Lecture 14 - Perception and Memory Flashcards
Function of Left Hemisphere?
Controls reading and writing, calculation, and logical thinking.
Function of Right Hemisphere?
It controls three-dimensional sense, creativity, and artistic senses.
What are perceptual deficits?
- Apraxia
- Agnosia
- Unilateral neglect
- Complex Perceptual Deficits
Most, not all, perceptual deficits are associated with the BLANK hemisphere
Right
The integration and interpretation of sensation into meaningful information
Perception (Perception can affect any modality)
For deficit in BLANK, basic sensation needs to be intact.
Perception
Inability to recognize or make sense of incoming info despite intact sensory capabilities.
Agnosia
What area is damaged if you have agnosia?
(almost always, right hemisphere)
List the types of Agnosia
- Auditory
- Alexia
- Anosognosia
- Prosopagnosia
- Tactile Agnosia
“I hear the sound of a door bell and foot steps but I can’t recognize them.”
Auditory Agnosia
Lesion in Right PTO
Anosognosia, Prosopagnosia, Tactile Agnosia/Asterognosia, Visual Object Agnosia, (finger agnosia)
Lesion in Left PTO
Alexia (Usually left (language dominant) PTO area)
What does PTO stand for?
Parietal-temporal-occipital
“I can describe this object in my hand by touch, but can’t recognize what it is.”
Tactile Agnosia (Right PTO)
“I can see two animals (bear and bunny) and I can describe them but I can’t identify what they are.”
Visual Object Agnosia (Right PTO)
“I am unable to understand speech.”
Auditory Agnosia (left PTO - Wernicke’s)
“I am unable to comprehend written language.”
Alexia (left PTO)
Lack of awareness/denial of paralysis
Anosognosia (Right PTO)
“I can interpret emotional facial expressions and recognize other items in environment, but I can’t tell you who that person is.”
Prosopagnosia (Right PTO)
Tendency to behave as if one side of body/space does not exist
Unilateral Neglect (left-neglect, spatial neglect, hemispatial neglect)
Failure to respond to stimuli presented contralateral brain lesion
Unilateral Neglect (ex. drawings with left side missing). Most often, they don’t realize they’re missing anything
Most common lesion for Unilateral Neglect?
Right PTO
Occupational Deficits of Unilateral Neglect?
Makeup, ADLs, reading only left portion
What is often occurring together with Unilateral Neglect?
Visual field deficit
Ability to interpret info from visible light reaching the eye
Visual perception
Ability to perceive or react to size distance or depth aspects of environment
Spatial perception
What can be used to comprehend spatial relationships?
Schemas
What is an internal awareness of body and relationship to body and parts?
Body Schema
I can discriminate between my left and right sides of body/space.
RIght/Left discrimination
I have an impairment where I cannot identify fingers
Finger Agnosia
Examples of visuoperceptual abilities
Form discrimination and figure ground
“I can distinguish the difference from objects, such as m and n, a square or rectangle, the word house and horse.”
Form discrimination
Ability to differentiate foreground and background
Figure Ground
Examples of visuospatial abilities
Spatial relations, and topographical orientation
Relating objects to each other or self
Spatial relations
Topographical orientation
Determine location of objects and settings and route of location
What is impairment of capacity to perform purposeful movement in absence of paralysis?
Adult Onset Apraxia
Adult Onset Apraxia
Not due to any primary sensory/motor impairment or lack of comprehension, attention. Inability to perform particular purposive actions, as a result of brain damage
Where is damage most frequent for Adult Onset Apraxia?
Left hemisphere in the frontal lobe (premotor and SMA)
This interferes with ability to comprehend relationship of parts of whole, can’t draw and adage objects correctly
Constructional Apraxia
Only apraxia where lesion is on the right side?
Constructional Apraxia
“I have the inability to dress myself.”
Dressing Apraxia
Types of limb apraxia
Ideomotor, Ideational, conceptual
“Doctor asks patient to scratch his nose. He cannot. However, later on in the day, his nose is itchy so he scratches it.”
Ideomotor Apraxia (Carries out activity spontaneously, but difficulty executing a movement upon command)
“I have a candle and match but not sure how to light it. Which one goes first? Do I open the match and break it in half?”
Ideational apraxia (inability to create a plan for specific movement, incorrect sequencing )
“I am using a fork to brush my hair instead of using it to eat broccoli.”
Conceptual apraxia (difficulty using tools)
Perception stored that can be brought forward.
What is memory?
For something to become a memory, it must be…
Registered/encoded
Stored
Consolidated: transforming short term to long term. Retrieved: pull it up from some kind of cue
What exists across all sensory modalities or can be modality specific?
Memory
What are the different types of memory classification?
- Working
- Declarative (explicit)
- Procedural (implicit)
Maintain goal-relevant info for a short time
Working Memory
“I remember getting my first bike in fourth grade…” is an example of what kind of memory?
Declarative - Episodic (info specific to context, experiences, events)
“I know what a bike is. It has two wheels and a bell” is an example of what kind of memory?
Declarative - Semantic (facts independent of context)
“I haven’t ridden a bike in 15 years, but I know how it to ride it. You just hop on and go!” is an example of what kind of memory?
