Chapter 2.1 - 2.2 Flashcards
1
Q
To understand how the mind works you must experiment borh:
A
Behavioural and physiological experiments
2
Q
What is physiological?
A
branch of biology that deals with the normal functions of living organisms and their parts.
3
Q
What is cognitive neuroscience?
A
Field concerned with studying the neural basis of cognition.
4
Q
The reasoning behind the conclusion in order to understand how the mind works to do both behavioural and physiological experiments
Is based on the idea of what?
A
Level of analysis
5
Q
What is level of analysis?
A
A topic can be understood by studying it at a number of different levels of a system.
each approach contributing its own dimension to our understanding
6
Q
Analogy of level of analysis
e.g buying a new car
A
- You can and should of course look at its performance on the road; how well does it accelerate, brake and take corners?
- On the other hand, you can also look at what is going on under its hood; are motor, breaking and steering mechanisms functioning okay and are they not affected too much by wear and tear?
- Indeed, you can look at an even deeper level, for example by finding out how well fuel enters the engine and how it is ignited.
- Clearly, considering the automobile from the different levels of driving the car, describing the motor and observing what happens inside a cylinder provides more information about cars than simply measuring the car’s performance.
7
Q
Applying the level of levels of analysis to cognition
e.g car
A
- Consider measuring behaviour to be compared to measure the car’s performance
- measuring the physiological processes behind the behaviour as comapred to what we learned by looking under the hood.
- Study what is happening under a car’s hood at different levels,
8
Q
Applying the level of levels of analysis to cognition
A
Can study the physiology of cognition at levels ranging from the whole brain to structures within the chrain, to chemicals that create electrical signals within these structures.
9
Q
Brain is static tissue
meaning
A
No moving parts like the heart
Doesn’t expand or contract (like lungs)
10
Q
What to look for when understanding the relation between the brain and mind and specifically to understand the physiological basis for everything we perceive?
necessary to look at?
A
Look within the brain and observe small units of neurons
11
Q
What are neurons?
A
Cell that is specialized to receive and transmit information in the nervous system.
Create and transmit information about what we experience and know.
12
Q
What was discovered in the 19th century?
A
The nature of electrical signals in the brain and the pathways over which they travelled began to discover
13
Q
How did people observe the structure of the brain in 19th century?
A
- 19th century anatomists applied special stains to the brain issue
- This increased the contrast between different types of tissues within the brain
14
Q
What happened when 19th century ataomists applied the special stain in the brain tissue and viewed this stained brain tissue under a microscope?
A
Saw a network that they called nerve net
Provided complex pathway for conducting signals uninterrupted through the network
15
Q
What is nerve net?
A
A network of continuously interconnected nerve fibres (as contrasted with neural networks, in which fibres are connected by synapses).
16
Q
Diagram of nerve net theory and image of neurons
A
17
Q
What one reason for descriving the microstructure of the brain as a continuously interconnected network?
A
Staining techniques and microscope used during 19th century could not resolve small details, without these details, the nerve net appeared to be continuous
18
Q
What did Camillo Golgi do in 1870?
Italian anatomist
A
- Developed a staining technique which created photo shown below(2.2b)
- With this staining technique, named after its inventor, less than one per cent of the cells were stained, so they stood out from the rest of the tissue. Also, the cells that were stained were stained completely, so it was possible to see their structure.
*
19
Q
What was Camillo Golgi’s staining technique called
A
Golgi staining technique or called black reaction after the stain’s colour
20
Q
What did Ramon y Cajalf did?
Spanish physiologists
A
- Used Golgi staining technique in newborn animals to closely investigate the nature of the nerve net
21
Q
Why was Ramon y Cajal’s decision to use newborn animals clever?
A
Density of cells in newborn brain is small compared to the density in the adult brain
22
Q
What did Ramon y Cajal discover?
A
- This property of the newborn brain, combined with the fact that the Golgi stain affects less than one per cent of the neurons, made it possible to clearly see that the nerve net was not continuous, but was instead made up of individual units connected together (Kandel, 2006).
- The discovery that individual units called neurons were the basic building blocks of the brain was the centrepiece of the neuron doctrine
23
Q
What is neuron doctrine?
A
The idea that individual cells called neurons transmit signals in the nervous system, and that these cells are not continuous with other cells as proposed by nerve net theory.
24
Q
Basic parts of neuron diagram + synapse
A
25
What is the cell body?
Metabolic centre of the neuron
Contains mechanisms to keep the cell alive
Part of a cell that contains mechanisms that keep the cell alive. In some neurons, the cell body and the dendrites associated with it receive information from other neurons.
