Attention and consciousness

Question 1

What is selective attention, and how does it relate to sensory input?

Answer 1

Selective attention allows us to focus on one aspect of sensory input while ignoring others, helping us concentrate on specific objects or information in our environment.

Question 2

What is consciousness, and how is it related to attention?

Answer 2

Consciousness refers to awareness, and it is closely linked to attention, as we are generally aware of what we pay attention to. However, attention and consciousness are distinct processes.

Question 3

Is resting state brain activity consistent across different tasks?

Answer 3

Yes, resting state brain activity appears to be consistent even when the nature of the task is changed. Areas that show decreased activity during tasks are consistently active at rest.

Question 4

What brain areas make up the default mode network (default network)

Answer 4

Medial prefrontal cortex, posterior cingulate cortex, posterior parietal cortex, hippocampus, and lateral temporal cortex.

Question 5

What does the default mode network indicate when the brain is not engaged in an overt task? What are some activities associated with the inner life of the brain that may be related to the default mode network?

Answer 5

-The brain defaults to activity in this group of interconnected areas when it is not engaged in an overt task.
-Activities like daydreaming, remembering, and imagining, often referred to as spontaneous cognition

Question 6

What are the two hypotheses related to the function of the default network?

Answer 6

The two hypotheses are the sentinel hypothesis and the internal mentation hypothesis

Question 7

Explain the sentinel hypothesis related to the default network’s function.

Answer 7

The sentinel hypothesis suggests that even during rest, the brain must broadly monitor the environment as if it’s always “on the lookout.” This could be a result of evolution in a world with constant threats.

Question 8

How does the default network’s activity change when a person switches from rest to a peripheral vision task compared to a foveal vision task?

Answer 8

The default network’s activity decreases less when switching from rest to a peripheral vision task, indicating that it might be involved in diffusely monitoring the broad visual field

Question 9

What is simultagnosia, and how is it related to the sentinel hypothesis?

Answer 9

Simultagnosia is a disorder in which individuals can perceive individual objects but struggle to integrate simultaneous information to understand complex scenes. This condition is related to the sentinel hypothesis because the posterior cingulate cortex, a part of the default network, may play a role in diffusely monitoring the visual field for stimuli, which is disrupted in simultagnosia.

Question 10

What does the internal mentation hypothesis suggest the default mode network supports? How does the hypothesis explain the brain’s response to memory tasks compared to control tasks? What is the contrast in brain activity between autobiographical memory tasks and control tasks in the experiment? and which brain regions are activated when recalling past events and imagining new ones according to the experiment?

Answer 10

-The default mode network supports thinking and remembering, especially daydreaming during quiet moments or thinking about future.
-The hypothesis suggests that memory tasks activate the brain in a manner similar to daydreaming about one’s life, unlike the structured use of facts in control tasks.
-Autobiographical memory tasks activate the hippocampus and neocortical areas in the default network, while control tasks do not activate these brain areas.
-Recalling past events and imagining new ones activate similar regions of medial prefrontal and posterior cingulate cortex.

Question 11

describe the overall hypothesis of default network activity

Answer 11

The overall hypothesis is that, when the situation requires us to become actively involved in a perceptual or motor task, we switch modes from sentinel and internal mentation activities (high default network activity) to focused processing of sensory input (low default network activity and increased sensory–motor activity)

Question 12

What is the “cocktail party effect”?

Answer 12

The cocktail party effect is the ability to focus on one conversation or sound source while ignoring other surrounding noises or conversations in a noisy environment.

Question 13

How is selective attention different from overall arousal?

Answer 13

Selective attention is directed at specific objects or information, whereas overall arousal is a general state of alertness that is not selective.

Question 14

What is exogenous attention? example of exogenous attention?

Answer 14

-Exogenous attention, also known as bottom-up attention, is when attention is automatically drawn to a stimulus due to distinctive visual features like color, movement, or flashing lights.
-An example of exogenous attention is when a bright-yellow dandelion in a field of green grass automatically grabs your attention because of its distinctive color.

Question 15

What is endogenous attention? an example of endogenous attention?

Answer 15

-Endogenous attention, also known as top-down attention, is when attention is deliberately directed by the brain to a specific object or place to achieve a behavioral goal
-An example of endogenous attention is when you search for a specific passage in a book by deliberately focusing your attention on the upper-right corner of a page.

