Post Midterm #2 Flashcards
Implicit memory
Unconscious memory (implicit memory, nondeclarative memory)
Just “happens” (don’t know when you learn this
“show me”
Memories that influence behavior in an automatic, involuntary manner
Relates to automatic adjustments to perceptual, cognitive, and motor systems that occur beneath the level of conscious awareness
- procedural memories (how to ride a bike)
- perceptual memories (how to tell identical twins apart, unconsciously)
- stimulus-response memories (salivating in response to a tone)
Explicit memory
Consciously accessible memory (explicit memory, declarative memory)
Memories of events and facts that we can think and talk about.
“tell me”
What are the two types of episodic memories?
Episodic and Semantic memory
What is Episodic memory
Personal experiences associated with a time and place. Autobiographical memory that involves contextual information and is learned all at once.
What is SemaNtic memory
Encyclopedic memory of facts and general information, often acquired gradually over time. This knowledge need not be associated with the time or place in which we learned the information.
Describe Motor learning [HINT] (procedural learning) – implicit memory
Learning to make skilled, choreographed movements. Procedural learning
The basis of motor skills (bike riding, ball throwing, etc.…)
Involves different brain areas involved in movement
Motor learning involves learning how to make a sequence of coordinated movements
*Between-session learning, where improvements in motor behavior are seen following a period of memory consolidation
What parts of the brain are involved in motor learning?
The cerebellum, thalamus, basal ganglia, and motor cortex are all involved in motor learning
What is Perceptual learning – implicit memory
Learning to recognize stimuli as distinct entities.
The basis of recognition & categorization
Perceptual learning enables us to recognize and identify object or situations.
It is a pattern recognition system. (allows you to recognize when things change)
Through perceptual learning we recognize changes / variations in familiar stimuli and respond to those changes.
See picture – if something in that picture changes, this allows you to notice what changed
What parts of the brain are involved in perceptual learning?
Largely dependent on the neocortex – sensory association areas
This unconscious, implicit learning involves changes in the strength of connections between neurons in primary and association sensory cortices
What is Relational learning (stimulus-stimulus learning) – explicit memory? What parts of the brain is involved with this?
Learning relationships among individual stimuli. Stimulus-Stimulus learning
The basis of declarative memory (episodic and semantic)
Largely dependent on the hippocampus and neocortex
What is Stimulus–response learning – implicit and explicit memory? What parts of the brain are involved with this?
Learning to perform a particular behavior when a particular stimulus is present. Includes classical and instrumental conditioning.
The basis of classical (Pavlovian) and instrumental (operant) conditioning
Involves different brain areas depending on the stimulus and response
Unconditioned stimulus vs. conditioned stimulus?
Unconditioned stimulus
a stimulus that has inherent value, like food or a painful shock.
Conditioned Stimulus
a stimulus that was initially perceived as neutral (e.g., a tone) but now is perceived as predictive of an US.
Unconditioned Response vs. Conditioned Response
Unconditioned response
a behavioral response that is largely innate, hard-wired (unlearned, unconditioned).
Conditioned Response
a behavioral response that occurs in response to a CS. The behavior is often similar to the UR that was elicited by the US during training.
What is sensory memory?
Perceptual memory; lasts only a couple of seconds or less
Allows an individual to retain the experience of the sensation slightly longer than the original stimulus. Occurs in each of the senses.
Example; people often reflexively say “what?” when they hear something while distracted, but then they quickly realize they did hear what was said.
What is short-term memory?
Lasts for seconds to minutes
Small fraction of sensory information enters short-term memory.
The memory capacity of short-term memory is limited to a few items, such as the digits in a phone number or the letters in a name.
The length of short-term memory can be extended through rehearsal. For example, you might be able to keep a phone number in short-term memory by repeating it to yourself.
What is long-term memory?
Persists after getting distracted and after a nap
Select information from short-term memory is consolidated into long-term memory.
Long-term memories can be retrieved throughout a lifetime and are strengthened with every retrieval event
What is implied motion?
Movement is processed through the dorsal stream (in parietal cortex)
There is more stimulus in the dorsal stream when looking at a picture of someone doing an action (i.e.) hitting a baseball
What does visual agnosia have to do with memory?
