Ch-2 Cognitive Neuroscience

Example of Broca's aphasia

Alright.... Uh ... stroke and un.... I... huh tawanna guy.... H... h... hot tub and.... And the.... Two days when uh.... Hos... uh.... Huh hospital and uh... amet... am... ambulance.

Physiological Levels of Analysis

Chemical processes, neurons activated, brain structures activated, groups of brain structures activated

what would happen if kittens were reared in an environment consisting only of verticals?

Colin Blakemore and Graham Cooper (1970) answered this question by rearing kittens in a space in which they saw only vertical black and white stripes on the walls. After being reared in this vertical environment, kittens batted at a moving vertical stick but ignored horizontal objects. The basis of this lack of response to horizontals became clear when recording from neurons in the kittens' brains revealed that the visual cortex had been reshaped so it contained neurons that responded mainly to verticals and had no neurons that responded to horizontals

task-related fMRI

Complex statistical procedures are used to determine the ___________________—the change in brain activity that can be linked specifically to the task.

Neurons

Create & transmit info. about what we experience & know

Basic principle of brain organization

Localization of function

According to Cajal, the role of neuron is true transmit signals

True

Adrian found that the shape and height of the action potential remained the same as he increased the pressure, but the rate of nerve firing—that is, the number of action potentials that traveled down the axon per second increased

True

Although the idea of specificity coding is straightforward, it is unlikely to be correct.

True

An advantage of population coding is that a large number of stimuli can be represented, because large groups of neurons can create a huge number of different patterns.

True

Another way functional connectivity can be determined is by measuring the task-related fMRI at the seed and test locations and determining the correlations between the two responses

True

Functional connectivity and structural connectivity are not, therefore, the same thing, but they are related, so regions with high structural connectivity often show a high level of functional connectivity

True

The reason there are two areas for humans and two for animals is that each area represents different features related to humans or animals.

True

a particular neuron can respond to more than one stimulus.

True

the inside of the 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.

True

Resting potential

When the axon, or nerve fiber, is at rest, the meter records a difference in potential between the tips of the two electrodes of 270 millivolts (a millivolt is 1/1000 of a volt). This value, which stays the same as long as there are no signals in the neuron, is called the _________________.

Many cognitive functions are served by the __________________

cerebral cortex

neurons in the temporal lobe respond to ____________ stimuli

complex

connectome

indicate the "structural description of the network of elements and connections forming the human brain" or more simply, the "wiring diagram" of neurons in the brain

Neural networks

interconnected areas of the brain that can communicate with each other

The 2 facts researchers discovered when they began recording from neurons in areas outside the primary visual area

1) Many neurons at higher levels of the visual system fire to complex stimuli like geometrical patterns and faces; and (2) a specific stimulus causes neural firing that is distributed across many areas of the cortex

4 principles of neural networks

1) There are complex structural pathways called networks that form the brain's information highway. 2. Within these structural pathways there are functional pathways that serve different functions. 3. These networks operate dynamically, mirroring the dynamic nature of cognition. 4. There is a resting state of brain activity, so parts of the brain are active all the time, even when there is no cognitive activity.

Cajal's conclusions 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 called a synapse 2) Neurons are not connected indiscriminately 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. These neurons, called receptors are similar to brain neurons in that they have an axon, but they have specialized receptors that pick up information from the environment.

Nerve net

A network believed to be continuous, like a highway system in which one street connects directly to another, but without stop signs or traffic lights. When visualized in this way, this provided a complex pathway for conducting signals uninterrupted through the network.

default mode network.

A network was discovered that responded not when people were engaged in tasks—but when they weren't

Who said that if nerve impulses "are crowded closely together, the sensation is intense, if they are separated by long intervals the sensation is correspondingly feeble" and where?

Adrian in his book "The Basis of Sensation"

action potential

As the impulse passes the recording electrode, the charge inside the axon rises to 140 millivolts, compared to the outside. As the impulse continues past the electrode, the charge inside the fiber reverses course and starts becoming negative again until it returns to the resting potential. This impulse is called the _______________, lasts about _____________ action potential , 1 millisecond (1/1000)

Explain what happens as the nerve impulse passes the electrode

As the nerve impulse passes the electrode, the inside of the fiber near the electrode becomes more positive. As the nerve impulse moves past the electrode, the charge in the fiber becomes more negative. Eventually the neuron returns to its resting state. Look at diagram on pg-30

Dendrites

Branches out from the cell body and receive signals from other neurons

______________ and ___________________ observations showed that different aspects of language— production of language and comprehension of language—were served by different areas in the brain. Goldstein, E. Bruce. Cognitive Psychology: Connecting Mind, Research, and Everyday Experience (Page 39). Cengage Learning. Kindle Edition.

