1 Exam Flashcards
Test Thursday
What are some of the cognitive functions that are damaged?
Memory, language, and perception
What do they study?
Genetics,astronomy,congitive science, mutations supernovas and connive deficits.
What are the basic cognitive functions?
Visual perception&object recognition
Language comprehension &production
Memory
Spatial cognition
Motor control
What were the patient name that had carbon monoxide?
What is goodie et al.(1991)
What is Neurotypical?
Neurological normal control patients
What is orientation task?
Is required to the responding shapes sizes of rectangular wooden block?
What is shape/size task?
To put the blocks into the place?
What did goodie al(1991) did with her hand?
She had turn her hand orientation bad and cannot put the card she was very slow.
What is Milner et al(1999)? What were the 3 main points?
Patient AT
* brain damage from cerebral hemorrhage
* Neurotypical control participants
* Tested on pointing to a visual target
* AT is impaired: optic ataxia
What is optic Ataxia?
He was always very fair away(from the dot)
What were the two conditions?
Immediate(points when the light is on)
Delayed(target then goes off delayed)
Question: Why does Coltheart (1997) consider cognitive neuropsychology a branch of cognitive psychology rather than neuropsychology?
Answer: Coltheart argues that cognitive neuropsychology focuses on understanding the mind’s structure and processes, using evidence from brain-injured patients to make inferences about normal cognitive functions. Therefore, it aligns more with cognitive psychology, which studies mental functions, than with neuropsychology, which emphasizes the brain’s structure and its relationship to behavior.
Focus on Brain-Injured Patients: Evidence from patients with brain injuries is crucial for cognitive neuropsychology. It uses these cases to infer how typical cognitive functions work by observing which aspects of cognition are disrupted.
Link to Cognitive Psychology: The approach is more closely aligned with cognitive psychology because both fields focus on understanding mental processes (e.g., memory, language, perception) rather than on the physical brain itself.
Distinction from Neuropsychology: Coltheart argues that traditional neuropsychology is more concerned with understanding the brain’s anatomy and its connections to behavior, whereas cognitive neuropsychology looks at how specific mental functions break down due to localized brain damage.
Modularity Hypothesis: Coltheart supports the idea that cognitive functions are modular, meaning distinct processes in the mind can be individually affected by brain damage, which helps in mapping out the architecture of cognition.
Double Dissociation: The use of double dissociation—where two patients show opposite patterns of cognitive impairment—helps in identifying independent cognitive systems and further differentiates cognitive neuropsychology from neuropsychology, which tends to focus on broader correlations between brain areas and behavior.
Question: What are the two complementary goals of cognitive neuropsychology according to Coltheart (1997)?
To Understand the Functional Architecture of Normal Cognitive Processes:
The first goal focuses on discovering how various cognitive processes, such as perception, memory, language, and attention, are organized within the mind. This involves determining how these processes are divided into distinct modules or systems that handle specific tasks (e.g., processing visual information, understanding speech, or forming new memories). Cognitive neuropsychologists aim to develop models that explain how these systems work in a normal, healthy brain, including how they interact with one another. The ultimate goal is to reveal the underlying “architecture” or structure that supports all cognitive functions.
For example, in studying language processing, researchers might want to know how different regions of the brain contribute to understanding and producing language, and how these processes are separated or integrated. By mapping out these systems in a healthy mind, cognitive neuropsychologists build a framework for understanding typical cognition.
To Use Cognitive Models of Normal Function to Explain Impaired Cognitive Abilities in Brain-Damaged Patients:
The second goal is to apply these models of normal cognitive function to better understand and explain the cognitive impairments that result from brain damage. By comparing a brain-damaged patient’s performance to the expected normal functioning, cognitive neuropsychologists can pinpoint where and how the damage has disrupted cognitive processes.
For instance, if a patient with brain damage has difficulty recognizing faces (a condition called prosopagnosia), the cognitive neuropsychologist would use their model of face recognition in a healthy brain to figure out which part of the cognitive system is impaired. By understanding the normal architecture of face processing, they can identify the specific cognitive function that has been disrupted by the brain injury. This approach not only helps explain the patient’s difficulties but also allows researchers to refine their models of normal cognitive processes by observing how damage affects specific systems
Answer: The two goals are: 1) To understand the functional architecture of normal cognitive processes, and 2) To use cognitive models of normal function to explain impaired cognitive abilities in brain-damaged patients.