26
What is the function of dendrites?
receive signals from other neurons.
Structures that branch out from the cell body to receive electrical signals from other neurons.
27
Where does dendrites branch out from?
Cell body
28
What are axons also known as?
Nerve fibres
29
What are axons?
Part of the neuron that transmits signals from the cell body to the synapse at the end of the axon.
are usually long processes that transmit signals to other neurons.
30
What does this figure show?
shows a neuron with a receptor that receives stimuli from the environment—pressure, in this example. Thus, the neuron has a receiving end and a transmitting end, and its role is to transmit signals.
31
Important conclusions Cajall came to about neurons?
1. There is a small gap between the end of a neuron’s axon and the dendrites or cell body of another neuron. This gap is called a synapse .
2. Neurons are not connected indiscriminately ( in a random manner) to other neurons, but form connections only to specific neurons. This forms groups of interconnected neurons, which together form neural circuits.
3. In addition to neurons in the brain, there are also neurons that are specialized to pick up information from the environment, such as the neurons in the eye, ear and skin
1. Neurons are called receptors
32
Analogy of a synpase
In the highway analogy, a synapse may symbolize a crossing with traffic lights, providing an opportunity to manage the flow of cars, to reduce their speed, and to distribute them over different routes.
33
What is a synapse?
Space between the end of an axon and the cell body or dendrite of the next axon.
34
What is a neural circuits?
Group of interconnected neurons that are responsible for neural processing.
35
What are the receptors?
Specialized neural structures that respond to environmental stimuli such as light, mechanical stimulation or chemical stimuli.
36
Receptors synapse close up
37
Contribution of Cajalf
* Separate neurosn communicate with other neurons to form neural circuits enormous leap forward in understanding how the nervous system operates
* The concepts introduced by Cajal—individual neurons, synapses and neural circuits—are basic principles that are still used today to explain how the brain brings about certain cognitive functions, such as perception, language and memory.
* These discoveries earned Cajal the Nobel Prize in 1906, and currently, he is recognized as “the person who made the cellular study of mental life possible” (Kandel, 2006, p. 61).
38
What did Cajal miss after describing the development of individual neurons and how they are related to other neurons and transmitted signals?
Determining the exact nature of these signals had to await the development of electronic amplifiers that were powerful enough o make the extremely small electrical signals generated by the neuron visbile.
39
Whast was Edgar Adrian in 1920s able to record?
electrical signals from single sensory neurons, an achievement for which he too was awarded the Nobel Prize.
40
When an axon/nerve fibre is at rest the meter records a difference in potential between the tips of the two electrodes of how much millivolts?
-70 millivolts
41
Millivolt is 1/1000 of what?
A volt
42
-70 millivolts is the value stays the same as long as there are no signals in the neuron is called what?
Resting potential
Neuron has a charge that is 70 mv more negative than the outside and this difference continues as long as the neuron is at rest
43
Definition of resting potential
Difference in charge between the inside and outside of a nerve fibre when the fibre is at rest (no other electrical signals are present).
44
Diagram of typical set up recording from a single neuron
45
How did Adiran (1928,1932) record electrical signals from a single neuron?
Using microelectrodes
46
What are microelectrodes?
Small wires that are used to record electrical signals from single neurons
small shafts of hollow glass filled with a conductive salt solution that can pick up electrical signals at the electrode tip and conduct these signals back to a recording device.
47
What two types of electrodes needed from this setup to record a single neuron?
* Recording electrode
* Reference electrode
48
What type of electrodes do modern psychologists use?
Metal microelectrodes
49
Where is recording electrode located?
When used to study neural functioning, a very thin glass or metal probe that can pick up electrical signals from single neurons.'
Recroding tip inside the neuron
50
Asummption of recording electrode
In practice, most recordings are achieved with the tip of the electrode positioned just outside the neuron because it is technically difficult to insert electrodes into the neuron, especially if it is small. However, if the electrode tip is close enough to the neuron, the electrode can pick up the signals generated by the neuron.
51
Where is reference electrode located?
* Used in conjunction with a recording electrode to measure the difference in charge between the two.
* Reference electrodes are generally placed where the electrical signal remains constant, so any change in charge between the recording and reference electrodes reflects events happening near the tip of the recording electrode
* some distance away so it is not affected by the electrical signals..
52
The difference in charge between recording and referencing electrodes is fed into computer and what?
Displayed on the computer screen
53
Where can single cell recording be used?