Broca's, Wernicke's

Wernicke's area.

Damage to the temporal lobe

_____________________ are not, therefore, simply static diagrams but involve constantly changing activity within and across networks

Functional networks

What other discoveries did Adrian make?

He found that each action potential travels all the way down the axon without changing its height or shape. This property makes action potentials ideal for sending signals over a distance, because it means that once an action potential is started at one end of an axon, the signal will still be the same size when it reaches the other end.

Receptors

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. These neurons, called _________________

Bharat Biswal and coworkers (1995).

Introduced the procedure for measuring resting-state functional connectivity

Example of Wernicke's aphasia:

It just suddenly had a feffort and all the feffort had gone with it. It even stepped my horn. They took them from earth you know. They make my favorite nine to severed and now I'm a been habed by the uh stam of fortment of my annulment which is now forever.

Camillo Golgi

Italian anatomist who developed a staining technique in which a thin slice of brain tissue was immersed in a solution of silver nitrate. This created pictures in which fewer than 1 percent of the cells were stained, so they stood out from the rest of the tissue and the individual cells were stained completely, so it was possible to see their structure

test location

Measure the resting-state fMRI at another location

Similarity between memory and perception representation

Memories are also represented by the firing of neurons like perception

Adrian recorded electrical signals from single neurons using ________________

Microelectrodes

Neural circuits

Neurons are not connected indiscriminately to other neurons but form connections only to specific neurons. This forms groups of interconnected neurons, together form ______________________

_________________ 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

Neurotranmitter

Could it be that higher areas of the visual system contain neurons that are specialized to respond only to a specific object, so that object would be represented by the firing of that one type of specialized neuron?

No, because neural representation most likely involves a number of neurons working together.

Broca's aphasia.

Patients with this problem—slow, labored, ungrammatical speech caused by damage to Broca's area—are diagnosed as having

Broca's area

Paul Broca published work based on his study of patients who had suffered brain damage due to strokes that caused disruption of the blood supply to the brain. These strokes caused damage to an area in the frontal lobe that came to be called _______________________.

2 types of electrodes

Recording electrode & reference electrode

______________________ has become one of the main methods for determining functional connectivity.

Resting-state functional fMRI connectivity

Given the likelihood that even these special neurons are likely to fire to more than one stimulus, Quiroga and coworkers (2008) suggested that their neurons are probably an example of __________________.

Sparse coding

David Hubel and Thorsten Wiesel,

Started a series of experiments in which they presented visual stimuli to cats, and determined which stimuli caused specific neurons to fire. They 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.

What appears on the computer when a neuron's electrical signals are recorded?

The difference in charge between the recording and reference electrodes is fed into a computer and displayed on a computer monitor.

distributed representation.

The fact that looking at a face activates many areas of the brain is called

specificity coding.

The idea that an object could be represented by the firing of a specialized neuron that responds only to that object Only neuron 4 responds to Bill's face, only neuron 9 responds to Mary's face, and only neuron 6 responds to Raphael's face. Also note that the neuron specialized to respond only to Bill, which we can call a "Bill neuron," does not respond to Mary or Raphael. In addition, other faces or types of objects would not affect this neuron. It fires only to Bill's face.

difference between representation of perceptions and representation of memories. but it is likely that the basic principles of population and sparse coding also operate for memory,

The neural firing associated with experiencing a perception is associated with what is happening as a stimulus is present. Firing associated with memory is associated with information about the past that has been stored in the brain. Specific memories are represented by particular patterns of stored information that result in a particular pattern of nerve firing when we experience the memory.

Cajal

The person who made this cellular study of mental life possible. Also earned the Noble Prize in 1906.

problem of sensory coding,

The problem of neural representation for the senses

Time-series response

The resting-state fMRI of the seed location, is called a _______________ because it indicates how the response changes over time.

Synapse

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 _________________

Ramon y Cajal

Used 2 techniques to investigate the nerve net : 1) Used the Golgi stain, which stained only some of the cells in a slice of brain tissue. 2) decided to study tissue from the brains of newborn animals, because the density of cells in the newborn brain is small compared with the density in the adult brain.