Question: Do Ellis & Young (1988) agree with Coltheart about the goals of cognitive neuropsychology?
Agreement:
Common Goal: Both Ellis & Young and Coltheart agree that cognitive neuropsychology seeks to understand normal cognitive processes by studying cognitive impairments in brain-damaged individuals. They both use evidence from these impairments to make inferences about how the mind’s cognitive systems are structured in healthy people.
Use of Cognitive Models: Both emphasize the importance of cognitive models to explain the functioning of the mind. They use these models to describe both normal cognition and the impairments caused by brain damage.
Differences:
Emphasis on Brain Structures: Where they diverge slightly is in their emphasis on the relationship between cognitive models and brain structures. Coltheart tends to focus more on the architecture of cognitive processes themselves, sometimes independent of specific brain regions. His approach is more about understanding the “mental architecture” rather than pinpointing where in the brain these processes occur.
In contrast, Ellis & Young place more importance on connecting cognitive models to the physical structures of the brain. They are more focused on the brain-behavior relationship and how specific cognitive deficits relate to damage in particular brain areas. This brings their approach closer to traditional neuropsychology, which tends to prioritize anatomical localization.
——————————————————-
Yes, Ellis & Young agree that cognitive neuropsychology aims to understand normal cognitive functioning through the study of cognitive impairments. They also emphasize the use of cognitive models to explain both normal and impaired functioning.
Question: What distinction do Ellis & Young (1988) draw between modes of explanation on pp. 3-4?
Descriptive Explanations: These explanations focus on identifying and describing patterns of behavior or cognitive deficits in patients without necessarily explaining why these patterns occur. They are observational in nature and are used to categorize behaviors, such as listing the symptoms a brain-damaged patient exhibits or describing how a patient performs on certain cognitive tasks. While useful, descriptive explanations do not delve into the underlying mechanisms responsible for these behaviors.
Causal Explanations: In contrast, causal explanations aim to uncover the underlying mechanisms that cause the observed behavior or deficits. In cognitive neuropsychology, the emphasis is on understanding why certain cognitive impairments occur and how they relate to specific disruptions in normal cognitive processes. Researchers use cognitive models to explain the causal relationships between brain damage and impaired function, linking these deficits to particular cognitive systems or structures within the mind.
Answer: Ellis & Young distinguish between descriptive explanations, which simply describe patterns of behavior, and causal explanations, which attempt to explain the underlying mechanisms causing these behaviors. In cognitive neuropsychology, the predominant mode of explanation is causal, as researchers seek to understand the underlying cognitive mechanisms.
What is the key assumption of modularity in cognitive neuropsychological research according to Ellis & Young (1988)?
Modularity is the assumption that cognitive functions are divided into independent, specialized units or modules that can operate separately. This assumption is crucial because it allows researchers to infer which cognitive systems are impaired based on the types of deficits observed in brain-damaged patients.
What is a dissociation in cognitive neuropsychology?
A dissociation occurs when a patient has a selective impairment in one cognitive function but retains another intact, suggesting these functions are supported by separate neural systems.
What is a double dissociation in cognitive neuropsychology?
Answer: A double dissociation is when two patients show opposite patterns of impairment, where Patient A can perform Task 1 but not Task 2, and Patient B can perform Task 2 but not Task 1. This provides stronger evidence that the two tasks rely on different cognitive systems.
Example of Double Dissociation:
Patient A: Suffers from brain damage that affects language comprehension but not speech production. This means Patient A can speak fluently (performing Task 1: speech production) but struggles to understand spoken language (cannot perform Task 2: language comprehension).
Patient B: Suffers from brain damage that affects speech production but not language comprehension. This means Patient B can understand spoken language (performing Task 2: language comprehension) but has difficulty producing fluent speech (cannot perform Task 1: speech production).
This complementary pattern of impairment (one patient impaired in comprehension but not speech production, and the other patient impaired in speech production but not comprehension) provides strong evidence that speech production and language comprehension are handled by distinct cognitive systems or processes.
Question: What is an association in cognitive neuropsychology?
Answer: An association is when two cognitive functions are impaired together in a patient, suggesting they might rely on the same or overlapping cognitive processes or systems.
How do Ellis & Young (1988) evaluate dissociations, double dissociations, and associations as evidence in cognitive neuropsychology?
Answer: Ellis & Young argue that dissociations provide evidence for the independence of cognitive systems, but double dissociations offer even stronger evidence. Associations are more difficult to interpret, as they could indicate shared systems or simply co-occurring damage.