* Invavise method and used in animals like mice, cats and monkeys
* Possible to perform such recordings on humans during brain suregrey
* These recordings taught us a lot abut how concepts are represented in the brain
* But also how attention, memory, anticipate and decision making
* Avdantage: Provides very precise information about when and where neural activity happens
54
What does figure 2.5b show?
* Neuron's receptor is stimulated by a nerve impulse is transmitted down the axon
* As impulse passes the recording electrode, charge inside the fibre reverses course and starts becoming negative again (figure 2.c) until it returns to resting potential (figure 2.5d) - this is called action potential lasts 1 millisecond
55
What is a nerve impulse?
An electrical response that is propagated down the length of an axon (nerve fibre). Also called an Action potential.
56
What is action potential?
Propagated electrical potential responsible for transmitting neural information and for communication between neurons. Action potentials typically travel down a neuron’s axon.
57
What is a millisecond?
1/1000 second
58
What does figure 2.6 show?
* Action potential on a compressed time scale
* Each vertical line represents action potential, series of line indicate a number of action potential passed electrode (2.6a)
* One action potential expanded on a time scale. There are other electrical signals in a nervous system but we will focus on action potential (2.6b)
59
What is the second discovery that Adrian made apart from recording action potentials from single neurons
* Each action potential travels all the way down the axon without changing its height or shape
* Property makes action potentials ideal for sending signals over a distance, because it means that once an action potential is started at one axon, the signal will be the same size when ti reaches the end
* No matter how long the distance is
* Therefore, no loss of info or energy
60
When action potential reach the synapse at the end of axon a chemical called what is released?
Neurotransmitter
61
What is a neurotransmitter?
Chemical that is released at the synapse in response to incoming action potentials.
62
What does this neurotransmitter make it possible?
signal to be transmitted across the gap that separates the end of the axon from the dendrite or cell body of another neuron
63
Synaptic transmission compared to action potential
* In contrast to action potentials, synaptic transmission is not an electrical transport of signals but a biochemical one, and thus follows different principles.
* In addition, as mentioned before in the highway and traffic light analogy, this is the moment at which “signals” can be changed and managed.
* For example, if a train of 10 impulses arrives at the synapse, the next, receiving neuron does not necessarily create another train of 10 impulses.
64
The reason why the receiving neuron most likely does not also create a train of 10 impulses is because it is dependent on
(2)
* what and how much information is carried through by means of the neurotransmitters (some information may get lost while other information is amplified)
* what and how much information it receives from other neurons that also make connections with this neuron.
65
Cognitive psychology main interest
* not in how neurons transmit signals, but in how these signals contribute to the operation of the mind.
* how signals are transmitted is compared to describing how the internet transmits electrical signals, without describing how the signals are transformed into words and pictures that people can understand. Indeed, it is important to go beyond simply describing nerve signals and to discover how these signals relate to stimuli in the environment and therefore to people’s experience
66
Imagine you want to study the relation between nerve firing and sensory experience
How do you so and what will you find?
* measuring how the firing of a neuron from a receptor in the skin changes as you apply more pressure to the skin.
* find is that the shape and height of the action potential will remain the same as you increase the pressure, but that the rate of nerve firing–that is, the number of action potentials that travel down the axon per second–will increase
67
What does this figure deduced?
* important connection between nerve firing and experience can be deduced.
* Namely, when nerve impulses are close together (high firing rate) the sensation is intense, and, in contrast, when nerve impulses are more separated from each other (low firing rate) then the sensation is correspondingly weak.
68
What does this simple experiment of finding out the relation between nerve firing and sensory experience suggest?
* electrical signals are representing the intensity of the stimulus, so the pressure that generates “crowded” electrical signals feels stronger than the pressure that generates signals separated by long intervals.
69
What does this simple experiment suggest about vision?
* Other experiments have demonstrated a similar principle for vision.
* Presenting high-intensity light generates a high rate of nerve firing and the light is perceived or “experienced” as being bright;
* presenting lower intensity light generates a lower rate of nerve firing and the light is perceived or “experienced” as being dimmer.
* Thus, the rate of neural firing is related to the intensity of stimulation, which, in turn, is related to the magnitude of an experience, such as feeling pressure on the skin or experiencing the brightness of a light.
70
We can extend this idea that there is a relationship between nerve firing and perceptual experience by finding out how
nerve impulses are involved in other aspects of cognition such as memory, language and thinking. The first step toward doing this is to consider the representational function of nerve impulses.
