is still common among people of African descent.
- Carriers of only one copy of the sickle cell gene are thought to be immune from malaria, a deadly disease which is common in Africa. HOWEVER, FULL BLOWN SICKLE-CELL ANEMIA, WITH TWO COPIED OF THE SICKE-CELL GENE, DOES NOT PROVIDE IMMUNITY.
- In this example, carrying the gene makes a person better suited for their environment. This is why certain genetic diseases that cause people to die not been removed from human genetics.
BOOK: 2 soeurs africaines, one carried the gene of sickle-cell disease ( HAS ONE COPY OF THE SICKLE-CELL DISEASE, BUT NOT THE FULL-BLOWN SICKLE-CELL ANEMIA, they still experience symptoms tho) and the other no. Both catch malaria. The one that had the gene is protected and the other dies two weeks later. This is a great example of how carrying a certain gene can make a person better suited for their environment. While does who are not adapted to their environment might just die off.
keep in mind: en afrique sa mutation is beneficial, aux us pas tant, she might pass it on to her descendants but it will not be beneficial in any way.
3
Q
GENES (NATURE/BIOLOGY) AND THE ENVIRONMENT (NURTURE)
(va voir l’image diapo 5 if any doubt)
What is a gene?
A
Genes are segments of your DNA, which give you physical characteristics that make you unique (they are found in chromosomes)
4
Q
GENES (NATURE/BIOLOGY) AND THE ENVIRONMENT (NURTURE)
What are chromosomes?
A
Chromosomes carry DNA in cells. DNA takes the form of a double-helix configuration.
5
Q
GENES (NATURE/BIOLOGY) AND THE ENVIRONMENT (NURTURE)
What is DNA?
A
DNA is responsible for building and maintaining your human structure.
6
Q
GENES (NATURE/BIOLOGY) AND THE ENVIRONMENT (NURTURE)
What is heritability? Give an example.
A
Measure of the variability of behavioural traits among individuals that can be accounted for by genetic factors.
À quel point un trait est héréditaire vs environnementale.
FOR EXAMPLE: if a trait like intelligence has high heritability, it means that a significant portion of the variation in intelligence levels among people is due to genetic differences rather than upbringing (how you were raised) or life experiences.
7
Q
What is the degree of relatedness?
A
The probability that a gene in one individual is identical-by-descent (inherited by a common ancestor) to a gene in another individual
EXAMPLE: monozygotic (division d’un ovule fécondé par un spermatozoïde) versus dizygotic twins (Les premiers proviennent de deux ovules fécondés par deux spermatozoïdes différents -> faux jumeaux)
8
Q
What is a genotype?
A
The term “genotype” refers to the genetic makeup of an organism; in other words, it describes an organism’s complete set of genes, so their unique sequence of DNA. It refers to how the alleles are paired.
EXAMPLE:
BB (blue eyes)
Bb (blue eyes)
bb (green eyes)
9
Q
What is a phenotype?
A
It describes an individual’s observable characteristics, such as hair color, skin color, height, and build. In other words, it’s the description of the genetic makeup (so how it looks: blue/green eyes…).
10
Q
What does a polygenic trait mean?
A
A trait that is controlled by more than just one gene. The majority of inheritable (traits passed down from parents) traits are polygenic.Polygenic traits typically show a range of variations, such as height or skin color, because they result from the combined effects of several different genes. This complexity can make these traits more variable and less predictable than traits controlled by a single gene.
11
Q
what is the difference between a gene and an allele?
A
Le gène est une très petite portion de chromosome. Comme les chromosomes (one from mom, one from dad), chaque gène est présent en double dans nos cellules (together they code a trait). Ces deux copies d’un même gène s’appellent des allèles (c’est une forme du gene, comme un des constituant en gros). Alleles can be dominant or recessive.
12
Q
What does it mean to possess a dominant allele
A
That it will always result in expression of that phenotype. The phenotype of a recessive allele will only be physically expressed if the person is homozygous for that allele, meaning they inherited a recessive allele from BOTH parents (aa).
13
Q
Heterozygous vs homozygous
A
Heterozygous - consisting of two different alleles (Aa).
Homozygous - consisting of two identical alleles (AA/aa).
14
Q
What are mutations?
A
sudden, permanent change in a gene.
Keep in mind: many mutations are harmful but some can also be beneficial (because, mutations created a genetic diversity -> mutation benefice can give an advantage to better adapts survive and reproduce : remember sickle-cells anemia example)
15
Q
What is the tool used to predict how genes will interact in the production of offspring?