Question: What is the main difference between cognitive neuropsychology and neuropsychology?
Answer: Cognitive neuropsychology is a branch of cognitive psychology, not neuropsychology. It focuses on understanding how cognitive functions operate, often using data from brain-damaged individuals to test cognitive theories. Neuropsychology, on the other hand, studies brain-behavior relationships, focusing on how brain lesions affect behaviors.
What is the primary aim of cognitive neuropsychology?
The primary aim of cognitive neuropsychology is to use data from individuals with cognitive impairments to test, extend, or develop theories about normal cognitive functions. These theories are then used to explain patterns of preserved and impaired abilities in brain-damaged individuals.
How do cognitive neuropsychologists differ from neuropsychologists in their approach to brain-damaged patients?
Cognitive neuropsychologists focus on studying cognition itself, using brain-damaged individuals to understand how specific cognitive functions work. They do not study the brain or brain-cognition relationships directly, whereas neuropsychologists focus on how specific brain areas relate to behavior and cognition.
What is developmental cognitive neuropsychology?
Developmental cognitive neuropsychology studies developmental disorders of cognition, where individuals fail to acquire certain cognitive abilities normally. It uses theories about how cognitive abilities are normally learned to understand and address these developmental failures
How does cognitive neuropsychology contribute to cognitive-neuropsychological assessment?
Cognitive neuropsychology provides theories about the processes underlying specific cognitive functions. These theories guide the development of assessment batteries, which test each component process to evaluate cognitive impairments more thoroughly.
What is the role of cognitive neuropsychology in rehabilitation?
In cognitive-neuropsychological rehabilitation, particularly in the restoration approach, the goal is to reinstate or target specific cognitive processes that have been lost or are difficult to acquire. This requires a detailed understanding of the processes that underlie normal cognitive functions.
What is cognitive neuropsychiatry?
Cognitive neuropsychiatry interprets psychiatric disorders, like schizophrenia or autism, as specific impairments of high-level cognitive abilities, such as “theory of mind.” It uses cognitive neuropsychological methods to investigate these psychiatric conditions.
The use of data from people with impairments of cognition to test, extend or develop theories
about how the particular cognitive task in question is normally carried out; and the use of such
theories to understand and explain the particular patterns of preserved and impaired abilities
seen in such people.
What is developmental cognitive neuropsychology?
Answer: Developmental cognitive neuropsychology focuses on developmental disorders of cognition, where individuals fail to acquire specific cognitive abilities normally, rather than losing them due to brain damage. It uses theories about how cognitive abilities are typically learned to understand and address these developmental issues.
Cognitive-neuropsychological assessmen
one has a theory about what the set of processes is
by which we normally accomplish a particular cognitive task, this automatically provides ideas
about how to assess impairments of the ability to perform this task. Assessment batteries
containing separate tests of each of these component processes are what is needed. Cognitive
neuropsychology makes proposals as to what these component processes actually are
Question: What cognitive impairment did PH suffer after his accident, despite other abilities being intact?
Question: What cognitive impairment did PH suffer after his accident, despite other abilities being intact?
Answer: PH experienced prosopagnosia, or an inability to recognize familiar faces. He could determine general features like age and gender but could not recognize people by their faces alone. He identified familiar individuals once they spoke.
hat aspects of PH’s cognitive abilities were preserved after his accident
PH’s language abilities, short-term memory, and verbal IQ (91) were preserved. He could read without difficulty and remembered things important to his daily life, although he performed poorly on formal long-term memory tests.
What is prosopagnosia, as observed in PH’s case?
Prosopagnosia is a condition where an individual is unable to recognize familiar faces. In PH’s case, although he could distinguish general features of a face (e.g., age, gender), he could not identify familiar people by sight and only recognized them once they spoke.
What is the axis Transvers? Sagittal and coronal?
You lookin in the middle of the brain, sagittal is on the side and corral is like the back,
EST, a 65-year-old well-educated man.
Condition: Anomia caused by a slow-growing tumor in the left hemisphere, removed when he was 53.
Difficulties:
Severe word-finding issues for common words like “piano,” “spider,” and “lamp.”
Constant “tip of the tongue” state.
Could not recall words for everyday objects, despite recognizing and understanding them.
Good comprehension of both spoken and written language.
Speech and reading aloud were impaired by word-finding problems.
what are other disorders
Object recognition, spatial
knowledge and orientation, speech comprehension, reading, writing, and
memory
What is Cognitive Psychology?