71
What is principle of neural representation state?
Everything a person experiences is based on representations in the person’s nervous system.
person experiences is based not on direct contact with stimuli, but on representations in the person’s nervous system
e.g although you may experience this book page as some sort of visual image that you can read, in your head it is really not more than a complicated pattern of firing neurons.
72
Why is the idea of representation in cognitive psychology so important?
because one approach to understanding cognition is to consider how our experiences are represented both in our mind (measured behaviourally) and in the brain (measured physiologically).
73
We will use perception as our example to discuss representation by neurons, keeping in mind that
principles that apply to perception also apply to other cognitions such as memory, language and thinking.
e.g idea that the magnitude of experience—our perception of a 100-watt light as brighter than a 40-watt bulb—is related to the rate of nerve firing, we can take the next step and ask, what about the quality of experience?
74
What does quality across senses refer to?
different experience associated with each of the senses
perceiving light for vision, sound for hearing, smells for olfaction, and so on.
75
Ask quality about a particular sense e.g
, such as shape, colour, or movement for vision, or sweetness, saltiness and bitterness for taste.
76
One way to answer of how action potential determine different qualities is to propose:
1 possibility
action potentials for each quality might look different.
However.
ruled out that possibility by determining that all action potentials have basically the same height and shape.
77
If all nerve impulses are basically the same, whether they are caused by seeing a red fire engine or by tasting something sweet, how can these impulses stand for different qualities?
begin answering this question by first considering single neurons and then moving on to groups of neurons. We focus on the visual system because vision is the most studied modality within this context.
78
Past research on how neural signalls represent things focused on:
how neurons fire to different sensory stimuli.
79
What did David Hubel and Thortsen Wisel started in 1960s?
series of experiments in which they presented visual stimuli to cats, as shown in Figure 2.8a, and determined which stimuli caused specific neurons to fire
80
What did David Hubel and Thortsen Wisel found in their experiment?
each neuron in the visual area of the cortex responded to a specific type of stimulation presented to a small area of the retina.
81
What does figure 2.8b show?
* shows some of the stimuli that caused different neurons in and near the visual cortex to fire
* They called these neurons feature detectors because they responded to specific stimulus features such as orientation, movement and length.
82
What are feature detectors?
Neurons that respond to specific visual features, such as orientation, size, or the more complex features that make up environmental stimuli.
83
This knowledge that neurons in the visual system fire to specific types of stimuli led to the idea that each of the thousands of neurons that fire when we look at a tree
e.g
fire to different features of the tree. Some neurons fire to the vertically oriented trunk, others to the variously oriented branches, and some to more complex combinations of a number of features.
84
The idea that the “tree” is represented by the combined response of many feature detectors is similar to the idea that a Lego house
e.g lego
onsists of a combination of specific Lego blocks with different shapes, colours and sizes.
85
Feature detectors are situated where?
visual cortex, which is the first place that electrical signals from the eye reach the brain.
86
For humans, and indeed all other mammals, the visual cortex is situated at where?
back of our head, the occipital lobe (the ‘magenta’ part
87
What has further research beyond visual cortex revealed about neurons
respond to more complex stimulus features (for example, geometrical shapes, hands, buildings or faces) or to a combination of simple stimulus features (for example, a left-tilted line that moves to the right).
neurons are situated in the cortex at the side of our head. This part of our brain is called the temporal lobe (this is the brownish part in Figure 1.12).
88
How are complex stimuli represented by the firing of neurons in the brain?
Where did the answer to this question emerge?
began to emerge in the laboratory of Charles Gross.
89
In early experiments, Gross and colleagues recorded activity from what?
* from single neurons in a monkey’s temporal lobe, on the side of the brain, while a variety of different stimuli were presented on a projection screen like the one in Figure 2.8a.
* Besides diagonally oriented bars, they also presented squares and circles, and some stimuli were light and some were dark.
90
Charles Gross lab study
The discovery that neurons in the temporal lobe respond to complex stimuli came a few days into one of their experiments by accident, how?
* when they had found a neuron that refused to respond to any of the standard stimuli (i.e., the bars, circles and squares). Nothing worked, until one of the experimenters pointed at something in the room, inadvertently casting a shadow of his hand on the screen. Suddenly the neuron started firing! This provided the hint that perhaps this neuron responds to a more complex shape like a “hand.”
* This unintended finding consequently inspired the experimenters to investigate what other stimuli could also cause this neuron to fire.