Damage to regions of the brain involved in visual perception not only impair ability to recognize visual stimuli but also disrupt people’s memory of visual properties of familiar stimuli
What is Instrumental conditioning (aka Operant conditioning aka Reinforcement learning) ?
Learning from the consequences of your actions, from the receipt of reinforcement or punishment. The likelihood of you repeating an action depends on whether it was previously reinforced or punished.
In contrast to Classical (Pavlovian) learning, operant conditioning requires that the animal can move and make decisions that influence their environment (i.e., decisions that have consequences).
What is Reinforcing Stimulus
Appetitive stimulus. When it follows a particular behavior, it increases the likelihood the animal will repeat the behavior. Reinforcement makes the behavior more likely to occur.
What is a Punishing stimulus?
Aversive stimulus. When it follows a particular behavior, it decreases the likelihood the animal will repeat the behavior. Punishment makes the behavior less likely to occur
What type of instrumental learning happens beneath level of consciousness?
Particularly relevant in drug addiction
Take it in an environment
Brain likes it
Next time when you are in that situation you are more likely to do it again
More you take the drug – the more the brain says YES
Example of our conscious control not being in full charge
Unconscious part of the brain takes charge
What are the two main pathways between sensory and motor cortices
Direct transcortical connections
The basal ganglia
What is the pathway of direct transcortical connections between the sensory and motor cortices?
Connections from one area of the cerebral cortex to another
Involved in the creation of new complex motor sequences that involve deliberation or instruction
What is the pathway of the basal ganglia? It is between the sensory and motor cortices
Collection of nuclei in the forebrain that regulate habit learning.
It integrates sensory and motor information from throughout the brain, initially acting as a passive “observer”
When successful behaviors are repeated over and over, the basal ganglia starts to automate the stimulus-response process.
The basal ganglia creates habitual ways of responding, leaving transcortical circuits free to do something else.
When this happens, habitual movements can be effective without any conscious consideration of the details.
What is Dopamine signaling?
Drives habit learning by controlling synaptic plasticity in the basal ganglia.
It provides a “thumbs up / thumbs down” signal that determines the likelihood an animal will repeat a behavior
Where do most areas of the cerebral cortex project to?
Nearly every area of the cerebral cortex projects to the basal ganglia.
Where do inputs to the basal ganglia primarily synapse?
Inputs to the basal ganglia primarily synapse in an area called the striatum, which consists of three parts: the caudate, putamen, and nucleus accumbens.
How do dopamine neurons in the midbrain (substantia nigra and ventral tegmental area) signal reinforcement and punishment?
by releasing more or less dopamine in the striatum (caudate, putamen, nucleus accumbens).
True of False: The overall amount of dopamine in the striatum seems to reflect the animal’s motivational state and the value of moving in and engaging with the environment
TRUE
Transient fluctuations in dopamine signaling seem to drive learning by signaling how unexpectedly good or bad the current moment is
What does the striatum do?
Different areas of the striatum process information from different cortical areas.
For example, the nucleus accumbens in the ventral striatum receives input from limbic areas such as the hippocampus, amygdala, and parts of PFC
Seems to regulate people’s priorities and cravings.
What happens to learning when lesions of the basal ganglia occurs?
Disrupt reinforcement learning and habit learning, but they do not strongly affect perceptual learning or stimulus-stimulus learning.
Who is Henry Gustav Molaison (HM)?
Doctors cut out his hippocampus bilaterally to cure his epilepsy
It worked, but he lost the ability to form new explicit memories (severe anterograde amnesia).
He also suffered from a graded retrograde amnesia (events that occurred within 1 or 2 years were lost as well as some events that happened even longer ago than that).
He still had a brief working memory and a high IQ, but he could not learn new words or names or learn to navigate a new space.
What is Korsakoff’s syndrome?
Permanent anterograde amnesia caused by brain damage, usually resulting from chronic alcoholism. Korsakoff’s patients are unable to form new memories but can still remember old ones before the brain damage occurred.
What is Confabulation?
Reporting of memories of events that did not take place without intention to deceive
Seen in people with Korsakoff’s syndrome
What is memory consolidation?
Most psychologists believe that learning consists of at least two stages: short-term memory and long-term memory
Simplest model of the memory process
The hippocampus is not the location of either short or long-term memories, but it is critical for the consolidation of short-term memories into explicit long-term memories
What is Anterograde amnesia?
inability to learn new information
or retain new information ‘after’ brain injury. Memory for events that
occurred before the injury remain largely intact
What is retrograde amnesia
inability to remember events that
occurred ‘before‘ the brain injury.