Cognitive psychology (without the neuro- prefix) is the study of those
mental processes which underlie and make possible our everyday ability
to recognise familiar objects and familiar people, to find our way around
in the world, to speak, read and write, to plan and execute actions, to
think, make decisions and remember
What are assortment?
associations between symp
toms. 1t is common in neuropsychology to discover that patients who are
impaired on task ‘l are also typically impaired on tasks 3, 4 and 5. Now,
it might be that ‘this association of deficits occurs because a cognitive
process required for the successful execution of task 1 is also required for
the successful execution of tasks 3, 4 and 5, so that a patient in whom
that process is damaged wiU experience problems with all these tasks.
According to Coltheart (1997), cognitive neuropsychology is a branch of
cognitive psychology @
cognitive neuroscience
neuropsychology
all of the above
the _______ hypothesis states that cognitive functions like reading or object recognition are carried out by the orchestrated activity of multiple independent processors, each carrying out a specific, relatively simple, sub-part of the overall function.
componentiality
compositionality
modality
Correct!
modularity
Cognitive neuropsychology falls into the category of scientific research that
studies diseases to find cures
Correct!
studies atypical situations or processes to understand typical situations or processes @
is descriptive rather than explanatory
What do cognitive neuropsychologists assume about the relationship between cognitive tasks (such as reading a word aloud, or solving a multi-digit multiplication problem) and cognitive processes carried out in the brain?
for each task, there is a cognitive process that performs the entire task and only that task
each task if performed by a collection of cognitive processes, all of which are used only for that task
Correct!
each task is performed by multiple cognitive processes, and each process may play a role in performing multiple tasks
each cognitive process performs many entire tasks
Which of these tasks require mental representations and computations?
signing your name
taking a photograph with your phone
flipping a light switch
recognizing a face
all of the above
all of the above
what are the types of articles?
empirical articles: report new findings & conclusions
* review articles: review previous findings
* theoretical articles: propose/discuss theories
what does the articles in reputable Journal do?
articles in reputable journals have been peer-reviewed
* provides quality control, but not a guarantee that research was done
properly or that conclusions are correct
What should you pay attention to readings?
in reading articles pay attention to
* theoretical questions
* how tasks or experiments are supposed to answer the
questions
* evidence
* theoretical conclusions
* argument linking the evidence to the conclusions
What is in the introduction?
- topic
- specific issues/questions
- previous research
- preview of methods, results,
conclusions
Standard Article Format
Milner et al. (1999)
What are discussions
- summary of results
- interpretation: use results to draw
conclusions about theoretical questions - broader implications
- article may include multiple experiments,
each with Introduction, Methods, Results,
Discussion, followed by General Discussion
at end
what is abstract?
ten combined with first
paragraph of introduction
Introduction, Method, Results,
Discussion
* may not be separated into
sections with headings
* typically less detailed than in
longer journal article
* figure captions often contain
much of the method
DF’s Performance:Goodale et al. (1991)
Patient DF
Task DF’s Performance
choose which of 4 lines matches orientation of slot grossly impaired
turn hand-held card to match slot grossly verbally indicate orientation of rectangular block grossly impaired
‘post’ card through slot
All impaired expect the last one
Goodale et al. (1991)
Patient DF who was she?
The patient that moved her hands.
Judge same or different for rectangular plaques
open thumb & index finger to indicate plaque width
reach out and pick up plaque
All growsly impaired expet the last one.
Using Goodale et. Al(1991) what had they believed in?
wo separate visual subsystems in brain
1) system for conscious perceptual judgments (vision-for-
perception)
2) system for automatic visual guidance of skilled actions
(vision-for-action)
How are system distinguished?
- not by the types of visual information they process
- but instead by how they use visual information
We propose that for DF
vision-for-perception system impaired
* vision-for-action system intact
* As a consequence, DF is
* impaired on tasks probing vision-for-perception
* normal on tasks probing vision-for-action
* If we don’t assume the distinction between
perception and action systems, we have no obvious
way to explain DF’s performance
What are the normal vision and Goodale/Milner Conception
the difference between them? Write them down.
Hammer->Visual sytem->shape, size,color->Object recognition and language, and action
Their hypothesis:
Hammer->early vision->vision for perception->object recognition and language
early vision->vision for action->Reaching and grasping
Milner et al. (1999)
Patient AT?
Who was he? What were the results when he went slow and fast?
