Title: BV4 / Modul 4 / Attention

Q: What is an oldschool definition of attention?
A: The taking possession by the mind, in clear and vivid form, of one of what seem several simoultaneiusly possible objects or trains of thought
It implies withdrawal from some things in order to deal effectively with others

Q: What is a modern definition of attention?
A: The concious of unconcious function of the brain that focuses on some external or interal stimulus at the expense of fully processing other information

Q: What do we sometimes not even notice?
A: Sometimes we dont even notice that some aspcets of the environment come to our attention

Q: What is overt attention?
A: Overt attention is selective processing one location over others by moving ur senses in the direction of that location
- Ex. by looking at what u are paying attention to
- The opposite is covert attention

Q: What is covert attention?
A: Covert attention is paying attention without moving ur eyes

Q: What is the 2nd aspect of attention?
A: The 2nd aspect is that attention can be guided by external or internal stimuli - Exogenous and endogenous attention

Q: WHat is exogenous attention?
A: Exogenous attention means that ur attention is guided by something in ur environment, can be any external stimuli ex. can come up by suprise and guides ur attention to it

Q: What is endogenous attention?
A: Endogenous attention means that we decide to pay attention to certain aspects in our environment, guided by our expectations or goals and affected by our affective state (internal stimuli)

Q: What is attention always?
A: Attention is always selective, we are always missing out on some aspects of our environment - our brains capacity isnt big enough to process everything all the time

Q: How did Hermann von Helmholtz discover covert attention?
A: - He used a projector and a wall with letters on it and fixating his eyes on the middle if the screen but decided to covert his attention to some aspect to the screen
- The electric apparatus would shine a light somewhere on the screen, he didnt know where, but it was the same spot that his attention was drawn to prior to the spark and they he was able to discern the latters showing in this aspcet of the screen

Q: What ca be said about the use of Hermann's experiment nowadays?
A: Still experiment stil used today with the set up a little different to study covert attention

Q: WHat was alfred yarbus the first one to do?
A: He was the first to use eye-tracking

Q: How did alfred yarbus experiment on overt attention with his apparatus?
A: This apparatus detected eye movements that participants had while looking at pics, he gave them different tasks, like to look at the peeps in a pic and decide how old they were or look at the pic and see how rich or poor they were

Q: What did Yarbus discover with his eye-tracking experiment?
A: He could see that the eye movements and the areas people were paying attention to were very differnet depending on the task given

Q: HOw is eye tracking used today?
A: This type of research is still used today to check what u look at in ex. a supermarket
- Modern eye trackers are often combined with EEG

Q: How is the Posner cueing task investigating exogenous vs endogenous attention perfromed?
A: Participants would be asked to first fixate on the middle of the screen, this would be followed by a cue, while they were still asked to look at the cross (the cue could be an arrow, which would endogenously would draw the attention to the upcoming stimulus, so the partici would process this as an arrow that indicates that i need to look that way
- The cue could also be a frame indicating that the stoimulus  would be, this would be an ex.,  for exogenous cueing
- Both of these cues are valid so they actually indicate the real direction of the upcoming stimulus
- Using 80% of valid cues the partici would learn thatthe cue wold indicate the direction of the stimulus

Q: What would invalid cues do in the Posner cueing task investigating exogenous vs endogenous attention?
A: Invalid cues indicate to the wrong direction of the upcoming stimulus
- This would hinder the attentional process instead of facilitating it

Q: What are the effects of attentional cueing from the posner test?
A: - Whenever valid cueing was used the reaction time decreased where the stimulus was shown, participants were faster to react to the stimulus when their attention is already allocated in that direction
- While whenever an invalid cue was used the reacting time increased, it was harder and it took longer to react to the stimulus

Q: What was later shown in a second study related to the effects of attentional cueing from the posner test?
A: Later in a 2nd study it was shown that this process of facilitating allocational attention to a precued location can actually be worse when the interval between the presentation of the cue and presentation of the stimulus was longer
- This process is a means  by the brain to avoid that u re-allocate ur attention to a location that u have already focused on earlier - this is called inhibition of return

Q: What is inhibition of return?
A: This process is a means by the brain to avoid that u re-allocate ur attention to a location that u have already focused on earlier

Q: What happens
when attentional processes are disturbed by some brain dysfunction?
A: The symtome of attentional dysfunction is asscoiated with a variety of disorders, all of them affecting the brain

Q: Which disorders are associated with the symtome of attentional dysfunction/can disturb attention?
A: - Brain lesions (caused by: stroke, tumor, trauma,...) (hemispatial neglect)
- Neurodevelopmental disorders: ADHD, autism specturm disorders, schizophrenia,...
- Neurodegenerative disorders: Frontotemporal dementia, Parkinson's disease,...