Question 16

What is covert attention?

Answer 16

Covert attention is the term used to describe the act of shifting attention to objects imaged on parts of the retina outside the fovea without moving the gaze.

Question 17

What is the fovea?

Answer 17

The fovea is the central, highest-resolution area of the retina where vision is sharpest, and it’s where we typically focus our gaze when scrutinizing something.

Question 18

What was the advantage of using cues in the experiment? How did observers perform when the cue pointed right but the target appeared to the left?

Answer 18

-using cues in the experiment allowed participants to strategically direct their attention to the likely target location, increasing the chances of correct responses.
-When the cue pointed right but the target appeared to the left, observers detected the target stimulus to the left in only about 50% of the trials where one was presented there.

Question 19

What was the effect of the arrow cue on reaction times when it correctly indicated the target location?

Answer 19

Reaction times were 20–30 milliseconds faster when the arrow cue correctly indicated the target location.

Question 20

Where are the effects of attention observed in the brain?

Answer 20

The effects of attention can be observed in various sensory areas, including the lateral geniculate nucleus (LGN) and visual cortical areas in the parietal and temporal lobes

Question 21

What happens in the brain when the location of the attended sector changes during visual attention tasks?

Answer 21

Brain activity associated with attention shifts retinotopically, even though the visual stimuli remain the same regardless of the attended sector’s location.

Question 22

How does focusing on specific visual features, like color, affect our ability to detect objects?

Answer 22

Focusing on specific visual features, such as color, can enhance our ability to detect and identify objects.

Question 23

What is the difference between selective-attention experiments and divided-attention experiments? this was done using PET scans

Answer 23

In selective-attention experiments, subjects focus on one specific feature (e.g., shape, color, or speed), while in divided-attention experiments, they monitor all features simultaneously. The brain activity associated with attention to one feature is isolated by subtracting divided-attention responses from selective-attention responses.

Question 24

Which areas of the cortex had higher activity during different stimulus discrimination tasks?

Answer 24

Ventromedial occipital cortex was affected by attention in color and shape discrimination tasks, while parietal cortex was influenced by attention to the motion task.

Question 25

Were areas in parietal cortex affected by attention in color and shape discrimination tasks?

Answer 25

No, areas in parietal cortex were influenced by attention to the motion task but not the color and shape discrimination tasks.

Question 26

Which areas of the cortex showed heightened activity during color and shape discrimination tasks?

Answer 26

areas of heightened activity in color and shape discrimination tasks may have corresponded to areas like V4 and IT (interior temporal gyrus) and other visual cortical areas in the temporal lobe.

Question 27

Which area was most affected by performing the motion task? or speed of motion

Answer 27

The area most affected by performing the motion task was near area MT (middle temporal) of visual cortex.

Question 28

What is the time difference between shifts in attention and saccadic eye movements?

Answer 28

Shifts in attention can occur in about 50 milliseconds, while saccades take about 200 milliseconds.

Question 29

In the experiment conducted by Wurtz, Goldberg, and Robinson, what did they observe about the response of parietal neurons to a flashed stimulus? What does the enhanced response of neurons in the posterior parietal cortex suggest about attention and eye movements? What is the alternative interpretation considered regarding the enhanced response of neurons in the parietal cortex?

Answer 29

-Parietal neurons were excited by the flashed stimulus in their receptive field, and the response was significantly enhanced when the monkey made a saccade to foveate it.
-The enhanced response suggests that attention moves to the end of the planned saccade before the eyes move, and only neurons with receptive fields at that location have responses enhanced by the attention shift that precedes the saccade.
-The alternative interpretation is that the enhanced response was a premotor signal related to coding for the subsequent eye movement, similar to how neurons in motor cortex fire before hand movements.

Question 30

How did the researchers address the possibility that the enhanced response was related to coding for subsequent eye movements?

Answer 30

the researchers performed a variation of the experiment in which the animal moved its hand rather than its eyes to indicate the location of the peripherally flashed stimulus. Even without a saccade, there was an enhanced response to the target in the receptive field, suggesting that, rather than a premotor signal, the enhanced response was a result of an attention shift needed to accurately perform the task.

