Midterm 2 Flashcards
What is sound?
The air vibrates, and that information has to be transformed into a neural code to represent sound and speech
What is a pure tone?
A pure tone consists of only a single frequency. Its wave form is a pure sine wave
What is a complex tone?
A complex tone is a sound wave that repeats with a given pattern, BUT the pattern is not a sine wave
What is timbre?
Quality of auditory sensations produced by the tone of a sound wave. Two non-identical sounds can have the same loudness and pitch
What does timbre depend on?
Timbre depends on the frequency spectrum, the sound pressure and the temporal characteristics of the sound
What is a Shepard Tone?
An audio illusion that creates the feeling of consistent, never-ending rising/falling. The illusion is achieved by playing overlapping notes that are one octave apart
What is the human cochlea?
The cochlea is a hollow, spiral-shaped bone found in the inner ear that plays a key role in the sense of hearing and participates in the process of auditory transduction. Sound waves are transduced into electrical impulses that the brain can interpret as individual frequencies of sound
What is Tonotopy?
Tonotopic organization refers to the systematic topographical arrangement of neurons as a function of their response to tones of different frequencies
Where in Tonotopy found?
Along the basilar membrane in the ear and in the primary auditory cortex
Describe the neurons in the Secondary Auditory Cortex?
Neurons in the secondary auditory cortex represents a greater range of frequencies, loudness, location, and combinations of features
What is there a specialization for in the auditory region?
Speech, Music, and Voice Recognition
Describe the ventral stream?
WHAT you’re hearing. There’s some evidence that suggests there are selective processing regions (neurons) for some categories of sound
Describe the dorsal stream?
For where/how: Localization. There’s inter-aural time difference (loudness and timing): when your head is tilted, sound arrives at one ear before the other. Distortion: Sound will be more distorted if it occurs on the other side of your head
What is Overt Attention Eye Movements?
Head and eye movements can be employed to gaze directly at an item. This is often referred to as an overt shift of attention. It’s the most direct way to shift attention, but poor resolution in the periphery means that you are aware primarily of things near the center of gaze (fovea)
What is Covert Attention?
Attention directed to a location that is different from that on which the eyes are fixated
What is Endogenous attention?
Goal-driven attention is referred to as top-down or endogenous attention
What is Exogenous attention?
Stimulus-driven attention is referred to as bottom-up or exogenous attention, being driven by external events in the environment
Describe Exogenous (bottom-up) attention:
Feature/stimulus driven, “reflexive” or automatic, fast, and temporary
Describe Endogenous (Top-down)
Goal or experience driven, voluntary, slower, and can be persistent
Describe feature-based attention selection (hint: two):
“Preattentive” so single-feature, parallel, and versus. “Attentive” feautre integration and serial
Attention spreads….
Within objects more than between objects
What is the Cocktail Party problem?
The brain’s ability to focus one’s auditory attention on a particular stimulus while filtering out a range of other stimuli, such as when a party goer can focus on a single conversation in a noisy room
What is the correlation between all sensory systems and attention?
All sensory systems can be influenced by attention, and attention influences perception. For example, distraction and pain
Why is a hypothesis a liability?
A hypothesis drives attention towards specific patterns of data, and leads to missing other patterns
What are two deficits of attention?
Neglect and Balint’s Syndrome
What is spatial neglect?
They are generally defined as an inability to perceive, report and orient to sensory events towards one side of space, contralateral to the side of the lesion, with or without a primary sensory deficit
What is object-based neglect?
The impairment is called object-based visual neglect because the neglect is with respect to each object, and not to the visual field. Loss of attention or awareness to left side of OBJECT
What is brain region is relevant to space-centered neglect?
More dorsal regions: Inferior Parietal Lobe (IPL) and Temporal Parietal Lobe (TPL)
What brain region is relevant to object-centered neglect?
More ventral regions: Superior Temporal Gyrus
What is Balint’s Syndrome?
An inability to visualize more than one object in the visual field at a time (psychic paralysis of gaze or visual inattention). An inability to identify different items in a visual scene simultaneously (a spatial disorder of attention or simultagnosia). A failure to reach an object with his right hand but able to do so with the left hand (Misreaching or optic ataxia)
What are the two deficits of attention discussed in class?