Q: What can attention be disturbed by?
A: - Attenton can be disturbed by any brain lesion
  - They can be caused by ex. stroke , trauma, tumors, etc.

Q: What is attentional dysfunction often associated with?
A: - Neurodevelopmental disorders
- Neurodegenerative disorders

Q: What can brain lesions result in?
A: Hemispatial neglect

Q: What is a condition
associated with attentional dysfunction?
A: Hemispatial neglect - this is fairly common

Q: What is hemispatial neglect caused by?
A: Caused by lesions in the right parietal, right superior temporal or right frontal brain regions

Q: After what is hemispatial neglect common and why?
A: Common after stroke involving the middle cerebral artery
One of the most important arteries supplying blood to the brain is a cerebri media, this area in red is supplied by it and there is a large overlap with that region that is asscoiated with clinical symtomes of neglect

Q: Which bedside methods can be used to determine hemispatial neglect?
A: - Line cancellation
- Line bisecting
- Drawing
- Visual exploration (eye-tracking)

Q: How does hemispatial neglect show in the bedside methods for testing it?
A: - Line cancellation , pat is provided with a papaer of lineas and asked to cancel them out by drwaing anothe rlne through them , someone with neglect would mainly do this on one half/part of the paper, often the right side
- Linde bisection, pat is asked to evenly divide a line and the dividion woud be moved to the right hand side if they are affected by neglect
- U could aslo ask the pat to draw whaterver comes to mind, and often they would just sdraw half of the pic, like a clock
- In neglect the patients would just write numbers on one side on the clock
- If u have a eye trachaer avail, they can be asked to visually explore(look at a picture) and u would finns they they would only be scanning on ehalf of the picture

Q: What does it not mean whne patients with hemispatial neglect only performs tasks on one side of the visual field?
A: This does not mean that the person is blind on one side - its an attentional problem

Q: Where is it common to see neglect on a regular basis?
A: If u are working with the stroke unit

Q: What does this pic show?
A: Tests performed on people that exhibit hemispatial neglect

Q: What is done during a clinical examination of hemispatial neglect?
A: - Extinction test
- Activities of daily living

Q: What is neglect usually?
A: Neglect is most often not a total ignoarnce of one side of the body or the enviornemnt, usualy partial neglect

Q: How can partial neglect/neglect be tested using the extinction test?
A: - U can give a stimulus to either side of the pat, like a visual cue, noise or touch and the pat would be able to locate it to the right or to the left even if they had a partial neglet
- However if u would provide the stimuli simoultaneously to both sides the pat would extinct the one that is on the side affected by neglect, which is almost always the left side of the body

Q: How does neglect show in the activities of daily living?
A: U dont have to perform a formal test for neglect, u would also see it in the activities of daily living, some of the most obvi ex. is only shaving one side of head or eating half of the plate

Q: WHich areas of
the brain associated with hemispatial neglect, which involve large portions of
the right hemisphere, are there?
A: - Right parietal (A)
- Right superior temporal (B)
- Right dorsolateral prefrontal (C)

Q: What would be affected if there is a lesion in the prefrontal areas of the brain?
A: If there is a lesion in the prefrontal areas of the brain it affects the visual-motor apect of attentional control

Q: What is affected by a lesion in the right parietal region?
A: Perceptive/visuo-spatial component

Q: What is affected by a lesion in the right superior temporal region?
A: Allocentric/object-centered component

Q: What is affected by a lesion in the right dorsolateral region?
A: Exploratory/visuo-motor component

Q: What can enhance activity in the visual cortex in particular V4?
A: Activity in the frontal eyefield was able to enhance activity in the visual cortex in particular in V4
- Results presenting similar mechanisms in humans have been found using non-invasive methods

Q: What does FEF stand for?
A: Frontal Eye Fields

Q: What is the role of the FEF?
A: Top-down control of voluntary eye movements

Q: WHat can participants do when receiving inhibitory TMS to the FEF?
A: Participants performed a visual discrimination task requiring covert attention to one visual hemifield while MEG was recorded

Q: What was the result of the study where MEG recordings were plotted onto the brain?
A: - The TMS hindred the allocation of attention to the contralateral hemifield
- This was associated by the reduction of modulatory activity in the contralateral occipitoparietal cortex
- This means in the inhibition of frontal eye field it reduced its modualtory effect in the visual cotrex
- This shows non-invasively the frontal eye field is cautionly involved in the attention top-down control in the visual system

Q: What is the FEF involved in?
A: The frontal eye field is cautionly involved in the attention top-down control in the visual system

Q: WHat does inhibition of the FEF do?
A: The
inhibition of frontal eye field it reduced its modualtory effect in the visual
cotrex