A
A punnett square: The capital B represents the dominant allele, and the lowercase b represents the recessive allele. In the example of the cleft chin ( an inherited trait), where B is cleft chin (dominant allele), wherever a pair contains the dominant allele, B, you can expect a cleft chin phenotype. You can expect a smooth chin phenotype only when there are two copies of the recessive allele, bb.
Mom has a dominant and recessive allele, while dad two recessive allele, which means there is a 50% chance for their kid to have a cleft chin.
16
Q
GENE-ENVRIONMENT INTERACTION:
What is a range of reaction? Give an example.
A
Our genes create a limit of range for our potential in different traits, but where we actually end up within that range depends on our environment.
Example: a child who has a natural “connection/strength” with music, but has never nurtured that ability.
17
Q
GENE-ENVRIONMENT INTERACTION:
What is genetic-environmental correlation?
A
Our genes can shape the kind of environment we experience, and in turn, that environment can also influence how are genes are expressed. It’s a loop. For example, someone who is naturally athletic (genes) mights be drawn to sports (environmental), reinforcing their athletic abilities even further.
18
Q
GENE-ENVRIONMENT INTERACTION:
What are epigenetics?
A
It’s the study of gene-environment interactions such as how the same genotype leads to different phenotypes. Epigenetic changes are modifications to DNA that regulate whether genes are turned on or off.
A gene might be in our DNA, but not expressed, unless something triggers it (think schizophrenia. Also, something that was to be expressed can also be silenced.
19
Q
What are some early reflex action theories (5) ?
A
- Nerves and muscles compared to pipes and levers
- Animal spirits
- External object can illicit an
involuntary response - Reflex action did not require the mind
- Precursor to stimulus- response (S-R) behaviorism
20
Q
How did we get to these theories?
A
By experimenting on animals
21
Q
What is galvanism?
What was Luigi Galvani’s experiment and what was his impact on the development of early reflex action theories?
A
Galvanism is the process of contracting muscles with the use of electrical current. He believed that that electricity was created within the animal itself, he called it “animal electricity”
His experiment:
Dead frog -> a static electrical charge carried through a scapel through the frog -> shocked the frog’s legs, making it move as if it was still alive (so he moved with no need of the brain).
He also tried another way:
Two metals (the hook and the iron wire ). The iron wire connects to the frog’s exposed nerve , stimulating the muscles and causing them to contract.
Conclusions:
* Nerve impulses were electrical in nature
*Galvanic skin conductance
22
Q
What was the work of Giovanni Aldini (Galvani’s nephew).
A
*He expanded on his uncle’s work, focusing on the effects of electrical currents on dead animals and humans.
*Public demonstration of the electro-stimulation technique of deceased limbs was performed on the executed criminal George Forster at Newgate in London in 1803:
He connected wires from a voltaic pile (the early version of a battery) to various parts of Foster’s body, including face and limbs (arms or legs). The electric shocks caused his jaw to quieter, face muscles contracted and one ey opened, Right hand was raised and clenched and the legs and tights were in motion.
23
Q
Now, how does the electricity get through the body?
A
Neurons
24
Q
What is the Golgi staining method?
A
It’s a technique to make the structure of neutrons visible under a microscope.
25
What did Santiago Ramón y Cajal discover?
* Santiago Ramón y Cajal
used a Golgi stain to highlight the appearance of neurons.
* Each neuron composed of a body with many threads extending outward toward other neurons.
* Threads of each neuron do not actually touch other neurons (the synapse)
*** His observations led to understanding how neurone communicate with each other.
26
What are the origin of Behaviour?
Neurons.
27
What are the two main types of cells that make up the nervous system?
* Glial cells :
They play a supportive role to neurons. In fact, they provide scaffolding on which the nervous system is built, help neurons line up closely with each other to allow neuronal communication, provide insulation to neurons, transport nutrients and waste products and mediate immune responses.
* Neurons:
They generate and propagate electrical and chemical signals.
28
What characterizes the neurone's cell membrane.
It's semi-permeable membrane. Which means by its small pores that act as channels, it allows small electrically charged ions to flow in and out of cells, while stopping larger or highly charged molecules.
29
What are the two stages referred to as electrochemical action?
1. Conduction: internal flow of electrical signal(information) within a neutron.
2. Transmission: The process of sending electrical signal (information) from one neutron to another across a synapse.
SO we can say that there is communication of information within and between neurons.
30
What is the role of the cell body?
Coordinates information-processing tasks (so processes and forms a cohesive understanding) and keeps the cell alive
31
What is the dendrite's role?