Traumatic Brain Injury: Deficit of sustained attention and Multimedia use
What is frequency?
How many times a wave cycles every second (period). Shorter period = Higher Pitch, Longer period = Lower Pitch
What is amplitude?
How high the waves become. Smaller amplitude = Quieter, Larger amplitude = Louder
Give an overview of Auditory Pathway
1) There is energy in the world, in the form of air compression. 2) Sound waves enters the ear, get focused by the shape of the ear. 3) Receptors in cochlea transform into neural activity. 4) Signals transmitted down auditory pathway in brain
What are the four parts of the ear (ear structure)
Pinna, Ear Canal, Tympanic Membrane, 3 bones (stapes, maleus, incus)
What is the Pinna?
Focus sound into the ear canal
What is the Ear Canal?
Carry the sound further into the ear to tympanic membrane
What does the Tympanic Membrane do?
Vibrate in response to sound waves
What do the 3 bones (stapes, maleus, incus) do?
Carry information to cochlea
Describe the cochlea’s organization
Organized in a tonotopy meaning the cells at one end respond to the highest frequencies and cells at the other end respond to the lowest frequencies of sound waves, with a gradient in between
How does the cochlea transform sound waves into neural activity?
Cochlea is covered in hair cells. The movement of the fluid in the cochlea moves the hair cells. Movement of hair cells physically pulls open ion channels to start transduction of signal
What are cochlear implants and what does it do?
Partially restoring hearing in those with deafness caused by cochlea damage. Directly stimulate the auditory nerves to get information to the brain. The brain will partially rewire to interpret signals.
What is McGurk effect?
The McGurk effect is an illusion whereby speech sounds are often mis-categorized when the auditory cues in the stimulus conflict with the visual cues from the speaker’s face.
What does the McGurk effect show?
Integration of information across sensory modalities
Is the auditory system more sensitive to temporal or spatial information?
Temporal (changes relative to time). The auditory system is tuned to detect temporal information, such as rapid changes in frequency that characterize certain speech sounds, and in grouping information together over time, such as in extracting melody from music
What is the belt region?
Part of the secondary auditory cortex, with many projections from the primary auditory cortex
What is the Parabelt region?
Part of the secondary auditory cortex, receiving projections from the adjacent belt region
What is the anterior belt region sensitive to?
Specialization for “what” - pathway to ventral stream
What is the posterior belt region sensitive to?
Spatial selectivity “where” - pathway to dorsal stream
What is inattentional blindness?
A failure to be aware of a visual stimulus because attention is directed away from it
Change Blindness
A failure to notice the appearance/disappearance of objects between two alternating images
What is attention?
Attention is a mechanism that allows us to voluntarily suppress unnecessary information and focus on necessary information
What are the 3 modes of selection?
Location-based, Feature-based, and Object-based
Describe location-based selection
Attending to the location of an object
Describe Feature-based selection
Attending to features (color, shape, etc.) in an array of objects
Describe Object-based selection
Attending to a particular object (face vs. scene)
What are two ways to orient attention?
Covert attention and Overt Attention
What brain region is crucial for attention?
Parietal Lobe
What is LIP and why is it important?
Lateral intra-parietal area (LIP). In monkeys, LIP has both forward connection (to frontal eye fields, FEF, which can direct eye movements) and feedback connections that can impact lower levels of the system -> human homologue is intraparietal sulcus (IPS)
Describe LIP Neurons
LIP neurons have large spatial receptive fields that respond to input at a particular location. If something draws attention to the receptive field, activity in LIP increases
What does LIP compute?
LIP computes a salience map (map of behaviorally important parts of space), and activation in LIP can tell you where to direct attention and eye movements
Describe Parietal Neuron Experiments and Findings
Monkey stares at fixation, is taught that the target visual stimulus is a light. If monkey ignores the light, low activity in parietal neuron. If monkey moves its eyes when the light comes on, much stronger response in parietal neuron (responds even before monkey moves its eyes). Neuron still fires even if the monkey attends to the light without moving eyes (responds even before monkey reaches out its hand)
Describe V4 neurons
Have big receptive fields (can have multiple objects in one receptive field) and respond to certain color and shape combinations. V4 neuron response is modulated by attention, which relies on LIP
What does V4 respond to strongly in humans?