What is vision for action system and vision for perception system based on at?
vIsion-for-action system
* provides precise information for online control of
reaching/pointing movements
* but cannot retain information for longer than about 2
seconds
Vision-for-perception system
* provides less precise location information
* but can retain information over time
What were the results of AT compared to normal individuals using the Vision-for-action and vision-for-perception.
In normal individuals
* vision-for-action system controls pointing in immediate task
→ high accuracy
* vision-for-perception system controls pointing in delayed task
→ slightly lower accuracy
In AT
* the vision-for-action system is impaired
* but AT still uses this system in the immediate task → very
large errors
* in the delayed task AT uses the vision-for-perception system
→ smaller (but still abnormally large) errors
* so vision-for-perception system must also be somewhat
impaired
What about DF patient results?
Task DF’s Performance
Immediate: point while target is present normal
Delayed: point 10 seconds after target turned off impaired
Did the outcome differ between conditions?
- seems like a simple question
- AT: pointing errors smaller in the delayed condition than in
the immediate condition - therefore, seems obvious that difference in delay caused a
difference in pointing accuracy - but actually not so simple
- suppose that AT’s ability to point to a visual target is
exactly the same for immediate and delayed pointing - would we expect her average error to be exactly the
same in the immediate and delayed conditions of the
experiment? - clearly not
Observed difference by chance
What do we do in Experiments?
Experiments are procedures for drawing causal conclusions
* in an experiment
* we manipulate some variable to create a difference between 2 (or
more) situations, or ‘conditions’
* determine whether the difference between conditions causes a
difference in some outcome
ABBA design
Experimental design in which two different tasks (A and B) are presented in the
order A, B, B, A, to minimize effects of order of task presentatio
achromatopsia. Impaired color vision. For the usage in the Milner et al. article, the correct term
is
cerebral achromatopsia, which refers specifically to impaired color vision resulting
from damage to the brain (as opposed to the more common forms of color blindness,
which result from defects affecting the cones in the retina).
agnosia.
deficit in which the patient is impaired in recognizing objects or other stimuli.
alexia.
. Impairment in reading.
Balint’s syndrome.
collection of symptoms, including optic ataxia and simultanagnosia,
that may result from bilateral damage to the parietal lobes.
bilateral.
ffecting both sides (of the brain), as in bilateral lesion
cortical blindness
Blindness resulting from damage to the visual areas of the brain, as opposed
to blindness resulting from damage to the eyes or to the pathways from eye to brain.
dissociation (or single dissociation
attern of results in which one task or cognitive ability
(e.g., ability to recognize faces) shows impairment, while another task or ability (e.g.,
ability to recognize objects) is intact, or at least much less impaired
Ipsilatera,Lesion, Motor
issociation (or single dissociation). Pattern of results in which one task or cognitive ability
(e.g., ability to recognize faces) shows impairment, while another task or ability (e.g.,
ability to recognize objects) is intact, or at least much less impaired.
ipsilateral. On the same side. Contrasts with contralateral (which means on the opposite side).
lesion. General term for tissue damage. A brain lesion is a site of damage in the brain.
motor. Adjective referring to movement; thus, the motor system is the set of brain regions,
nerves, and muscles involved in producing movements.
medial
Toward the center or middle
Neural substrate.
The brain tissue that underlies some ability, as in the neural substrate for face
recognition is probably in ventral posterior regions of the brain
Optic ataxia.
Inaccurate reaching for a visual target when the inaccuracy cannot be attributed to
a purely visual or purely motor deficit
Perspex.
. Plexiglass
Prehension
The act of taking hold or grasping with the hand
prosopagnosia.
Impairment in the ability to recognize faces, not due simply to poor visio
saccade,
sagittal.
simultagnosia (or simultanagnosia).
saccade (or saccadic eye movement). An eye movement in which the eyes jump quickly from
one position to another, as when looking from one object to another. One of two major
forms of eye movement (the other is smooth pursuit, in which the eyes continually track a
moving object).
sagittal. Referring to the plane that divides a structure into left and right parts (not necessarily
halves).
scotoma. A blind area in the visual field.
simultagnosia (or simultanagnosia). A visual deficit in which the patient may be able to see
and recognize details of an object or scene, but cannot put them together to perceive the ntire object or scene. Alternatively, may refer to a visual deficit in which the patient can
only perceive one object at a time even when multiple objects are within the visual field.