Six Common Functional Networks Determined by Resting-State fMRI Network Function

Visual: Vision; visual perception Somato-motor: Movement and touch Dorsal Attention: Attention to visual stimuli and spatial locations Executive Control: Higher-level cognitive tasks involved in working memory and directing attention during tasks Salience: Attending to survival-relevant events in the environment Default mode: Mind wandering, and cognitive activity related to personal life-story, social functions, and monitoring internal emotional states

Patients such as this not only produce meaningless speech but are unable to understand other people's speech. Their primary problem is their inability to match words with their meanings, with the defining characteristic of ________________ being the absence of normal grammar

Wernicke's aphasia

Wernicke's aphasia:

Wernicke's patients produced speech that was fluent and grammatically correct but tended to be incoherent.

cerebral cortex

a layer of tissue about 3 mm thick that covers the brain The cortex is the wrinkled covering you see when you look at an intact brain

extrastriate body area (EBA),

activated by pictures of bodies and parts of bodies (but not by faces),

Axons

aka nerve fibers ; long processes that transmit signals to other neurons.

prosopagnosia, prosopagnosia

an inability to recognize faces. People with _______________________ can tell that a face is a face, but they can't recognize whose face it is, even for people they know well such as friends and family members

track-weighted imaging (TWI),

based on detection of how water diffuses along the length of nerve fibers.

Neuron

basic building blocks of the brain

Why was Blakemore and Cooper's experiment important?

because it is an early demonstration of experience-dependent plasticity.Their result from cat experiment supports the idea that perception is determined by neurons that fire to specific qualities of a stimulus (orientation, in this case).

If all nerve impulses are basically the same whether they are caused by seeing a red fire engine or remembering what you did last week, how can these impulses stand for different qualities?

different qualities of stimuli, and also different aspects of experience, activate different neurons and areas in the brain.

Principle of neural representation

everything a person experiences is based on representations in the person's nervous system.

Double dissociations have been demonstrated for _______________ and ___________________

face recognition, object recognition,

The _______________ receives signals from all of the senses and is responsible for _______________ of the senses, as well as higher cognitive functions like ______________ and _______________

frontal lobe, coordination, thinking, problem solving.

fusiform face area (FFA)

it is in the fusiform gyrus on the underside of the temporal lobe (Kanwisher et al., 1997), is the same part of the brain that is damaged in cases of prosopagnosia

subcortical areas

located below the cortex.

Reference electrode

located some distance away so it is not affected by the electrical signals.

Cell body

metabolic center of the neuron; it contains mechanisms to keep the cell alive.

most of our experience is ------------. That is, even simple experiences involve combinations of different qualities.

multidimensional.

All of the other locations have low correlations and so are not part of the _________________

network

hierarchical processing.

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 even higher areas, combining and interacting further and creating neurons that respond to even more complex stimuli such as faces. This progression from lower to higher areas of the brain is called ___________________.

feature detectors

neurons that respond to specific stimulus features such as orientation, movement, and length.

when the signals reach the synapse at the end of the axon, a chemical called a _____________ is released.

neurotransmitter

Edgar Adrian

recorded electrical signals from single sensory neurons, an achievement for which he was awarded the Nobel Prize in 1932

Studies of Japanese soldiers in the Russo-Japanese war of 1904-1905 and Allied soldiers in World War I showed that damage to the _______________ of the brain, where the __________________ is located (Figure 2.11), resulted in ______________, and that there was a connection between the area of the _______________ that was damaged and the place in _____________________ where the person was blind Goldstein, E. Bruce. Cognitive Psychology: Connecting Mind, Research, and Everyday Experience (Page 39). Cengage Learning. Kindle Edition.

occipital lobe, visual cortex, blindness, occipital lobe, visual space

double dissociation

occurs if damage to one area of the brain causes function A to be absent while function B is present, and damage to another area causes function B to be absent while function A is present.

Sparse coding

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. Sparse coding would represent Bill's face by the pattern of firing of a few neurons (neurons 2, 3, 4, and 7). Mary's face would be signaled by the pattern of firing of a few different neurons (neurons 4, 6, and 7), but possibly with some overlap with the neurons representing Bill, and Raphael's face would have yet another pattern (neurons 1, 2, and 4).

perceiving pictures representing indoor and outdoor scenes activates the ____________________. What is important for this area is information about spatial layout, because increased activation occurs when viewing pictures both of empty rooms and of rooms that are completely furnished

parahippocampal place area (PPA)

it could be argued that the introduction of the brain-scanning techniques _____________ in 1976 and _______________ in 1990 marked the beginning of the "imaging revolution."

positron emission tomography (PET), functional magnetic resonance imaging (fMRI)

Nerve net theory

proposed that signals could be transmitted throughout the net in all directions.

