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8 Cards in this Set
- Front
- Back
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What has the assumption been in the topics discussed so far? However, what is wrong with this? What do people usually do? What is attention? Why is it important? How does William James describe attention? What does normal attention cause? |
When a stimulus is imaged onto the retina, it is processed by neurons in specialised regions of the visual cortex leading to perception. People do not always sit passively whilst stimuli is presented. Take an active role in their perception by seeking out interesting or important stimuli. Taking notice of something or someone interesting or important. It directs us to stimuli we want to perceive and influences the way information is processed. As the act of taking possession in the mind in a clear and vivid form of one out of several possible stimuli, objects or trains of thought. Things which we attend to to become clearer and more vivid whilst causing the things we don't attend to to never enter our perceptual experience. |
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What is inattentional blindness? What is it also known as? Describe a study which provides evidence for inattentional blindness. What is the attentional blink? What is the evidence for the attentional blink? |
Describes the event of an individual failing to recognise an unexpected stimulus that is in plain sight. Perceptual blindness. Participants were asked to indicate which arm of a cross was larger. On the inattentional trial, a small object was added to the display. Subjects were asked which objects did you see. Performed significantly poorly when they are not paying attention (Gorilla study). The inability to see a 2nd target stimulus that is presented as one of a string of briefly flashed stimuli. A study briefly presented subjects with a string of letters with 1 number in the mix. Students had to indicate the number when it was presented. However, the 1st target was a number 2, a number of additional letters were presented followed by a number 7. If the time between targets is less than 0.5 seconds, subjects will nearly always fail to detect the 2nd number. |
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What is change blindness? What does change blindness demonstrate? How do studies measure this? What do inattentional blindness, the attentional blink and change blindness all illustrate? How do we direct our attention? What did Helmholtz observe? What does enhancing perception compromise? |
The inability to detect unattended changes in the environment. Unless we pay attention we are not aware of much of what we see. Flash 2 images that differ slightly such as a slight movement location or colour change which will often go undetected unless our attention is drawn to this feature. The importance of attention in visual perception. Using an attentional spotlight. We can enhance attention by focusing our attention on a location in the visual field. The acuity of other areas. |
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What is covert attention? What is the spotlight theory of attention? What evidence has been found for this? |
Shifting the attentional spotlight to enhance attention but in the absence of an eye or head movement. The ability to voluntarily direct attention to a specific part of the visual field in a similar effect to that of a spotlight which increases efficiency for signals at that location to be processed. An experiment told participants an object would flash on a screen and they must indicate when they had seen it. Participants were either told the correct/incorrect/neutral position where the shape would appear.It found that the fastest detection was when they were told the correct location of the object, followed by neutral, followed by wrong. |
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What can be used to determine the biological effects of attention? Describe a study. What is voluntary attention also known as? What things are exogenous? |
ERPs to record activity of neurons from the scalp of humans. Participants were asked to attend to left or right of a screen whilst the stimulus appeared on the left side. Trials where the target was presented to the attended side caused a larger ERP than when it was presented to the unattended side, despite the images being identical. Endogenous attention. Things that are in our environment that automatically attract our attention. |
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What will enhance perception of a target? On what condition? What have ERPs attempted to find? What did they find? Where else can visuospatial attention be found? Describe a study which investigates this. |
A cue. If the target is presented within 0.3seconds of a cue but if a target is presented at a longer delay, an impairment occurs. Neural correlates of exogenous attention. That cueing increases the size of an ERP but only if the target appears within 0.3seconds. Neurons in the visual cortex. The study measured the effect of selective attention on the response of a neuron in area V4 which responds to blue vertical shapes in the lower visual field. It found when attention is diverted to the location where the preferred stimulus is, a large response is recorder. However, when attention is diverted to a different location (but still within the receptive field) the neuron fires less. Higher firing occurs when attention is fixed on the object despite the same visual field stimulation. |
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What else can attention influence? Describe a study. What was the result? What does it show? |
Firing of neurons in the dorsal stream. Participants fixated eyes on a dot, a light was then presented within the receptive field of a neuron within the parietal lobe. In the fixation condition, there was no attentional task but in the fixation and attention condition, attention is diverted to a light. Neurons response is different in these 2 conditions even though the light within the receptive field of the neuron is identical in both conditions. Attention affects perceptual processing by increasing the response of neurons (higher in fixation and attention). |
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What is neglect? What can patients still see? What have neuroimaging studies of attention found? What happens if we want to scrutinise something visually? What is the feature search task? What is the conjunction search task? What is found in the feature search task? What is found in the conjunction search task? What is it possible to attend to? What happens to the visual cortex when different features or objects are attended to? What has attention to movement been found to increase? |
Disorder of attention where lesions to the right parietal lobe result in patients neglecting objects in their left visual field. Surroundings in the left visual field when attention is directed to it, they just neglect to attend to it. Right parietal lobe plays an important role in switching attention between objects. Move our head so that the object of interest is imaged onto the fovea in each eye. Participants must pick out a target among distractors differentiated by a single property such as colour, shape or size. Detecting a target among distractors which is similar in more than 1 visual property i.e. colour, shape, size or orientation. Time to detect the presence of a target is independent of display size. The type of task is pre-attentive as it does not require shifting attention. Reaction times increase as a function of display size which suggests we are shifting our attentional spotlight to different areas of the display. One feature within the visual scene such as colour or shape but at the expense of detecting change in other features. Becomes active, e.g. when a subject focuses on colour, responses in V4 increase. Increased processing/activation in V5/MT and increased attention in the FFA when attention is drawn to faces. |