What is amnesia
A deficit in memory caused by brain damage or brain diseases (it can also be temporarily caused by different drugs).
Complete amnesia in either direction is rare
What is Anterograde amnesia
Refers to the inability to form new explicit memories ‘after’ brain injury. Memory for events before the injury remain largely intact.
what is retrograde amnesia
Refers to the inability to remember events that occurred ‘before‘ the brain injury.
Commonly seen in neurodegenerative diseases that are associated with brain-wide neurodegeneration and that also affect one’s ability to think, learn, and make decisions.
What is relational learning?
Damage to the hippocampus or to regions of the brain that supply its inputs and receive its outputs causes anterograde amnesia, but nondeclarative learning ability remains intact.
What are spared learning abilities
When amnesic patients are trained and tested, we find that they are capable of three of the four major types of learning: perceptual learning, motor learning, and stimulus–response learning.
However, amnesic patients do not explicitly remember anything about what they have learned.
What is lateralization? Which part of the brain is responsible for language?
Verbal behavior is lateralized in the brain.
Most language disturbances occur after damage to left side of brain, regardless if people are left-handed or right-handed
The left hemisphere is dominant for speech in 90 percent of the population
Right-hemisphere speech dominance is seen in 4 percent of right-handed people and 27 percent of left-handed people
At around what age can people recognize the voices of particular individuals?
Even newborn infants can recognize the voices of their parents.
Can people with left hemisphere damage recognize voices even if they might not be able to understand words?
YES. People with left hemisphere damage might not be able to understand words but they could still recognize voices.
Phonagnosia
A disorder where people have great difficulty recognizing voices.
It results from localized brain damage to the right superior temporal cortex
What is aphasia
Refers to a disturbance in understanding, repeating, or producing meaningful speech.
The difficulty must not be caused by simple sensory or motor deficits or by lack of motivation.
You can see, hear, move but you can’t speak
Damage to sensory association cortex causes deficits in understanding language. The aphasia may be described as a: (multiple answers)
posterior aphasia
sensory aphasia
receptive aphasia
Wernicke’s aphasia
fluent aphasia
Damage to the frontal lobe causes deficits in speaking. The aphasia may be described as a: (multiple answers)
anterior aphasia
motor aphasia
expressive aphasia
Broca’s aphasia
non-fluent aphasia
What happens if one gets a stroke in the “Language comprehension ‘posterior language area’”?
you cannot understand language/don’t use it intelligently
They can read but they can’t understand what they are reading
They can point at something that they want but they cannot TELL you what it is.
What is the Posterior Language Area
Located at the junction of the temporal, occipital, and parietal lobes, around the posterior end of the lateral fissure.
It is critical for language comprehension (regardless of whether the words are heard, seen, or spoken).
Damage to the posterior language area causes…
Transcortical Sensory Aphasia
what is Transcortical Sensory Aphasia
Speak fluently but words have no meaning to you
Failure to comprehend the meaning of words and an inability to express thoughts with meaningful speech.
Word perception and speaking might be fine (without any comprehension of what is heard or spoken).
For example:
Word repetition (e.g., repeat after me…)
Reading (without understanding)
Writing (without understanding)
What is conduction aphasia
Characterized by an inability to repeat the exact words you hear. Other than that, you are fine, that is you have meaningful, fluid speech and good speech comprehension.
When asked to repeat the word ‘house’, the person may say “home”.
When asked to repeat a nonsense word like ‘blaynge’, the person will be unable to do it. They will just say I didn’t hear you.
connection between Wernicke’s area and Broca’s area
arcuate fasciculus
Where and what is the Wernicke’s area
Involved in analysis of speech sounds and in recognition of spoken words.
Region of auditory association cortex on left temporal lobe of humans.
What is Pure word deafness
result of damage to a small part of Wernicke’s area
Pure word deafness is a disorder of auditory word recognition, an inability to comprehend or repeat spoken words.
“I can hear you, but I don’t recognize the words you are saying. I even have trouble repeating what you say.”
