Attention PDF

Here are some ashcards with information from the sources: What is Attention? Attention (or selective attention) is the intentional focus on speci c stimuli, whether sensory phenomena or internal thoughts, for enhanced processing and analysis. Overt attention is when the focus of our senses...

Here are some ashcards with information from the sources: What is Attention? Attention (or selective attention) is the intentional focus on speci c stimuli, whether sensory phenomena or internal thoughts, for enhanced processing and analysis. Overt attention is when the focus of our senses and attention are directed at the same target. Covert attention is the ability to shift the focus of visual attention without moving the eyes. The cocktail party effect, the ability to selectively listen to one speech-related frequency, is an example of auditory attention. What are the Different Types of Attention? Sustained attention is the ability to focus on speci c stimuli over a long period of time. Auditory attention is the ability to focus on speci c sounds while ignoring distractions. Voluntary attention is the voluntary direction of attention towards a speci c stimulus, in accordance with interests and goals. Re exive attention is the involuntary shifting of attention toward the location of an unexpected stimulus. What is Arousal? Arousal is a global physiological and psychological brain state. Arousal is best thought of as a continuum, ranging from deep sleep to hyper alertness. What are Attentional Phenomena? Attentional phenomena are key characteristics of attention. Examples include the ability to voluntarily choose the focus of attention, the inability to attend to many things at once, and the selective aspects of attention. What is Information Overload? Information overload occurs because we are surrounded by more information than we can handle and comprehend at any given time. The nervous system has to make decisions about what information to process, and survival may depend on which stimuli are selected and the order in which they are prioritized. What are Attention Tasks? Dichotic presentation is a method for studying attention. Two distinct streams of speech are delivered through headphones to the right and left ear, and participants are instructed fl fl fi fi  to concentrate on one ear and repeat the information aloud. This process is called shadowing. In the line cancellation test, patients are given a sheet of paper with many horizontal lines and are asked to bisect the lines precisely in the middle with a vertical line. This is a neuropsychological test used to diagnose neglect. What is Balint’s Syndrome? Balint’s Syndrome is a condition caused by bilateral damage to regions of the posterior parietal and occipital cortex. People with Balint’s Syndrome experience a severe disturbance of visual attention and awareness, in which only one or a small subset of available objects is perceived at any one time and objects are mislocalized in space. They can “see” each object presented, but fail to see them all together and cannot accurately describe their locations with respect to each other or to themselves. What is the Feature Integration Theory? The feature integration theory proposes that we coordinate our search by looking for one basic stimulus feature (e.g. color, shape) at a time. Searching for one feature at a time is a bottom-up process. Searching for multiple features at once is a top-downprocess. What is Neglect? Unilateral spatial neglect, or neglect, results when the brain’s attention network is damaged in one hemisphere, typically due to a stroke. More severe effects occur when the right hemisphere is damaged. People with neglect experience a bias in attention toward the right, resulting in a neglect of what is going on in the left visual eld. They behave as if the left regions of space and the left parts of objects do not exist and have limited or no awareness of their lesion and de cit. Neglect can be overcome if the patient's attention is directed to the neglected locations or items. Extinction is a prominent feature of neglect. It is the failure to perceive or act on stimuli contralateral to the lesion (contralesional stimuli) when presented simultaneously with a stimulus ipsilateral to the lesion (ipsilesional stimuli). What In uences Attention? fi fl fi  Stimulus salience: Sudden stimuli like loud noises, ashes, and moving objects can cause re exive attention. Goal-directed behavior: Intentionally searching for features, like when looking for a person in a crowd, is an example of voluntary attention and a top-down process. Dif culty of a task/stimuli: Attention is in uenced by the dif culty of a task, according to the early/late-selection model. Experience: Experience can change the way our brains process information (e.g. type 1 & 2 thinking). Brain damage: Balint’s Syndrome is an example of how brain damage can in uence attention. Subcortical Regions Involved in Attention Superior Colliculus: Located in the midbrain, the superior colliculus receives visual inputs and is involved in directing eye movements, especially for overt attention. It is more active when eye movements are made toward attended stimuli instead of eye movements without attention. Pulvinar: The pulvinar is located in the posterior quarter of the thalamus. It is deeply involved in visual processing and is important for orienting attention and ltering out distractions. It plays a role in covert attention and is highly active during attention tasks with many distractions. Cortical Regions Involved in Attention Dorsal Frontoparietal Network: Responsible for the top-down, voluntary control of attention. ○ Lateral Intraparietal Area (LIP): Region in the monkey parietal lobe, homologous with the human intraparietal sulcus. ○ Intraparietal sulcus (IPS): Located in parietal lobe, the IPS is especially involved in voluntary, top-down control of attention. ○ Frontal eye eld (FEF): Located in the frontal lobe, the FEF contains neurons important for controlling eye movements and ensuring that gaze is directed according to cognitive goals, which is a top-down process. Right Temporoparietal Network: Crucial for bottom-up processes and re exive attention. ○ Temporoparietal Junction (TPJ): Located at the junction of the temporal and fi fl fi fl fl  parietal lobes, primarily in the right hemisphere, the TPJ sends an “alerting signal” disrupting the current attentional focus when new, unexpected, and potentially important stimuli occur. ○ Ventral frontal cortex (VFC): Associated with working memory, the VFC helps identify novelty. What is ADHD? Attention de cit hyperactivity disorder (ADHD) is the best-known disorder of attention. It is characterized by disturbances in neural processing that may result from anatomical variations of white matter throughout the attention network. Structural MRI studies have found decreased white matter volume throughout the brain in people with ADHD, especially in the prefrontal cortex. Effects of Attention on Brain Regions Attention increases the activity of brain regions responsible for processing the stimuli being attended to. For example, when focusing on FACES rather than HOUSES in superimposed images, the fusiform face area shows enhanced activity. If attention is directed to the HOUSE, there is enhanced activation in the parahippocampal place area. Attention and ERP Effects Auditory Attention: N1 effect & P3 effect Visual Attention: P1 effect Spatial Cuing Tasks Sustained-attention task: Task in which a single stimulus source/location must be held in the attentional spotlight for a speci c period of time. Symbolic cuing task (or spatial cuing task): A task in which a symbolic cue (e.g. arrow) indicates the location to which attention should be directed. Peripheral spatial cuing task: Similar to the symbolic cuing task, but the cue is a ash of light at the relevant location. What is the Binding Problem? The binding problem is the question of how the brain registers individual features to build an object since features are processed in different areas of the brain. Other Important Terms Vigilance: Level of alertness fi fi  Pop Out: Stimuli are said to “pop out” when they can be identi ed from among distractor stimuli by a simple single feature and the observer can nd the target without searching the entire array. Set Size: The number of items in an array. fi