Receives information from other neurons and relays it to the cell body
32
What is the axon's role?
Transmits information to other neurons, muscles, or glands
33
What is the synapse?
* The space between the terminal button of one neuron and the dendrite of another neuron
* Notice that neurons do not actually touch one another: There is a small synaptic space between them across where information is transmitted.
34
ELECTRICAL SIGNALLING: CONDUCTION INFORMATION WITHIN A NEURON
Do neurons have a natural electrical charge which changes as information is passed?
Yes.
35
What is the resting potential?
Difference in electric charge between the inside and outside of a neuron’s cell membrane when the cell is in a non-excited state. It's a state of readiness (being ready or prepared to fire the action potential, so to send a signal)
In the resting state, sodium (Na+) is at higher concentrations outside the cell since it is kept out (the channel is closed). On the other hand, K+ molecules flow freely across the cell membrane. So [Na+] is higher on the outside of the cell than on the inside. While [k+] is higher inside the cell rather Than outside. This creates a difference in electric charge between the inside and outside of a neuron's cell membrane. This means that the inside of the cell is approximatively 70 millivolts less positive than the outside.
So resting potential: - 70 mv, this is the potential energy that will be used to generate the action potential.
36
What are ion channels?
They are channels for each ion (Na+, k+...). As ions move across the channels, they cause the membrane's potential to move away from its resting potential.
37
What is the threshold of excitation?
It’s the start of depolarization stade (goes from -70 to 40, when the action potential is reached), which implies the change of the membrane's potential from negative to positive.
This is how it happens: From this resting potential state, the neuron receives a signal and its state changes abruptly (Figure 3.11). When a neuron receives signals at the dendrites—due to neurotransmitters from an adjacent neuron binding to its receptors—small pores, or gates, open on the neuronal membrane, allowing Na+ ions, propelled by both charge and concentration differences, to move into the cell. With this influx of positive ions, the internal charge of the cell becomes more positive. If that charge reaches a certain level, called the threshold of excitation, the neuron becomes active and the action potential begins.
38
Why is the action potential and "all-or-none" phenomenon?
In simple terms, this means that an incoming signal from another neuron is either sufficient or insufficient to reach the threshold of excitation. There is no in-between, and there is no turning off an action potential once it starts.
Because it is all or none, the action potential is propagated at its full strength at every point along the axon. It does not fade away as it travels down the axon.
39
What is the action potential (influx nerveux) and how is it reached?
It's the electric signal that is conducted along a neuron’s axon to a synapse (it's the positive spike)
40
What is the repolarization state and how does it happen?
At the peak of the spike, the sodium gates close and the potassium gates open. As positively charged potassium ions leave, the cell quickly begins repolarization.
The depolarization state is like a reset button, preparing the neuron for the next signal.
41
What is the hyperpolarization state?
The cell membrane’s potential becomes slightly more negative than the resting potential, and then it levels off (thanks to an active chemical “pump”), returning to the resting potential.
The active chemical "pump"in the cell membrane, moves Na+ outside the axon and moves K+ inside the axon. This helps restore the original distribution of sodium and potassium. The neuron can now generate another action potential.
This drop, is also called a refractory period: this is when the neuron recovers. it's very rested and stimulation should not happen. In other words, the refractory period is the time following an action potential during which a new action potential cannot be initiated.
42
What factor determinate if a signal will pass along or not.
The strength of the signal received by the dendrites. If the stimulation is strong enough it will be transmitted along the axon.
43
What role does myelin and nodes of Ranvier play?
Saltatory conduction:
Action potential happens at the nodes of Ranvier.
The electrical signal moves down the axon with the impulses jumping in a leapfrog fashion between the Nodes of Ranvier. The Nodes of Ranvier are natural gaps in the myelin sheath. At each point, some of the sodium ions that enter the cell diffuse to the next section of the axon, raising the charge past the threshold of excitation and triggering a new influx of sodium ions ( like charging stations, allowing the signal to be strong as It moves down the axon) .
44
CHEMICAL SIGNALLING: Transmission between neurons.
Where does it happen and how does it happen?
It happens at the synaptic gap:
(1) The action potential travels down the axon and (2) stimulates the release of neurotransmitters from vesicles.
(3) The neurotransmitters are released into the synapse, where they float to bind with receptor sites on a dendrite of a postsynaptic (lui qui attrape les neurotransmetteurs) neuron, initiating a new action potential.
The neurotransmitters are cleared out of the synapse by (4) reuptake into the sending neuron, (5) being broken down by enzymes in the synapse, or (6) binding to auto receptors on the sending neuron.