Question 31

What did Robert Desimone and his colleagues study in their experiments and what was the purpose of the same-different task in their experiments?? How did the V4 neurons respond to effective and ineffective stimuli? What happened when the monkey attended to the receptive field area with ineffective stimuli? How did attention affect the neural activity in the experiment?

Answer 31

-They studied the effects of attention on the receptive fields of neurons in visual cortical area V4. The monkeys had to judge whether pairs of stimuli presented in the receptive fields of V4 neurons were the same or different.
-The responses of V4 neurons were reduced even when the same stimuli were presented, as if the receptive field contracted around the attended area.
-Attention had a location-specific effect, reducing the neural response in the receptive field area containing ineffective stimuli, even when the stimuli were identical.

Question 32

What role do saccadic eye movements play in guiding attention?

Answer 32

Saccadic eye movements play a critical role in guiding attention, and humans tend to saccade to objects that are salient or of behavioral interest.

Question 33

What is the pulvinar nucleus of the thalamus known for in attention? How do pulvinar neurons respond in the presence of attention to a stimulus?

Answer 33

-The pulvinar nucleus of the thalamus is known for its possible role in guiding attention.
-Pulvinar neurons respond more robustly when an individual attends to a stimulus in the receptive field compared to when attention is directed elsewhere.

Question 34

What kind of connections does the pulvinar have with various brain areas?

Answer 34

The pulvinar has reciprocal connections with most visual cortical areas of the occipital, parietal, and temporal lobes, allowing it to potentially modulate widespread cortical activity.

Question 35

What happens in monkeys when attention is drawn to a pulvinar receptive field?

Answer 35

In monkeys, when attention is directed to a pulvinar receptive field, there is increased synchronization between neural activity in the pulvinar, area V4, and area IT, suggesting that the pulvinar regulates information flow in visual cortex areas.

Question 36

What deficits have been observed in humans with pulvinar lesions?

Answer 36

Humans with pulvinar lesions respond abnormally slowly to stimuli on the contralateral side, especially when there are competing stimuli on the ipsilateral side. This suggests a reduced ability to focus attention on objects in the contralateral visual field.

Question 37

What effect does the injection of muscimol, an agonist of GABA, have on the pulvinar’s activity and attention? What effect does the injection of the GABA antagonist bicuculline have on attention?

Answer 37

-Unilateral injection of muscimol into the pulvinar suppresses the activity of pulvinar neurons and produces difficulty in shifting attention to contralateral stimuli. This effect is similar to the impact of pulvinar lesions in humans.
-Injection of the GABA antagonist bicuculline appears to facilitate shifting attention to the contralateral side.

Question 38

What is the frontal eye fields (FEF) in the brain?

Answer 38

The frontal eye fields (FEF) are a cortical area in the frontal lobe of the brain.

Question 39

What is the function of neurons in the FEF?

Answer 39

Neurons in the FEF have motor fields in the visual field and can trigger eye movements when stimulated.

Question 40

How did Tirin Moore and colleagues study the FEF’s role in attention?

Answer 40

They trained monkeys to fixate on a central point while paying attention to a specific spot among distracter spots. They measured the monkey’s ability to detect changes in the target spot’s brightness, varying the difficulty of the task.

Question 41

What was the aim of the experiment involving electrical stimulation in the monkey’s FEF (Frontal Eye Field)? What were the results of the experiment involving electrical stimulation in the FEF?

Answer 41

-The aim was to determine whether small electrical stimulation in the FEF could enhance the monkey’s ability to detect dimming of a target spot, acting as an artificial attentional boost.
-When the target stimulus was located inside the motor field, electrical stimulation reduced the threshold light difference needed to detect dimming of the target by about 10%. However, performance was not enhanced and may have been impaired by electrical stimulation if the target was outside the motor field.

Question 42

How did the effects of electrical stimulation in the FEF compare to attentional modulation?

Answer 42

Electrical stimulation in the FEF improved performance in a manner similar to added attention, and the effect of electrical stimulation was location-specific, just like attentional modulation.

Question 43

What hypothesis did Moore et al. test regarding the role of the FEF in directing attention?

Answer 43

They tested the hypothesis that FEF activity indicating the location of a potential future saccadic eye movement feeds back to connected cortical areas, enhancing activity there.

Question 44

What did Moore’s research group observe when recording from area V4 during electrical stimulation of the FEF? What do Moore’s experiments suggest about FEF stimulation?