tactile,transcranial magetic stimulation (TMS).visual agnosia.,visual form agnosia,visuomotor control,visuospatial., and whole-body locomotion
tactile. Adjective referring to touch.
transcranial magetic stimulation (TMS). Non-invasive procedure for creating temporary
disruption of functioning in a restricted brain area, by applying one or more brief
magnetic pulses via a coil positioned near the scalp over the targeted brain area.
visual agnosia. A deficit in recognizing visually-presented objects or other stimuli.
visual form agnosia. Visual agnosia resulting from impairment in perceiving the shapes and/or
other visual properties (e.g., texture, orientation) of objects.
visuomotor control. Use of visual information to guide movement, as when reaching for a
visible object.
visuospatial. Adjective referring to tasks, abilities, or cognitive processes that involve spatial
information obtained through vision. For example, judging whether two lines presented
on a computer are parallel or converging would be a visuospatial task.
whole-body locomotion. Walking or running.
Flashcard: Testing Patient DF’s Ability to Use Visual Information about Orientation
Key Task 1: Posting Task
Description: DF was asked to insert a card into a slot at various orientations.
Findings: DF could not verbally describe or perceive the orientation of the slot but could correctly orient the card to post it into the slot.
Conclusion: DF’s visuomotor actions (using visual information for action) were intact, despite her perceptual impairment
Key Task 2: Matching Task
Description: DF was asked to rotate a handheld card to match the orientation of a visible slot (no posting).
Findings: DF performed poorly, unable to correctly match the card’s orientation to the slot.
Conclusion: DF’s perceptual knowledge of orientation was impaired.
Tasks on Which Patient DF Performed Well:
Description: DF was asked to insert a card into a slot presented at different orientations.
Performance: DF performed well on this task, correctly orienting the card to match the slot and “posting” it successfully, despite being unable to consciously describe the orientation of the slot.
Conclusion: This demonstrated that DF’s dorsal stream (responsible for visually guided actions) was intact, allowing her to use visual information for motor actions even though her conscious perception was impaire
On which tasks was she impaired?Df
On the perception of hand.
What tasks were used to test DF’s ability to use visual information about the sizes of objects, and what were the outcomes?
erceptual Size Judgment Task:
DF was asked to estimate the size of objects.
Outcome: Performed poorly, showing impaired conscious perception of object size.
Grasping Task:
DF had to grasp objects of different sizes.
Outcome: Successfully adjusted her grip aperture to the size of objects, demonstrating intact visuomotor control.
Posting Task (Slot Task):
DF was asked to post a card through a slot of varying orientations.
Outcome: Could not verbally describe the slot’s orientation but could accurately post the card, showing her ability to use visual information for action.
5) Tasks on Which Patient DF Performed Well:
Posting Task:
Description: DF was asked to insert a card into a slot presented at various orientations.
Performance: DF performed well on this task, correctly orienting the card to match the slot and successfully posting it, despite being unable to consciously describe the orientation.
Conclusion: This showed that her dorsal stream (responsible for guiding actions) was intact, allowing her to perform visuomotor tasks accurately.
6) Tasks on Which Patient DF Was Impaired:
Matching Task:
Description: DF was asked to rotate a card to match the orientation of a visible slot, but without inserting it.
Performance: DF was impaired, unable to accurately match the orientation of the card to the slot.
Conclusion: This indicated a deficit in her ventral stream, which is responsible for conscious visual perception of orientation.
What interpretation do the authors offer for DF’s task performance results?
The authors interpret DF’s results as evidence for the two-stream hypothesis of visual processing:
Ventral Stream (What Pathway) Impairment:
DF’s inability to consciously perceive object size, shape, or orientation is due to damage to her ventral stream, which is responsible for object recognition and visual perception.
Dorsal Stream (How Pathway) Intact:
DF’s preserved ability to grasp objects and perform visuomotor tasks despite her perceptual deficits is due to the intact dorsal stream, which guides actions based on visual information.
This suggests that perception and action rely on separate visual pathways in the brain.
What tasks were administered to patient AT and control participants?
Pointing Task with Immediate Feedback:
Description: In this task, both AT and control participants were asked to point to a visual target using a hand or pointer. They received immediate visual feedback of their pointing action, meaning they could see their movements in real time.
Purpose: This task assesses baseline pointing accuracy without any delay, allowing a comparison with how the participants perform under normal conditions.