Good to know:
each vesicle contains about 10,000 neurotransmitter molecules.
45
What is a presynaptic neuron?
The neuron releasing the neurotransmitters.
46
What are autoreceptors?
Signal to Stop: The binding sends a signal to the neuron that there’s enough neurotransmitter in the area, which often leads the neuron to reduce or stop releasing more of that neurotransmitter.
Detect Levels: Autoreceptors are on the surface of nerve cells and check how much of a neurotransmitter (the chemical messenger) is around.
Regulate Release: If there’s too much neurotransmitter, the autoreceptors signal the neuron to stop or slow down releasing more.
Maintain Balance: If there’s not enough, they don't send that signal, allowing the neuron to release more.
So, their main role is to help keep the right amount of neurotransmitter in the brain, making sure things don’t get too high or too low!
47
What happens to the neurotransmitters
in the synapse?
Each neurotransmitter will bind to the receptor of its type.
Example: dopamine with dopamine (different shapes for different molecules)
48
What is reuptake?
Once an action potential has occurred, excess neurotransmitters in the synapse either drift away, are broken down (by enzymes) or are reabsorbed.
Reuptake involves moving a neurotransmitter from the synapse back into the axon terminal from which it was released (repurposing)
49
What are 5 types of neurotransmitters?
Acetylcholine (Ach), Dopamine, Serotonin, Norepinephrine and Endorphins.
50
Functions and malfunctions of Acetylcholine.
Functions: enables muscle action, learning and memory.
How they affect behaviour: Increased arousal, enhanced cognition
Malfunctions:
With Alzheimer's, Ash producing neurons deteriorate.
51
Functions and malfunctions of dopamine.
Functions: Influences movement, learning, attention and emotion
How they affect behaviour: Increased pleasure and suppressed appetite.
Malfunctions:
High levels linked to schizophrenia
low levels linked to Parkinson’s Disease
52
Functions and malfunctions of serotonin.
Functions:
Affects mood, hunger, sleep arousal
How they affect behaviour:
Modulated mood and suppressed appetite
Malfunctions:
Low levels are linked to depression.
53
Functions and malfunctions of norepinephrine.
Functions:
Involved in Heart, intestines, alertness and arousal (Arousal is a state in which you feel excited or very alert, for example as a result of fear, stress, or anger)
How they affect behaviour:
Increased arousal and suppressed appetite.
Malfunctions:
Low levels depress mood
54
Functions and malfunctions of endorphins.
Functions:
Boosts mood, lessens pain
How they affect behaviour:
Decreased anxiety and decreased tension.
Malfunctions:
Artificial opiates (pain relief drugs like heroin, codeine, morphine...) cause brain to stop producing endorphins.
So getting off those drugs feels very unpleasant.
**Exercise is a good way to boost endorphines
55
How do drugs mimic neurotransmitters?
Drugs affect the nervous system by increasing, interfering with, or mimicking neurotransmitters.
56
What are the two types of drugs? Give an example for each.
*Agonists: Drugs that increase the action of a neurotransmitter by mimicking it at the receptor site.
EXAMPLE: Nicotine is considered an agonist drug because it binds to and activates certain receptors in the brain, specifically the nicotinic acetylcholine receptors. When nicotine attaches to these receptors, it mimics the action of the neurotransmitter acetylcholine, leading to increased neuronal activity.
* Antagonists: Drugs that block or impedes the normal activity of a neurotransmitter at the receptor.
EXAMPLE: Caffeine is considered an antagonist drug because it blocks the action of a specific neurotransmitter in the brain called ADENOSINE. Adenosine promotes relaxation and sleep by binding to its receptors. When caffeine enters the bloodstream, it activates autoreceptors so they inhibit release of adenosine neurotransmitter.
57
What are the two main parts of the nervous system?
▪ Peripheral Nervous System (PNS) : includes the nerves that run throughout the whole body.
▪ Central Nervous System (CNS): brain and spinal cord
58
What is the central nervous system responsible for?
Spinal reflexes: Simple pathways in the nervous system that rapidly generate muscle contractions
59
What were Charles Bell's views on the earlier experiments conducted on physiology? What was his discovery?
Charles Bell:
* Limitations of dissection of dead animals.
Discovery:
Motor function in the anterior root.
60
What were Francois Magendie's discoveries?
* Stimulation of anterior portion of spinal cord resulted in movement (motor neurons)
which means, the anterior root of the spinal cord carries motor signals from the CNS to the muscles leading to movement.
* Stimulation of posterior resulted in pain (sensory neurons)
61
Explain how sensory and motor neurons work.