In some cases, people with ___________________ look into a mirror and, seeing their own image, wonder who the stranger is looking back at them

prosopagnosia

the magnitude of experience is related to the _______________

rate of nerve firing

Charles Gross' Experiment

recorded from single neurons in the monkey's temporal lobe. Gross's research team presented a variety of different stimuli to anesthetized monkeys. On a projection screen, they presented lines, squares, and circles. Some stimuli were light and some dark.The discovery that neurons in the temporal lobe respond to complex stimuli came a few days into one of their experiments, when they had found a neuron that refused to respond to any of the standard stimuli, like oriented lines or circles or squares except hands with fingers pointing up.

Recording electrode

recording tip inside the neuron

When the nerve is at rest, there is a difference in charge, called the ___________, of _____________ millivolts between the inside and the outside of the axon

resting potential, -70

movement of the finger causes an fMRI response at the location marked Motor (L). This location is called the _____________

seed location.

Memories are complicated. Some memories, called ____________ memories, last fleetingly, for only about ______ to ___________ seconds unless repeated over and over, as you might do to remember a phone number you forgot to store in your cell phone.

short-term, 10 to 15

Another tool for demonstrating localization of function is recording from ________________

single neurons.

Microelectrodes

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.

The ______________, which receives signals from the ____________, is in the _______________ and is responsible for perceptions of touch, pressure, and pain.

somatosensory cortex, skin, parietal lobe

localization of function

specific functions are served by specific areas of the brain.

Functional magnetic resonance imaging (fMRI)

takes advantage of the fact that neural activity causes the brain to bring in more oxygen, which binds to hemoglobin molecules in the blood. This added oxygen increases the magnetic properties of the hemoglobin, so when a magnetic field is presented to the brain, these more highly oxygenated hemoglobin molecules respond more strongly to the magnetic field and cause an increase in the fMRI signal.

Structural connectivity

the brain's "wiring diagram" created by nerve axons that connect different brain areas.

functional connectivity,

the extent to which neural activity in two brain areas are functionally correlated

resting-state fMRI—

the fMRI response measured while a person is at rest (that is, not performing a cognitive task).

Levels of analysis

the idea that a topic can be studied in a number of different ways, with each approach contributing its own dimension to our understanding. Ex: what happens inside the cylinder of a car versus in the hood are two different approaches to learning about a car.

Cajal's 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.

cortical equipotentiality

the idea that the brain operated as an indivisible whole as opposed to specialized areas

Population coding

the representation of a particular object by the pattern of firing of a large number of neurons According to this idea, Bill's, Mary's and Raphael's faces are each represented by a different pattern.

The reason for describing the microstructure of the brain as a continuously interconnected network

the staining techniques and microscopes used during that period could not resolve small details, and without these details the nerve net appeared to be continuous.

experience-dependent plasticity,

the structure of the brain is changed by experience. For example, when a kitten is born, its visual cortex contains feature detectors that respond to oriented bars. Normally, the kitten's visual cortex contains neurons that respond to all orientations, ranging from horizontal to slanted to vertical, and when the kitten grows up into a cat, the cat has neurons that can respond to all orientations.

neuropsychology

the study of the behavior of people with brain damage.

Cognitive neuroscience

the study of the physiological basis of cognition.

"how can nerve impulses stand for different qualities?"

there are neurons that fire only to specific qualities of stimuli.

One thing that the examples of perceiving faces, remembering, and language have in common

they involve experiences that activate many separated brain areas, and there is evidence that many of these areas are linked either by direct neural connections or by being part of a number of interconnected structures.

It is important to note that saying two areas are functionally connected does not necessarily mean that they directly communicate by neural pathways.

true

Objects and actions similar to each other are located near each other in the brain.

true

One interesting observation is that when the DMN is active, people's minds tend to wander

true

The test locations, Somatosensory and Motor (R), are highly correlated with the seed response and so have high functional connectivity with the seed location.

true

damage to areas outside of Broca's and Wernicke's areas can cause problems in producing and understanding language

true

thinking about episodic and semantic memories activates different areas of the brain

true

The auditory cortex, which receives signals from the ears, is in the ______________________

upper temporal lobe

it is important to realize that the _______________ is an early stage of visual processing, and that vision depends on signals that are sent from the _______________ to other areas of the brain.

visual cortex, visual cortex

Another effect of brain damage on ________________, reported in patients who have damage to the temporal lobe on the lower-right side of the brain, is __________________

visual functioning, prosopagnosia

problem of sensory coding,

where the sensory code refers to how neurons represent various characteristics of the environment.

Voxels,

which are small, cube-shaped areas of the brain about 2 or 3 mm on a side. Voxels are not brain structures but are simply small units of analysis created by the fMRI scanner. One way to think about voxels is that they are like the small, square pixels that make up digital photographs or the images on your computer screen, but because the brain is three-dimensional, voxels are small cubes rather than small squares.