Answer 44

-When the FEF was stimulated (with a current insufficient to evoke a saccade), the visual response of the V4 neuron was increased compared to trials without FEF stimulation. This increase in V4 activity was an enhancement of a visual response.
-FEF stimulation mimics both physiological and behavioral effects of attention.

Question 45

What does a salience map show in the context of attention?

Answer 45

A salience map shows the locations of conspicuous features in the visual field.

Question 46

How does a salience map differ from a map showing the locations of objects? What is the function of the salience map in the salience map model?

Answer 46

-A salience map locates areas of high feature contrast, regardless of specific features, while a map showing object locations focuses on the locations of specific objects.
-The salience map locates areas of high contrast irrespective of specific features and determines the winning location to which attention is directed

Question 47

What is the first stage in the salience map model? How does the competition process work within a feature map in the salience map model?

Answer 47

-The first stage consists of maps of individual features that locate areas of high feature contrast, such as changes in orientation, color, or motion.
-Competition within a feature map may suppress responses associated with lower feature contrast.

Question 48

What prevents attention from getting stuck at the single most salient location in the salience map model?

Answer 48

“Inhibition of return” prevents successive attentional loci from being the same.

Question 49

What is the limitation of the salience map model as initially described?

Answer 49

The initial model accounts only for bottom-up guidance of attention, not top-down attentional modulation

Question 50

How can top-down attentional modulation be added to the salience map model?

Answer 50

Top-down attentional modulation can be added by inserting top-down cognitive input to either the feature maps or the salience map, specifying attentional priorities based on cognitive factors.

Question 51

What is a priority map in the context of attention?

Answer 51

A priority map is a map showing locations where attention should be directed based on stimulus salience and cognitive input, combining bottom-up salience with top-down attentional priorities.

Question 52

What is the role of the lateral intraparietal cortex (area LIP) in attention?

Answer 52

Area LIP constructs a priority map based on both bottom-up and top-down inputs. It plays a crucial role in directing eye movements, which is related to the guidance of attention

Question 53

What is the neglect syndrome associated with lesions in the parietal cortex?

Answer 53

The neglect syndrome is characterized by an inability to attend to half of the environment. It is often associated with lesions in the parietal cortex.

Question 54

Describe the salience effect observed in LIP during an experiment.

Answer 54

In an experiment, a monkey’s LIP neuron responds vigorously when a conspicuous stimulus, such as a star, is turned on just before it enters the neuron’s receptive field. This effect suggests the presence of a salience map in area LIP. Without something like a flash to increase its salience, the LIP neuron does not respond much to the star in its receptive field. LIP neurons carry information that is appropriate for a priority map of visual attention.

Question 55

What is the first critical step in the bottom-up attention process?

Answer 55

In the bottom-up attention process, the first critical step may be the construction of a salience map based on conspicuous objects in the field of view. Input from visual areas in the occipital lobe reaches area LIP. Visual processing is enhanced; eyes may move

Question 56

Which brain areas are involved in top-down control of attention? and describe it

Answer 56

-Top-down control of attention involves cortical areas in the frontal lobe, including the prefrontal cortex and the frontal eye fields.
-Attention effects follow a temporal sequence, occurring first in the frontal lobe (prefrontal cortex and the frontal eye fields) and followed progressively by areas LIP, V4 and MT, V2, and then V1.
-Visual processing is enhanced; eyes may move

Question 58

What is the role of brain areas like LIP, FEF, and the superior colliculus in attention?

Answer 58

Brain areas like LIP, FEF, and the superior colliculus serve to guide saccadic eye movements to scrutinize the objects allocated attention.

Question 59

What is the materialist view of consciousness?

Answer 59

The materialist view suggests that consciousness arises from physical processes and can be understood based on the structure and function of the nervous system.

Question 60

What is dualism regarding consciousness?

Answer 60

Dualism posits that the mind and body are distinct entities that cannot be fully explained by each other, meaning that consciousness cannot be fully explained by physical processes.

Question 61

What is the distinction proposed by David Chalmers regarding consciousness?

Answer 61

David Chalmers proposed the distinction between the “easy problems” and the “hard problem” of consciousness.

Question 62

What are the “easy problems” of consciousness according to Chalmers?