When attending to color (area V4 is sensitive to color)
What does MT respond strongly to in humans?
When attending to motion (area MT is sensitive to motion)
List and describe two deficits of attention
Inattentional blindness (gorilla awareness challenge) and change blindness (in a flickering display)
Damage to parietal lobe can result in Neglect and Balint’s Syndrome. Is this permanent?
No, both Neglect and Balint’s Syndrome tend to get better over time
What happens if one hemisphere of parietal lobes is damaged?
Damage to one hemisphere of parietal lobes (usually right side) leads to loss of attention or awareness (NOT blindness) to the side opposite of the lesion (“contralesional” side)
Describe Spatial Neglect
Damage to more dorsal regions (right IPL and TPJ) - closer to “where” pathway. Loss of attention/awareness to left visual space and side of the body
Describe Object-based neglect
Damage to more ventral regions (right STG) - closer to “what” pathway. Loss of attention/awareness to left side of an object
What evidence is there for spatial neglect?
Artist’s self-portrait. Line bisection. Visual search. Copying drawings. Number line bisection. Spatial neglect in imagery
What test proves that Neglect is not merely a perception problem (they are not blind in left visual field)
Extinction test. If experimenter puts a finger up in a neglected field, the patient can still accurately report it. If experimenter puts finger up in both fields, patient ignores contralesional side
Describe Object-based Neglect
Damage to right ventral region (closer to “what” pathway) - superior temporal gyrus. Responds to left side of space, but neglects left side of objects (object-centered frame of reference)
What is the evidence for Object-based Neglect
Rotated Objects and Word Representations
Describe Balint’s Syndrome
Bilateral parietal damage. Loss of attention or awareness to both sides of space (attentional “tunnel vision”) - can only report seeing one object at a time. Perception depends on how they construe an object
How does Klaus Scherer define Emotion?
The Component Process Model (CPM) is Scherer’s major theory of emotions. It regards emotions as the synchronisation of many different cognitive and physiological components
How does Joseph LeDoux define Emotion?
Joseph LeDoux: Subjective Feelings
What is Mood?
Diffuse affect state, characterized by a
predominance of subjective feelings that affect the
experience and behavior of the person. May be long-
lasting, and not event focus
What is Affect Dispositions?
Affect Dispositions: Stable personality traits and
dispositions that have an affect core. The tendency of a
person to experience certain moods (anxious, jealous).
Can also describe psychopathologies
What are the 6 distinguishable emotions presented by Ekman?
Fear, Anger, Joy, Sadness, Disgust, and Surprise
Are their natural kinds of dimensions of emotions?
No studies have clearly identified a range of physiological
responses that represent specific emotional states
What are two dimensions to emotional experience?
Valence (good-bad) and Arousal (how
intense)
What is James-Lange theory of emotion?
Bodily changes come first and form the basis of an emotional experience. Thus, emotions are caused by bodily sensations (you become happier when you smile, you are afraid because you run)
What is Cannon-Bard theory of emotion?
According to the Cannon-Bard theory of emotion, we react to a stimulus and experience the associated emotion at the same time. The physical reactions are not dependent upon the emotional reaction, or vice versa.
What is Schachter-Singer’s two-factor theory?
Schachter and Singer’s (1962) Two-Factor Theory of Emotion suggests that physiological arousal determines the strength of the emotion, while cognitive appraisal identifies the emotion label. So, in this theory, the “two-factor” represents physiological change and cognitive appraisal change
What is the Limbic System?
The limbic system is the part of the brain involved in our behavioural and emotional responses, especially when it comes to behaviours we need for survival: feeding, reproduction and caring for our young, and fight or flight responses
How do objects and people acquire emotional significance?
Through threat conditioning. Experiment example: Rat hears sound -> no effect (before fear conditioning). Rat hears sound + recieves electric shock (after fear conditioning) -> once they hear the sound, even if they aren’t shocked, they freeze, increase in BP, HR, and respiration, and stress hormone release.