SENSORY NEURONS
Sensory neurons carry informations from the body to the central nervous system.
These neurons enter the spinal cord through the dorsal portion (the dorsal root contains signals from sensory receptors (ex: skin, organs...) to the spinal cord.
These sensory signals are transmitted upwards to the brain for interpretation.
MOTOR NEURONS:
Carry commands from the CNS (brain and spinal cord) to the muscles and gland.
They exit the spinal cord via the anterior portion (contains axons of motor neurons that transmit signals to muscles).
The signal originate from motor areas in the brain or local reflex circuits whiten the spinal cord itself!!!!
62
How do reflexes work?
Sensory cells carry input from the receptor (afferent impulses) to a central interneuron, which makes contact with a motor neuron. The motor neuron carries efferent impulses to the effector, which produces the response.
63
How does this (the way reflexes work) differ to what Descartes said?
- No relation to the mind, you don't need it : he used to say that animals spirits (signal) reach the pineal gland (that was where the physical body and the non-physical mind would meet)
- Animal sprits, not just a tube the animal spirit is going in, it's nerves and there are two types of signals : sensory signal and motor signals both having their own path.
What he was correct in:
- There are sensory receptors (sense organs)
64
What are the four main sections the spinal cord divided into and what is the role of these parts?
From top to bottom:
Cervical nerves
Thoracic nerves
Lumbar nerves
Sacral nerves
Each section controls their part of the body.
65
What does it mean if damage is higher on the spinal cord?
It means greater impairment.
66
What is the surface of the brain covered in?
Gyri and sulky.
67
What divides the brain into left and right hemispheres?
A deep sulcus (furrow) called the longitudinal fissure.
68
What is lateralization?
Lateralization : concept that each hemisphere of the brain is associated with specialized functions on one side of the body in preference to the other.
The left hemisphere controls the right side of the body.
The right hemisphere controls the left side of the body.
69
What is the corpus callosum's role?
The corpus callosum connects the left and right hemispheres of the brain. It's what allows the sides to communicate to each other.
70
What are the four parts of the hindbrain (cerveau postérieur)?
What is the main role of the hind brain and what is the role of each part?
Hindbrain includes:
- Medulla
- Cerebellum
- Pons
- Reticular formation
Hindbrain is located on the back of the brain, (looks like an extension of the spinal cord), and its role is survival. If any damage is done on the hindbrain, it generally calls for death.
* Medulla, controls the automatic processes of the autonomic nervous system such as:
Heart rate
Circulation
Respiration
* Cerebellum (cervelet)
Fine motor skills
Proper sequence
Cerebellum is latin for "little brain", because it receives messages from muscles, tendons, joints and structures in our ear to control balance, coordination, movement and motor skills. This means the cerebellum is very important for procedural memory.
* Pons (meaning: bridge)
Relay between cerebellum & other brain structures (to the rest of the brain)
* Reticular formation (NOTE: part of hindbrain and midbrain)
Sleep
Wakefulness
Arousal
71
What are the two parts of the midbrain (cerveau moyen)?
What is the role of each part?
* Substantia Nigra:
dopamine production (main role); involved in control of movement.
* Ventral tegmental area (VTA) : dopamine production (main role), associated with mood, reward, and addiction.
* reticular formation extends into midbrain!!
72
What are the substructures parts of the fore brain? What is the main role of the forebrain.
Substructures
* Limbic system which includes the Hypothalamus, Amygdala, and Hippocampus (all three very well protected)
* Cerebral Cortex
The forebrain is crucial for us, but not in the sense if smug happens to it, it's gonna kill us, more in the sens that it helps us thrive.
73
What are the functions of the Hypothalamus and where is it located?
* Located below the thalamus
FUNCTIONS:
MAIN ROLE: homeostatis (the state of balance within all physical systems needed for a body to function properly and survive)
So:
▪ Regulates body temperature
▪ Helps govern endocrine system
▪ Houses “reward centers” (in the sense that it doesn't feel good to be off-balance (off homeostatis), so it feels good (rewarding) to bring our body back to balance (sex, food...)
▪ Part of it uses light cues to regulate sleep-wake cycles
▪ Controls maintenance functions, such as eating and drinking
▪ regulation of sexual motivation and behavior.
74
Where is the amygdala located and what are the functions linked to it?
▪ Located at the tip of each side of the hippocampus
FUNCTIONS:
▪ It is involved in our experience of emotion (emotional processes) and in tying emotional meaning to our memories (attaching significance to events).