Pointing Task with Delayed Feedback:
Description: In this task, AT and control participants were asked to point to a target, but the visual feedback was delayed by a specific time interval (e.g., 200 ms or more). They could see the results of their pointing action only after the delay, preventing them from relying on real-time adjustments.
Purpose: This task tests the ability to maintain pointing accuracy when real-time feedback is unavailable, allowing researchers to investigate how participants compensate for the lack of immediate visual information.
Matching Task:
Description: In this task, participants were asked to match the orientation of a handheld object or a pointer with a visual target (similar to DF’s task but likely focused on orientation or spatial matching).
Purpose: This task assesses perceptual abilities to align objects or point accurately without requiring any specific motor actions
What was the pattern of results for control participants?
Immediate Feedback Condition:
Performance: Control participants performed very well, with low error rates.
Outcome: High accuracy due to the ability to use real-time visual feedback to adjust movements.
Delayed Feedback Condition:
Performance: Control participants showed increased pointing errors and poorer accuracy.
Outcome: Difficulty adjusting to delays in visual feedback, leading to overcorrections or undercorrections. The longer the delay, the greater the error
Flashcard: Pattern of Results for Patient AT
Immediate Feedback Condition:
Performance: AT performed less accurately than controls, with more pointing errors.
Outcome: Impaired ability to use real-time visual feedback, showing greater error than control participants.
elayed Feedback Condition:
Performance: AT showed fewer errors in the delayed condition compared to the immediate condition.
Outcome: AT’s accuracy improved with delayed feedback, likely due to reliance on a different motor control strategy.
What was the pattern for patient DF?
Perception Tasks (e.g., Matching Task):
Performance: DF performed poorly, unable to accurately match or describe the orientation of objects.
Outcome: DF was impaired in tasks requiring conscious visual perception of object orientation.
Action Tasks (e.g., Posting Task):
Performance: DF performed well, accurately posting a card into a slot at various orientations.
Outcome: DF’s ability to perform visually guided actions was intact, demonstrating preserved dorsal stream function.
Flashcard: Interpretation of Patient DF’s Results by Authors
Two Visual Pathways (Two-Streams Hypothesis):
Ventral Stream (“What” Pathway):
Responsible for object recognition and conscious visual perception.
DF’s impairment in tasks like matching orientation is due to damage in this stream.
Pathway runs from the occipital lobe to the temporal lobe.
Dorsal Stream (“Where/How” Pathway):
Responsible for visuomotor control, guiding actions based on spatial information.
DF’s intact performance in tasks like posting a card is linked to preserved dorsal stream function.
Pathway runs from the occipital lobe to the parietal lobe.
Dissociation Between Perception and Action:
Perception (ventral stream) and action (dorsal stream) rely on different neural pathways.
DF’s ability to act (post card) despite being unable to perceive orientation shows a functional separation between these streams.
Visually guided actions can occur without conscious recognition of objects.
Functional Independence of the Dorsal Stream:
The dorsal stream can operate independently of the ventral stream, allowing DF to perform actions without conscious perception.
Motor control systems can use spatial information for actions without requiring explicit object recognition.
Implications for Visual Agnosia:
DF’s case shows that visual agnosia involves specific impairments in conscious perception (ventral stream), while action-related vision (dorsal stream) may remain intact.
The case challenges the idea that visual agnosia involves global visual deficits and supports the view of separate neural mechanisms for perception and action.
Summary:
DF’s case supports the two-streams hypothesis, highlighting a clear division between the ventral stream (perception) and the dorsal stream (action).
This case illustrates how visuomotor control can remain functional despite significant conscious visual recognition deficits
What is the balitiant syndrome?
Ba ̈lint’s syndrome, including visual disorientation, simultagnosia
and severe optic ataxia for targets in her peripheral visual ¢eld.
What D.F tested on the Milners Et AL?
Yeah, she was study and they found out that she been working normally under the first circumstance of rapid eye tracke and pointing, when delayed she had gone absolutely wrong. Supporting the hypothesis created by the Df results.
Her parietal lobes were damaged.
Peer review is the practice in which experts on the topic of an article ?
Write critical commentaries after the article is published
provide written evaluations of an article before it is accepted for publication @@
certify that the results and conclusions of the article are unquestionably valid
provide brief statements that endorse the article and are published along with the article
Which of the following is likely to be found in the Methods section of an article?
a description of the procedures used in testing the participants
a description of any specialized equipment used in the study
a description of the stimuli (such as words or pictures) presented to participants
All@
Which section of a research article is most likely to include a review of prior research on the research topic?