Procedural (Deals with skills learning, motor memory, habits)
What kind of memory depends on conscious reflection and cognitive processes and requires attention during recall?
Declarative
Semantic and Episodic are examples of what kind of memory?
Declarative
What are the 3 stages of memory?
- Immediate
- Short term
- Long term
This memory stage lasts 1-2 seconds, with examples including visual memory, auditory memory, etc
Immediate memory
This memory stage is brief storage of stimuli that has been registered and perceived
Short term memory
Loss usually occurs after a few mins unless material is continuously rehearsed
Short term memory
Here are 5 words to remember and recall. What memory stage are you using?
Short term memory
Relatively permanent storage of info processed in short term memory
Long term memory
Chunking is gathering info to make it easier to remember. This is a strategy for what type of memory stage?
Short term memory
Memory stage where you consolidate
Long term memory (conversion of STM to LTM)
This memory stage has a large capacity
Long term memory
What is the difference between sight & visual perception?
- Sight: transduction of light into electrical signals, sent to V1
- Visual perception: the integration of visual impressions into psychologically meaningful information
What are Dr. P’s main perceptual problems? Name each and give examples from the story (wife hat story)
- Prosopagnosia
- Visual object agnosia
- Anosognosia
- CHH (due to info at end of story re: optic tumor AND the fact that he could re-orient to retrieve that information
What parts of Dr. P’s brain are most likely affected? (wife hat story)
PTO areas
- Discuss how each of the perceptual problems effect Dr. P’s everyday functioning. Give examples from the story.
don’t know answer yet!
How did Dr. P’s deficits affect his other senses?
His perceptual impairments made those other senses even more important to him (tactile, visual acuity, auditory, etc). He attended to these other senses much more than someone who does not have brain damage.
On p. 10 Sacks says that he “scratched the sole of his foot with a key…”. What was he testing for?
Babinski reflex
What is your reaction to the following quote: “…Dr. P was not fighting, did not know what was lost, did not indeed know that anything was lost. But who was more tragic, or who was more damned – the man who knew it, or the man who did not?” (p. 16).
don’t know yet
What type of memory deficit did Jimmie have in The Lost Mariner?
Retrograde and Anterograde
Did he have a deficit in procedural or declarative memory? Why? Give examples from the story.
Declarative
What neuroanatomical structures are associated with declarative types of memory?
Cortex and HC
What specific structure is associated with Jimmie’s memory loss? Where is this located?
Mammillary bodies of the hypothalamus
Loss of declarative memory and long term semantic and episodic
Amnesia
“I can’t remember everything/anything that happened before the accident.”
Retrograde Amnesia (Loss of memory of events before the precipitating trauma)
“I don’t remember what I did today. I’ve lost memory of events occurring after the injury.”
Anterograde
What is Korsakov’s syndrome?
A disorder caused by deficiency in thiamine (vitamin B1) causing damage to medial thalamus and mammillary bodies of hypothalamus. It is seen in chronic alcoholism and severe malnutrition. Symptoms include anterograde amnesia (inability to create new memories) and confabulation (creation of false memory, adding new details)
Disorder caused by deficiency in thiamine
Korsakov’s syndrome (Jimmy from Lost Mariner story had this)
This syndrome is seen in alcoholism and severe malnutrition
Korsakov’s syndrome
Where is the damage in the brain for Korsakov’s syndrome?
Medial thalamus and mammillary bodies of hypothalamus
Age related, progressive, and irreversible brain disorder
Alzheimer’s Disease
This is the most common type of dementia
Alzheimer’s
When do Alzheimer symptoms occur?
Usually after 65 with risk increasing with age. NOT NORMAL PART OF AGING (more genetic) and can be late or early onset
Diagnosis of Alzheimer?
No specific test to confirm AD diagnosis, and analyze symptoms to determine diagnosis of disease
Course of Alzheimer’s… Starts with signs of forgetfulness then…
inability to recall words
failure to produce/comprehend language
get lost easily
neglect to dress, groom, feed
What is a reason for a person with Alzheimer’s to wander and become lost?
Motion blindess: inability to interpret flow of visual info
Person has uncontrollable emotional outbursts
Alzheimer’s
What is going on at the level of the brain for someone with Alzheimer’s?
- Neurofibrillary tangles. In normal neuron, tau (protein) forms part of microtubule support system. In Alzheimer’s, tau is abnormal and twists into tangles, leading to loss of transport system (neurons can’t function typically)
- Neuritic (Beta-Amyloid) plaques: Extracellular deposits of amyloid builds up between neurons. In healthy brain, it is broken down and eliminated. In person with AZD’s brain, fragments accumulate, forming hard insoluble plaques and interfere with communication
What are neuritic plaques?
Extracellullar deposits of amyloids build up between neurons, form insoluble plaque that interfer with communication. Trigger immune response. (AZD)
What are Neurofibrillary tangles?
(AZD), neuron’s tau (protein) is abnormal and twists into tangle leading to lose of transport system
What are the structural changes of the brain with someone with AZD?
Cortical atrophy shrinkage, degeneration of cerebral cortex, amygdala, hippocampus, enlarged ventricles (all lead to loss of connections between neurons responsible for learning and memory)