▪ Fear (help us stay safe/alive)
▪punishment or reward
MAKE NOTE OF:
▪ lateralization in the amygdala:
LEFT SIDE: Positive and negative emotions
RIGHT SIDE: negative emotions
Why is it beneficial for us to pick up negative on both sides of the amygdala?
In order to stay safe.
75
What is the link between PTSD/CPTSD and the amygdala?
PTSD: Post-traumatic stress disorder
CPTSD: much more common sustained trauma over life ( abuse trauma, relationship trauma, self-esteem issues...)
Someone who suffers from ptsd or ptsd has an amygdala that works too much. (Remember amygdala is responsible for emotional processes and linking emotions to memories)
76
What are the three functions of the hippocampus?
▪ Creates new memories
▪ Integrates
memories into a network of knowledge
▪ Consolidates and stores memories
77
What are two other structures of the brain (apart from the hindbrain, the midbrain and the forebrain)? What are their roles?
BASAL GANGLIA: (basically allows the body to execute smooth movement)
* Directs intentional movement
* Receives input from the cerebral cortex
* Sends output to motor centers in the brainstem
THALAMUS: (It's the outer grey matter layer located in the center of the brain)
* Receives input from all the major senses except smell.
* Relays and filters information from the senses and transmits the information to the cerebral cortex.
BASICALLY, it decides on body movement.
***
Words definition:
INPUT: the signals received by the system
OUTPUTS: the signals sent from it (the thalamus)
78
What is the cerebral cortex?
Who is the specie with the biggest heads?
The cerebral cortex is the outermost layer of your brain. Its surface has many folds.
Humans are the species with the biggest heads.
79
What was the early research done in order to discover brain regions?
Phrenology.
80
What is phrenology? Who was the researcher?
Franz Joseph Gall:
- he dissected the brains of dead animals and people.
- nerve fibres connecting each side to the opposite side refers to structures like corpus callous which links the left and right hemispheres.
two major types of tissues in the brain: white matter (nerve fibres that connect different parts of the grey matter to each other) AND grey matter ( contains most of the brain's neurons (nerve cells))
* Phrenology:
- The magnitude of one’s faculties could be determined by examining the bumps and depressions on one’s skull.
- Shape of the person’s head revealed intelligence and emotional character
- Faculty Psychology (s the idea that the mind is separated into faculties or sections, and that each of these faculties is assigned to certain mental tasks.)
- Faculties of the mind act upon and transform sensory information
- Faculties do not exist to the same extent in all people
- If faculty is well developed
brain region will grow and a bump will be noticeable on skull
If underdeveloped will cause an indent.
81
How come phrenology was used as a tool for racism?
This pseudoscience suggested that certain physical characteristics correlated with specific racial or ethnic groups, reinforcing stereotypes and justifying discriminatory beliefs.
82
What is one limitation of phrenology?
Bumps are not always biological nor do they represent accurately the shape of the brain.
83
Is Phrenology still around?
No, it used to be very popular, but it has been proven wrong.
84
What is a psychograph?
An instrument that would measure what our abilities and our personality are. It measured the subject's head at 32 points . From those measurements they reported the person's supposed mental attributes on a five-point scale ranging from "deficient" to "very superior
85
What did Pierre Flourens do?
Extirpation: destroying parts of the brain to see the consequences.
In fact, he surgically removed different parts of the brains of animals (pigeons and rabbits in particular) to observe the effects on behaviour and bodily functions.
86
What did Pierre Flourens discover? (4)
* Ablation: Showed that the mind was in the brain and not in the heart
ABLATION: the surgical removal of body tissue.
***There was still that debate about the brain and the soul and stuff.
* Cerebellum controls higher mental processes (The cerebellum is primarily responsible for muscle control, including balance and movement. It also plays a role in other cognitive functions such as language processing and memory)
* Parts of the mid brain control visual and auditory reflexes (some of the animals were not able to see or hear anymore when those areas were taken away)
* Observed that in some cases the function that was lost to an ablation was regained later (neuroplasticity)
87
What are the 4 lobes?
▪ Occipital—visual information (visual cortex)
▪ Parietal—information about touch (sensory cortex),
▪ Temporal—hearing (auditory cortex), language (Wernicke’s area),
▪ Frontal—planning, judgment, memory, reasoning, abstract thinking, movement (motor cortex)
*** frontal lobe reaches maturity at around 25.
88
Where is the somatosensory cortex located? What is its role?
In the parietal lobe. It's essential for processing sensory information from across the body. (in other words, it assesseds the informations coming from our sensory organs)
89
Where is the motor cortex located ad what is its role?