91
Charles Gross conclusion
* Great deal of testing, they determined that this neuron responded maximally to a hand-like shape with fingers pointing up (Figure 2.9)
* After expanding the types of stimuli presented and the place of recording, researchers also found some other neurons in the temporal lobe that responded best to faces, but didn’t respond to other types of complex stimuli like hands or buildings
92
Summary of results
(1)
neurons in the visual cortex respond to simple stimuli like oriented bars;
(2)
neurons in the temporal lobe respond to complex geometrical stimuli; and
(3)
neurons in another area of the temporal lobe respond to hand shapes or faces.
93
What does these results show:
## Footnote
(1)
neurons in the visual cortex respond to simple stimuli like oriented bars;
(2)
neurons in the temporal lobe respond to complex geometrical stimuli; and
(3)
neurons in another area of the temporal lobe respond to hand shapes or faces.
* neurons in the visual cortex that respond to relatively simple stimuli send their axons to higher levels of the visual system, where signals from many neurons combine and interact; neurons at this higher level, which respond to more complex stimuli such as geometrical objects, then send signals to higher areas, combining and interacting further and creating neurons that respond to even more complex stimuli such as faces.
* Progession from low to higher areas of brain is called hierarchical processing
94
What is hierarchical processing?
Processing that occurs in a progression from lower to higher areas of the brain
95
Qs of hierarchical processing?
does hierarchical processing solve the mystery of neural representation of complex visual stimuli? Could it be that higher areas of the visual system contain neurons that are specialized to respond only to a specific object, so that the object would be represented by the firing of that one type of specialized neuron?
As we will see next, this is not exactly what is happening, as instead the neural representation of specific objects most likely involves a number of neurons working together.
96
The problem of neural representation for the senses has been called
problem of sensory coding,
97
What does sensory code refer to?
How neural firing represents various characteristics of the environment.
98
What is specificity coding?
The representation of a specific stimulus by the firing of neurons that respond only to that stimulus.
An example would be the signalling of a person’s face by the firing of a neuron that responds only to that person’s face.
99
What does figure 2.10a show?
specificity coding
* hows how a number of neurons respond to three different faces.
* Only neuron #4 responds to Ian’s face, only #9 responds to Hannah’s face, and only #6 responds to Sam’s face.
* Also note that the neuron specialized to respond only to Ian, which we can call an “Ian neuron,” does not respond to Hannah or Sam. In addition, other faces or types of objects would not affect this neuron. It fires only to Ian’s face.
100
In the literature, the idea of highly specialized cells that fire only to one specific type of stimulus (or one particular person or concept), became known as the existence of
grandmother cells (Gross, 2002)
101
The disadvantage of specificity coding
* unlikely to be correct. Even though there are neurons that respond to faces, these neurons usually respond to a number of different faces (not just Ian’s). There are just too many different faces and other objects (and colours, tastes, smells and sounds) in the world to have a separate neuron dedicated to each object. In addition, this would be an extremely vulnerable way of representing things because what would happen, for example, if the one single neuron representing “Ian” decayed or got destroyed?
102
What is an alternative to the idea of specificity coding?
number of neurons are involved in representing an object
The notion of one, versus a few, versus many neurons representing a particular face, object or concept is slightly misleading. Indeed, in reality this is more likely to correspond to a few thousand, versus a few hundred thousand, versus a few million neurons (out of about a billion in the medial temporal lobe
103
What is population coding?
Neural representation of a stimulus by the pattern of firing of a large number of neurons.
particular object by the pattern of firing of a large number of neurons.
104
How is population coding demonstratedin this figure?
According to this idea, Ian’s face might be represented by a certain pattern of firing of ten different neurons, Hannah’s face by a different pattern, and Sam’s face by yet another pattern of the same ten neurons
105
Advantage of population coding?
* large number of stimuli can be represented, because large groups of neurons can create a huge number of different patterns. There is good evidence for population coding in the senses and for other cognitive functions as well.
106
Disadvantage of population coding
For some functions however, a large number of neurons aren’t necessary. Sparse coding occurs when small groups of neurons are involved.
107
When does sparse coding appear?
Neural coding based on the pattern of activity in small groups of neurons
occurs when a particular object is represented by a pattern of firing of only a small group of neurons, with the majority of neurons remaining silent.
108
How is sparse coding seen in figure 2.10
* represent Ian’s face by the pattern of firing of a few neurons (neurons 2, 3, 4 and 7). Hannah’s face would be signalled by the pattern of firing of a few different neurons (neurons 4, 6 and 7), but possibly with some overlap with the neurons representing Ian, and Sam’s face would have yet another pattern (neurons 1, 2 and 4).