Describe threat conditioning in humans
Like other animals, the human amygdala is necessary
for the physical expression of a learned aversive response in fear conditioning
What are two techniques currently used clinically for Threat/Fear control?
Extinction and Cognitive Emotion Regulation
What is Extinction therapy?
Forms the basis for exposure therapy - Re-evaluate a stimulus associated with negative affect into neutral or
positive emotional terms
What is Cognitive Emotion Regulation?
Cognitive emotion regulation (CER) is described as the “conscious, mental strategies individuals use to cope with the intake of emotionally arousing information”
How does emotion aid attention and perception for emotional events?
The amygdala influences sensory brain regions to ease
processing of emotional events
How does emotion capture attention impairing attention to
non-emotional events
Parietal lobe regions that help us move attention
among aspects of an event are less active when an
emotional event is encountered
What is a flashbulb memory?
A flashbulb memory is a vivid, long-lasting memory about a surprising or shocking event that has happened in the past. 40% of memory details change after a year,
confidence in memory accuracy remains high
What is emotion’s influence on attention and perception?
Emotion’s influence on attention and perception allows for heightened awareness of stimuli in the environment that may pose a potential threat (Mike Davis & Paul Whalen, 1998) - weapon focus
Describe the Hierarchial model?
Location (goal), Trajectory (movement), and Muscles.
1) You think of your goal (conceptual level)
2) Many possible respond systems (parts of your body) and you must choose one
3) The motor system implements the chosen action plan by activating effectors (parts of your body that move)
Describe the Hierarchial model?
Location (goal), Trajectory (movement), and Muscles.
1) You think of your goal (conceptual level)
2) Many possible respond systems (parts of your body) and you must choose one
3) The motor system implements the chosen action plan by activating effectors (parts of your body that move)
Describe the Primary Motor Cortex and its Neurons
Voluntary actions require the primary motor cortex. Neurons code direction of movement and populations of neurons determine movement
What happens when there are lesions to area M1?
Hemiplegia: loss of voluntary movements on the contralateral side of body. Hyperactive reflexes (for maintaining posture). Reflexes are normally inhibited by cortex so that controlled action is possible
What happens when there is a lesion to area SMA (area 6)?
Alien hand syndrome: patient reaches out and grasps objects with affected arm, even when they try not to do so. Patients often aware it is their hand, but just can’t seem to control it. Problem with the goal/planning part of action.
What happens when there is a lesion to area SMA (area 6)?
Alien hand syndrome: patient reaches out and grasps objects with affected arm, even when they try not to do so. Patients often aware it is their hand, but just can’t seem to control it. Problem with the goal/planning part of action.
What are the two cortical regions for different motor areas?
1) Supplemental Motor Area (SMA), conceptual level, higher-order goals of action
2)Primary Motor Cortex (M1), motor implementation level, motor execution
What are the two cortical regions for different motor areas?
1) Supplemental Motor Area (SMA), conceptual level, higher-order goals of action
2)Primary Motor Cortex (M1), motor implementation level, motor execution
What cortical region is for internally-guided actions?
SMA: motor plans/goals for internally-guided actions. Example: Being asked to press lights in memorized sequence
What cortical region is for externally-guided actions?
PMC: motor plans for externally-guided actions. Example: Being asked to press lights as they flash
Why is the Basal Ganglia important for motor movements?
Facilitates the initiation and execution of voluntary movements
How do scientists think about emotion?
1) Basic emotions (as seen through facial expressions)
2) Dimensions of emotion (as reactions to events)
What does “some emotions are constructed” mean?
Some emotions are combinations of 2 or more basic emotions
What are the two theories of emotion?
Basic core emotions (according to Ekman) and an alternative Dimensional Approach
Explain the Dimensional Approach (theory of emotion) and give an example
Focuses on emotion as constructions that vary along continuous dimensions in response to events - all emotions are constructed in reaction to some stimulus in your environment
Give an example of dimensional approach
Example: the experience and expression of anger can be very different depending on who/what elicits it
What happened to threat/fear conditioning if there’s an Amygdala lesion?