In the frontal lobe. The motor cortex sends the message that directs the muscles.
90
What are association areas?
Parts of the cerebral cortex composed of neurons that receive inputs from multiples areas. These neurons help provide sense and meaning to information registered in the cortex. For example, interneurons. (lobes communicate with each other, they are not completely independent areas)
91
What are mirror neurons? ***btw, watch the video on mirror neurons***
- A category of neurons.
* Found in the frontal and parietal lobes and have been identified in other species in addition to humans
* Activated when an organism engages in a behaviour or observes another engaged in that behaviour (mirror mirrors affect emotions: we see someone crying, it affects us too)
* Are also more highly activated when observing action within a context
92
In what way do mirror neurons help us stay safe?
We pick up on cues. For example, if someone is angry, we feel it, which allow us to take the precautions needed. Also, we see people experience something, and decide if its safe for us to do so too or not.
93
What is brain plasticity?
* Brains change as a result of experience (allows healing or different areas of the brain to compensate. In fact, if one area is damaged, an other can compensate)
* Children’s brains are much more plastic than adults. (yea, keep in mind age, level of trauma/injury.... plays a role)
EXAMPLE:
* If language is disrupted in left hemisphere, right hemisphere may compensate.
94
What is the link between phantom limbs and cognitive remapping?
When someone looses a limb, the brain areas that used to receive signals from that limb are reassigned to respond to signals from nearby areas of the body. Those repurposed neurons mights still products the sensation of being touched on the missing limb. This is caused by cognitive remapping, a process where the brain is rewiring itself and rearranging sensory information to adjust to the changes in the body.
95
What is one way to reduce pain in people experiencing phantom limb sensations?
Place a mirror between limbs (the real one and the missing one) to create the illusion of two limbs when the person is looking at the mirror. Then, someone has to rub their real limb, while the person keeps looking at the mirror. The brain sense the touch on the phantom limb aswell.
96
Before modernity, what were two main ways to study the damaged brain?
- dissecting animals
- Case studies
97
How did Paul Broca discover the Broca's area?
- Posthumous (after one's death) examination of Mr. Leborgne's brain.
- Mr. Leborgne lost his speech.
- When he dies, Paul Broca dissected his brain and found a lesion (huge tutor) in the left hemisphere which, he concluded, had been responsible for Leborgne's loss of speech.
98
What is the Broca'a area responsible for?
For speech production (the ability to speak)
99
What are the two language centers in the brain?
The Broca's area and the Wernicke's area.
100
What is the role of the Wernicke's area?
Speech comprehension.
101
Why is it useful that language formation and comprehension is not in the same area of the brain?
Because if it touched that area it would wipe out communication completely. While this way, even if the Wernicke's area is touched, the person can still speak, just not in way that other people would be able to understand what they are saying.
102
What was Phineas Cage's case study?
He was working on a railroad -> explosion -> the iron rod entered his face and skull -> he survived but his personality seemed to change (ATTENTION: PERSONALITY IS NOT STORED IN THE FRONTAL LOBE, BUT SOME KEY PARTS THAT HELP MAKE THE PERSONALITY IS IN THERE).
Gage’s prefrontal cortex was severely damaged in the left hemisphere. The rod entered Gage’s face on the left side, passed behind his eye, and exited through the top of his skull, before landing about 80 feet away.
The frontal lobe (prefrontal cortex) is responsible for making us "act like adults". So, he began to gamble, he was a jerk to everyone, bad executive function (would not do things), couldn't keep a job....
103
There is a lateralization of the two hemispheres. Which one is more verbal and which one is more spatial?
* Left hemisphere more verbal
* Right hemisphere more spatial
104
What do the split-brain studies reveal?
Reveal that two hemispheres perform different functions and can work together seamlessly as long as corpus callosum is intact.
Go see image diapo 76.
105
What is the Peripheral Nervous System?
Connects the central nervous system to the body’s organs and muscles
INCLUDES:
▪ Autonomic nervous system (ANS)
▪ Somatic nervous system (skeletal nervous system)
106
What is the role of the somatic nervous system?
To control voluntary movements of skeletal muscles.
107
What is the role of the autonomic nervous system?
To control self-regulated action of internal organs and glands.
108
What are the two components of the automatic nervous system?
The sympathetic nervous system (arousing: fight or flight) includes also the state of freeze not only fight or flight.
The parasympathetic nervous system (calming: rest and restore).
AROUSING MEANS: : causing stimulation to a state of excitement.