* Notice that also in this case a particular neuron can respond to more than one stimulus. For example, neuron #4 responds to all three faces, although most strongly to Hannah’s.
109
Memories are also represented by the firing of neurons, but there is a difference between representation of perceptions and representation of memories
neural firing associated with experiencing a perception is associated with what is happening as perception is occurring. Firing associated with memory is associated with information about the past that has been stored in the brain.
We know less about the actual form of this stored information for memory, but it is likely that the basic principles of population and sparse coding also operate for memory, with specific memories being represented by particular patterns of stored information that result in a particular pattern of nerve firing when we experience the memory.
110
Which approach refers to the idea that a topic can be studied in a number of different ways, with each one contributing its own dimension to our understanding?
Level of analysis
Levels of analysis refers to the idea that a topic can be studied in a number of different ways, with each approach contributing its own dimension to our understanding.
111
Studying _____ is to studying the performance of a gaming mouse as studying _____ is to studying the hardware and software that affect its performance.
behaviour; physiology
studying behaviour is to studying the performance of a gaming mouse as studying physiology is to studying the hardware and software that affect its performance.
112
Although early anatomists viewed neurons as forming a continuous structure called a \_\_\_\_\_, Ramon y Cajal proposed the \_\_\_\_\_, which recognized that neurons are distinct, individual structures that communicate with each other.
neural net; neuron doctrine
Early anatomists believed structures they saw when looking at stained brain tissue to be continuous, like a highway system in which one street connects directly to another, but without stop signs or traffic lights, and called it the neural net. Cajal's discovery that individual units called neurons were the basic building blocks of the brain was the centerpiece of neuron doctrine – the idea that individual cells transmit signals in the nervous system, and that these cells are not continuous with other cells as proposed by nerve net theory.
113
Because of \_\_\_\_\_, it is possible for a signal to be transmitted across the gap that separates the end of the axon from the dendrite or cell body of another neuron.
Neurotransmitter
When signals reach the synapse at the end of the axon, a chemical called a neurotransmitter is released. This neurotransmitter makes it possible for the signal to be transmitted across the gap that separates the end of the axon from the dendrite or cell body of another neuron.
114
According to the principle of \_\_\_\_\_, everything a person experiences in based on a complicated pattern of firing neurons.
Neural representation
The principle of neural representation states that everything a person experiences is based not on direct contact with stimuli, but on representations in the person's nervous system
115
When stimulus intensity increases, the _____ of neurons increases.
firing rate
Increasing the intensity of a stimulus by, for example, presenting a brighter light, results in increasing the firing rate of neurons.
116
Hubel and Wiesel (1960s) found that neurons they called _____ responded to characteristics of visual stimuli such as orientation, movement, and length.
Feature detectors
Studying cats, Hubel and Wiesel found that each neuron in the visual area of the cortex responded to a specific type of stimulation presented to a small area of the retina. They called these special neurons feature detectors.
117
Elsa is recording from ten neurons in an area of the brain involved in processing information about faces. She finds that one neuron responds to Liam's face and only Liam's face; one neuron responds to Sarah's face and only Sarah's face; and one neuron responds to Noah's face and only Noah's face. Elsa's findings are most consistent with _____ coding.
Specificity
The idea that an object could be represented by the firing of a specialized neuron that responds only to that object is called specificity coding.
118
Esther is recording from twelve neurons in an area of the brain involved in processing information about faces. She finds that neurons 1, 3, 6, and 9 respond to Liam's face and only Liam's face; neurons 2, 4, 5, and 8 respond to Sarah's face and only Sarah's face; and neurons 7, 8, 10, and 11 respond to Noah's face and only Noah's face. Esther's findings are most consistent with _____ coding.
identity
Population
Population coding is the representation of a particular object by the pattern of firing of a large number of neurons.
119
What did Descrate believe?
Mind is distinct but could influence matter
Believe that mind and matter are related and believed that mind has control over brain via pineal gland (endocrine organ that secrete melatonin)
Called Mind Body Dualisim
120
Anatomical References
1st
1. Rostral - front
2. Dorsal - top of brain
3. Caudal - back of brain
4. Ventral - bottom of brain
121
Anatomical references
2
1. Anterior - front
2. Posterior - back
3. Lateral - Side of brain (outside)
4. Medial (towards the middle)
5. Ipsi lateral - information to the side of brain to right side of body
6. Contra-lateral - left side brain control right side of body (opposite)
122
123