Introduction
Methods
Results
Discussion
The section of an article that provides a brief summary of the questions, methods, results, and conclusions is called the ?
overview
precis
abstract ###
Patient DF was tested on a ‘posting’ task. This task involved?
Touching a target location on a screen
Correct!
inserting a card into a slot
inserting small wooden sticks into holes
uploading a photo to a social media site
In the study of patient DF, the posting task was used to probe the ability of the ______ system to use information about ______.
vision-for-perception/shape
vision-for-perception/orientation
vision-for-action/shape
Correct!
vision-for-action/orientatio
In the study of patient DF, the posting task was used to probe the ability of the ______ system to use information about ______.
vision-for-perception/shape
vision-for-perception/orientation
vision-for-action/shape
Correct!
n an experiment we have not discussed, Goodale & Milner’s patient DF walked through a sort of obstacle course in which she needed to step over blocks of different heights. She performed normally, raising her foot an appropriate distance for each block—in other words, raising her foot higher for tall blocks than for short blocks. However, when she was shown pairs of the blocks and asked to say which one was taller, she was very inaccurate.
This pattern of performance is an example of a(n)
association
double association
Correct!
dissociation
double dissaciation
We would expect Goodale & Milner to interpret the result by proposing that walking the obstacle course involved the ________ system, whereas judging which of two blocks was taller required the ______ system
vision-for-perception/vision-for-action
Correct!
vision-for-action/vision-for-perception
spatial-vision/object-vision
object-vision/spatial-vision
The grip aperture of a person reaching out to pick up an object is
the places that are grasped on the object
the force exerted on the object by the person’s grasp
the orientation of a line drawn from finger to thumb on the reaching hand
Correct!
the distance between finger and thumb on the reaching hand
Milner et al. (1999) found that patient AT’s reaching accuracy was higher when she was forced to wait 5 seconds after the target light went off before reaching (delayed condition), than when she reached while the target light was on (immediate condition). The researchers interpreted these results by assuming that
the 5-second delay gave an impaired vision-for-action system enough time to determine the location of the target
an impaired vision-for-perception system interfered with the normal vision-for-action system in immediate reaching, but not in delayed reaching
Correct!
an impaired vision-for-action system controlled reaching in the immediate condition, but the more-intact vision-for-perception system took over in the delayed condition
the 5-second delay gave the perception and action systems time to work together, producing better performance than either system could achieve alone
Hillis & Caramazza (1989) studied a patient (ML) with a spelling deficit resulting from a stroke. When they compared the words ML spelled correctly with those she misspelled, here is what they found: ‘The mean length of correctly-spelled words was 4.62 letters, and the mean length of misspelled words was 5.52 letters (t = 8.12; p < .0001).’ What can we conclude from this sentence?
Correct!
the probability that the length difference between correctly-spelled and mis-spelled words was due to chance is less than 1 in 10,000
the probability that the length difference was due to chance is 8.12 in 10,000
the probability that ML spells short words more accurately than long words is less than 1 in 10,000
the probability that ML spells short words more accurately than long words is 8.12 in 10,000
Hillis & Caramazza (1989) studied a patient (ML) with a spelling deficit resulting from a stroke. When they compared the words ML spelled correctly with those she misspelled, here is what they found: ‘The mean length of correctly-spelled words was 4.62 letters, and the mean length of misspelled words was 5.52 letters (t = 8.12; p < .0001).’ What can we conclude from this sentence?
Correct!
the probability that the length difference between correctly-spelled and mis-spelled words was due to chance is less than 1 in 10,000
the probability that the length difference was due to chance is 8.12 in 10,000
the probability that ML spells short words more accurately than long words is less than 1 in 10,000
the probability that ML spells short words more accurately than long words is 8.12 in 10,000
An article by Hamann and Squire (1997), which we will read later in the course, describes research with patient EP, who has a severe memory deficit. Hamann & Squire report differences between conditions for 2 tasks presented to EP, stem completion and perceptual identification. (The nature of the tasks doesn’t matter for this question.) The statistical test results reported for the tasks are as follows:
stem completion: t(5) = 2.63, p < .05
perceptual identification: t(11) = 4.66, p < .001
For which task was the difference between conditions more likely to have occurred due to chance?
Correct!
stem completion
perceptual identification
cannot be determined from the information given
For which task was the difference between conditions more likely to have occurred due to chance?
Correct!
stem completion
perceptual identification
cannot be determined from the information given