Answer 62

The “easy problems” of consciousness are phenomena that seem answerable by standard scientific methodology, such as understanding the difference between being awake and asleep or studying attention.

Question 63

What is the “hard problem” of consciousness? Why is the “hard problem” of consciousness considered challenging?

Answer 63

-The “hard problem” of consciousness refers to the experience itself, such as subjective experiences like happiness, the perception of colors, or emotional responses. It involves understanding why and how these subjective experiences arise from physical processes
-The “hard problem” of consciousness is challenging because it involves understanding why subjective experiences have the specific qualities they do, and it goes beyond identifying neural activity associated with these experiences

Question 64

What is the definition of neural correlates of consciousness (NCC)? What experimental approach has been taken to study changes in brain activity related to changes in perception? What is the key question in studying bistable images and changes in brain activity?

Answer 64

-NCC is defined as the minimal neuronal events sufficient for a specific conscious percept.
-Visual images presented as bistable images, where the same image can be seen in two different ways, are used to investigate changes in neural activity correlated with shifts in perception.
-The question is about what happens to brain activity when a person or animal switches from one percept to another when viewing bistable images.
-this is experimentally demonstrated –> neural recordings in monkey area IT show changes correlated with perceptions. and neural activity in IT may be neural correlate of this awareness

Question 65

What is binocular rivalry? How does binocular rivalry work?

Answer 65

-Binocular rivalry is a visual effect where different images are seen by each eye, and perceptual awareness alternates between the two images.
-In binocular rivalry, if one eye sees one image, and the other eye sees a different image, a person will perceive alternating experiences between the two images.

Question 66

Describe an experiment involving binocular rivalry. What did the neural recordings in the inferotemporal cortex reveal during the binocular rivalry experiment?

Answer 66

-An experiment recorded neural activity in the inferotemporal cortex (area IT) while a monkey alternated between perceiving starbursts and monkey faces based on visual stimuli presented to each eye.
-The neural recordings showed that the activity of IT neurons fluctuated between low and high levels in sync with the monkey’s perception of either starbursts or monkey faces, even though the visual stimuli remained constant.

Question 67

What is the implication of the neural–perceptual correspondence observed in binocular rivalry experiments? In which brain areas was the neural–perceptual correspondence more common during binocular rivalry experiments?

Answer 67

-The correspondence suggests that neural activity in IT may be a neural correlate of conscious awareness, indicating a link between changes in neural activity and perception.
-The neural–perceptual correspondence was relatively uncommon in early brain areas like V1 and V2 but became almost universal in area IT, leading to speculation that early areas are less likely to be part of a neural correlate of consciousness (NCC).

Question 68

What areas of the brain were recorded during rivalry experiments in the temporal lobe? What patterns of brain activity were observed in FFA and PPA during rivalry conditions?

Answer 68

-The fusiform face area (FFA) and the parahippocampal place area (PPA) in the temporal lobe were recorded during rivalry experiments.
-In rivalry conditions, there were alternating patterns of brain activity in FFA and PPA during transitions between perceiving faces and houses.
-Alternating patterns of brain activity in FFA and PPA can occur during constant visual input, suggesting their role as neural correlates of consciousness (NCC) for faces and houses.

Question 69

What is the fusiform face area (FFA) known for? What does the parahippocampal place area (PPA) respond to?

Answer 69

-The FFA is known for responding preferentially to pictures of faces.
-The PPA responds to pictures of houses and other places but not to other classes of stimuli.

Question 70

How did the entorhinal neuron respond during imagery compared to visually evoked responses? What does this experiment suggest about the entorhinal cortex’s role in neural correlates of consciousness (NCC)?

Answer 70

-The entorhinal neuron showed more activity when the person imagined the dolphin photo than the face photo during imagery.
- This experiment raises the possibility that the entorhinal cortex may be part of an NCC, given its distinct responses during imagery.

Question 71

What challenges are associated with interpreting consciousness studies?

Answer 71

Contamination of neural activity, coordination of NCCs across multiple areas, and the relationship between attention and awareness.

Question 72

What challenges of interpreting NCC study data

Answer 72

-What is “minimal” brain activity sufficient for
conscious experience?
–Is the neural activity a prerequisite for conscious experience or consequence of the experience but not NCC?
–Can attention be confounded with awareness?