Q: What did the use of TMS lead to, regarding FEF?
A: - Slowing of response times to contralateral targets
- Reduction of alpha band modulation in the contralateral occipitoparietal cortex

Q: What have different functional components involved in neglect led to?
A: The differnet functional components involved in neglect and also in the healthy human brain has been a lot of effort to find the brain regions involved in attentional control: led to the proposal of 2 networks

Q: Which Networks are i  nvolved in attentional control?
A: - Dorsal attention network
- Ventral attention network

Q: Which regions are involved in the dorsal attention network?
A: - Frontal Eye Field (FEF)
- IPS

Q: Which functions is the dorsal attention network involved in?
A: - Involved in goal-directed, voluntary control of visuospatial attention
- Top-down selection of stimuli and responses

Q: What selection of stimuli is related to the dorsal attention network?
A: Top-down selection of stimuli and responses

Q: What selection of stimuli is related to the ventral attention network?
A: Bottom-up selection of external stimuli

Q: Which regions are involved in the ventral attention network?
A: - MFG (middle frontal gyrus?)
- IFG (inferior frontal junction?)
- TPJ

Q: What does the ventral attention network respond to?
A: Responds to unexpected or salient external stimuli

Q: What's another name of the ventral attention network?
A: Salience network

Q: When is the ventral attention network more involved?
A: Is more involved when bottom
up selection of external stimuli is required

Q: When is the dorsal attention network more active?
A: This network is particulary active when ever top down selection of stimuli and responses is required

Q: Where is the ventral attention network located?
A: This is the part of the attention network that is lateralised to the right hemisphere, is showing in hemispatial neglect

Q: What is the ventral attention network showing in?
A: Is showing in hemispatial neglect

Q: What can be said about the relationship between the dorsal and ventral attention networks?
A: There is ofc dynamic interaction between the networks, its also possible to switch between the attentional networks, and the switches seem to be configured by the inferior frontal junction (IFG)

Q: How are shifts between the dorsal and ventral attentional networks conducted?
A: Attentional shifts configured by the inferior frontal junction (IFG)

Q: Whta can be said about determining who or what decides where we direct our attention?
A: There are some brain regions inolved in these networks that are essential for attention, however, It is very difficult who or what decides where we direct our attention

Q: How can paying attention be a whole-brain effort from start to finish?
A: - Input from all sensory modalities
- Integration via thalamus and parietal and temporal association cortices
- Higher-order processing in the prefrontal cortex

Q: How is attention further modulated?
A: Further modulated by arousal, affective and motivational state, memory, goals, reward,...

Q: Via which structures do we direct our eye movements?
A: - Directing eye movemenys via frontal and parietal eye fields as well as brainstem gaze-control centres
- Modulatory loops with sensory cortices

Q: Is there a region in the brain taht is considered the controller of our attention?
A: No one region in the brain seems to be capable of being the controller

Q: What is meant by no region being the controller of attention?
A: i.e. able to continuously integrate all inputs and to initiate and execute the appropriate reactions and behaviours (i.e. the output) by itself

Q: Is there and executive controller? Who decides where we direct our attention?
A: Its a fundamental question touching the definition of self and free will, hwoever, it seems unlikely

Q: What are some conecpts involving how the centralisation of this process of directing attention is done?
A: They are using:
- Integrational nodes that receive biasing signals from many regions (relative decentralisation)
- Saliency maps in association cortices correspond to different locations in space and can be activated by biasing signals
- Computational modelling: attention as a refelxive system shaped by trial and error-learning of pre-existing response sets over evolutionat and individual time

Q: How do saliency maps involve the centralisation of attention control?
A: Saliency maps in association cortices correspond to different locations in space and can be activated by biasing signals

Q: What is computational modelling?
A: Attention as a reflexive system shaped by trial and error-learning of pre-existing response sets over evolutional and individual time

Q: What can generally be said about computational power of the brain?
A: Computational power of the brain is limited, so
attention must always be selective

Q: What can generally be said about what claims our attention?
A: Indefinite numbers of external and internal stimuli claim our attention every second

Q: What can generally be said about "paying attention"?
A: Paying attention can be a voluntary or reflexive process, overt
vs convert, exogenous vs endogenous attention

Q: What can generally be said about top-down and bottom-up processes involved in attention?
A: An interplay between bottom-up and top-down processes, organized in 2 functional networks, directs the allocation of processing resources, with the ultimate goal to optimally guide behavior

Q: What is the ultimate goal with attention?
A: The ultimate goal is to optimally guide behavior

Q: What does the interplay between top-down and bottom-up do in attention?
A: There is always an interplay of bottom-up and top-down processes whichh handle the sensory inputs from stimuli and these areas oif the brain are orginised in 2 functional networks