There is impaired conditioned fear - lesions to amygdala do prevent learning of the conditioned startle response
Describe the Amygdala pathway
There’s an emotional stimulus which the sensory thalamus sends to the Lateral Nucleus of the Amygdala (LN), which then goes to multiple brain regions (sensory areas, medial temporal lobe, etc.), converges back to LN of Amygdala, and then the central nucleus (CN) of Amygdala
What do projections from LN to CN of Amygdala initiate?
Projections from LN to CN initiate will initiate an emotional
response (e.g., fight/flight) if a stimulus is determined to represent something threatening or dangerous
Damage to what disrupts fear conditioning
Damage to LN or CN severely disrupts fear conditioning
Why is Patient SP important?
Showed that amygdala appears to be necessary for fear conditioning in rats and humans
Describe Patient SP
Patient SP showed no increase in SCR (skin conductance response) to conditioned stimulus - impaired learning. However, explicit learning was intact -> she learned that blue square = shock
What pattern of results would you expect for someone with damage to the hippocampus but intact amygdala?
No explicit memory of the pairing (e.g., don’t remember seeing blue square). Intact implicit memory, showing a normal conditioned fear response (increased SCR) to the blue square. Thus, double dissociation!
What are the two pathways to the Amygdala?
Low road and High Road
Describe the low-road pathway
Sensory information goes directly from the thalamus to amygdala -> fast and crude analysis. Good for quick action upon detecting threat
1) Sensory areas
2) Thalamus (relay station)
3) Amygdala
Describe the high-road pathway?
Sensory information goes from thalamus to cortex for more elaborate processing, then routed to amygdala -> slow but more accurate analysis
What two frameworks support Schacter-Singer two-factor theory?
Misattribution of arousal and Excitation Transfer
Explain Misattribution of Arousal
Participants injected with epinephrine without their knowledge. Drug alone did not cause participants to report emotion - James Lange Theory would predict that the drug alone should cause emotion. The presence of a grumpy or happy person did. Drug made the reported emotions more intense (in either direction!)
What’s one unique way for Fear Conditioning in humans and elaborate
Social Learning. Humans don’t always need to directly experience negative events themselves to associate certain aspects of the environment with danger - we learn about germs and fear them without direct perception of
them. You can tell a person that a stimulus will be associated with pain, and that stimulus with activate the amygdala on its own - same thing happens when you see someone else get shocked after they see a specific cue
What is cognitive control?
Mental abilities that involve planning, controlling, and regulating the flow of information processing (Prefrontal cortex plays a crucial role)
What is Goal-Oriented behavior?
Interacting with the world in a purposeful manner; “goal-directed” is also used (Prefrontal cortex plays a crucial role)
Describe the effects of Frontal Lobotomies
Performed on psychiatric patients to alleviate symptoms. Patients become much calmer but there’s horrible side effects due to problems with cognitive control and goal-directed actions: lack of drive or initiative, without aim or purpose, etc.
What three types of memory rely on cognitive control?
Working memory, source memory, and recency memory
What’s the working memory task?
Keep in mind which slot the food is in. Requires the monkey to keep the location information online during the delay
What is the associative memory task?
Learn the relationship between a picture and food (no information is kept in mind over the delay) - monkey has to remember which cue image was associated with a reward
What is the associative memory task?
Learn the relationship between a picture and food (no information is kept in mind over the delay) - monkey has to remember which cue image was associated with a reward
What is source memory? And the evidence
Refers to recalling the source of learned information, such as knowledge of when or where something was learned. Evidence: dorsolateral prefrontal cortex damage patients have difficulty with source memory (increased false recognition)
What is Recency memory and why would this rely on cognitive control brain regions?
Remembering the order of events. It’s thought to rely on the ability to segregate and organize information
How do you test for Recency memory?
View a series of pictures over time, then judge which one was more recent - patients with frontal damage are worse at identifying which items were seen most recently
What is the Attentional Blink Paradigm and explain its correlation to the Amygdala
Words are presented quickly after another and are asked to pick up on designated words. People without Amygdala damage will likely pick up on these designated words. However, if the words are neutral…