EXAMPLES OF AROUSAL
dilated pupils : we perceive a threat, our pupils dilate to let more light get in, so to get more info
Inhibits digestion: digestion takes a lot of energy and energy is needed elsewhere rn (to escape or fight the threat)
Accelerated heartbeat....
constant stressor: traffic : body constantly in the fight or flight response.
pour example of calming, c littéralement le contraire.
109
How do we know about the brain? (3 ways)
* examining the functional changes in people with brain damage
* experimenting with the effects of damage on animal subjects,
* other less invasive techniques for viewing the brain (neuroimaging techniques)
110
Why is it important to study electrical activity in neurons?
To study the link between brain structures and behaviour.
111
What is the device used to record electrical activity in the brain?
An electroencephalograph.
112
What was the Hubel and Wiesel experiment?
Hubel and Wiesel were scientists who studied how the brain processes what we see. They placed tiny electrodes in the brains of anesthetized cats to look at the visual cortex, the part of the brain that handles vision. They found that certain brain cells, called feature detectors, respond to specific things we see, like lines or movements. Their discoveries helped us understand how we perceive images.
113
Why is brain imaging important?
To study structure (structural brain imaging shows underlying brain structure) and to watch the brain in action.
114
What are two ways to see brain brain activity in living participants?
By a PET scan or a Functional MRI.
115
What is a Pet scan?
Positron emission tomography (PET) scans create pictures of the living, active brain (Figure 3.27). An individual receiving a PET scan drinks or is injected with a mildly radioactive substance, called a tracer. Once in the bloodstream, the amount of tracer in any given region of the brain can be monitored. As a brain area becomes more active, more blood flows to that area. A computer monitors the movement of the tracer and creates a rough map of active and inactive areas of the brain during a given behavior. PET scans show little detail, are unable to pinpoint events precisely in time, and require that the brain be exposed to radiation; therefore, this technique has been replaced by the fMRI as an alternative diagnostic tool. However combined with CT, PET technology is still being used in certain contexts. For example, CT/PET scans allow better imaging of the activity of neurotransmitter receptors and open new avenues in schizophrenia research.
116
What is a functional MRI?
In magnetic resonance imaging (MRI), a person is placed inside a machine that generates a strong magnetic field. The magnetic field causes the hydrogen atoms in the body’s cells to move. When the magnetic field is turned off, the hydrogen atoms emit electromagnetic signals as they return to their original positions. Tissues of different densities give off different signals, which a computer interprets and displays on a monitor. Functional magnetic resonance imaging (fMRI) operates on the same principles, but it shows changes in brain activity over time by tracking blood flow and oxygen levels. The fMRI provides more detailed images of the brain’s structure, as well as better accuracy in time, than is possible in PET scans (Figure 3.28). With their high level of detail, MRI and fMRI are often used to compare the brains of healthy individuals to the brains of individuals diagnosed with psychological disorders. This comparison helps determine what structural and functional differences exist between these populations.
117
Is the relationship between particular patterns of behaviour and brain damage causal?
Not always. For example, hormones do a lot, if we ignore them, someone could be wrongly diagnosed with a mental disorder when in reality it's a biological issue (a hormonal problem).
118
What can Transcranial magnetic stimulation methods do? How?
It's a cheaper option in order to study effects of brain damage. :
Those methods can (ETHICALLY) mimic brain damage:
A coil is placed against the scalp, and it delivers magnetic pulses to the brain:
* Temporarily deactivates neurons in the cerebral cortex
* Can be combined with fMRI techniques
* Manipulation can provide causal explanations
Transcranial magnetic stimulation is a safe and effective treatment proven to help those who struggle with severe depression. It is particularly helpful for people with depression who have not experienced significant relief from antidepressant medications or have difficulty with side effects.
119
What is the Endocrine System and what are its main components? What are their roles? What is the role of the hypothalamus?
A series of glands that produce hormones to regulate normal body functions.
The hypothalamus is a small part of the brain that acts as a bridge between the nervous system and the endocrine system (which controls hormones). It helps regulate many body functions by controlling the pituitary gland, which releases hormones that affect other glands in the body. In simple terms, the hypothalamus helps manage communication between the brain and the hormone system.
Pituitary gland – serves as the MASTER gland, controlling the secretions of all other glands.
Thyroid – secretes Thyroxine which regulates growth, metabolism and appetite
Adrenal gland - secretes hormones involved in the stress response.
Gonad - secretes sex hormones, which are important for successful reproduction, and regulate sexual motivation and behavior.
Pancreas - secretes hormones that regulate blood sugar.
**remember, hypothalamus: homeostatis.