What is the Wernicke’s Aphasia
the result of damage to both Wernicke’s area and the Posterior language area, which means you have features of transcortical sensory aphasia and pure word deafness.
poor language comprehension
These people can have fluent speech production, but what they say is meaningless and typically filled with function words, such as a, the, in, about (as opposed to content words that convey meaning, such as nouns, verbs, and adjectives).
Transcortical sensory aphasia
Patients with transcortical sensory aphasia have trouble with language comprehension, but they can repeat what other people say to them; they can recognize spoken words.
Wernicke’s aphasia
Patients with Wernicke’s aphasia have trouble with language comprehension and are generally not capable of repeating what other people say to them.
What would a brain scan of Transcortical sensory aphasia and Wernicke’s aphasia look like?
Both of these aphasias are associated with damage in and around Wernicke’s area, including Posterior Language Area.
These brain areas aren’t really separable, or rather the functions of language comprehension and spoken word recognition are interweaved in and around Wernicke’s area.
You wouldn’t be able to differentiate between Wernicke’s aphasia and transcortical sensory aphasia just by looking at a brain scan
What does damage to the visual word form area (VWFA) do?
Disrupts the ability to perceive written words
People with this damage (Pure Alexia or Pure Word Blindness) cannot read, as they cannot recognize written words. However, they can write just fine. They just can’t read what they write.
What does damage to Broca’s area in the (left) inferior frontal lobe do?
makes it difficult for patients to express themselves verbally
Hard time talking and writing: they recognize it and become frustrated
Comprehension is fine and their hands and mouths work but they can’t communicate (hear their mouth saying something different than what they want to say)
What are three of the semi-distinct issues in Broca’s Aphasia
Articulation problems, Agrammatism and anomia
What are articulation problems?
Movement of tongue, lips, jaw, and other speech organs to make speech sounds. Articulation problems might make it hard for someone to hear the words you are saying. Or it could cause a sequencing problem: lipstick saying likstip.
What is agrammatism
Difficulty comprehending or using grammatical devices, such as verb endings (-ed) and word order (e.g., man bit dog).
People with agrammatism typically do not derive meaning from the sequence of words or the grammar of sentences. Thus, they almost exclusively use content words (nouns, adjectives, verbs, etc.) without any function words (the, on, about, etc.)
What is anomia
Difficulty in finding (remembering) the appropriate word to describe object, action, or attribute; one of symptoms of Broca’s aphasia
What is Anomic Aphasia
People with anomic aphasia have a hard time thinking of the word they want to say. They can understand what other people say just fine. If their speech is fluent, they will often describe things in roundabout ways (circumlocution)
what is Circumlocution
Strategy by which people with anomia find alternative ways to say something when they are unable to think of most appropriate word
Byron is a Wernicke’s aphasia patient. According to his wife, what can and can’t he do?
He understands over half of what he hears, and he can understand what he reads in a book or newspaper.
Byron cannot spell or repeat words.
He can read numbers, do math problems, make change, and analyze a financial statement better than I can.
So, from 0% comprehension and “word salad” to 60% comprehension and some functional language is not bad in 5 years.
What is the likelihood of having a stroke related to?
Related to age – probability doubles each decade after 45 years of age and reaches 1–2 percent per year by age 75
What is Atherosclerosis
Process in which linings of arteries develop a layer of plaque, deposits of cholesterol, fats, calcium, and cellular waste products.
Risk factors include high blood pressure, cigarette smoking, diabetes, and high blood levels of cholesterol.
Precursor to heart attacks (myocardial infarction) and strokes
What is a hemorrhagic stroke
rupture of cerebral blood vessel
what is an ischemic stroke?
occlusion of a blood vessel
87% of strokes are ischemic
What is a thrombus
Blood clot that forms within a blood vessel, which may block it and reduce blood flow to the affected area.
what is an embolus
Piece of matter (such as a blood clot, fat, or bacterial debris) that dislodges from its site of origin and occludes an artery. In the brain, an embolus can lead to a stroke
What is an example of an approach to minimize amount of brain damage caused by strokes?
Administer drugs that dissolve blood clots in an attempt to reestablish circulation to an ischemic brain region
This approach has met with some success. For example, administration of a clot-dissolving drug called tPA (tissue plasminogen activator) after the onset of a stroke has clear benefits, but only if it is given within 3-4 hours.
What is an approach to minimize amount of brain damage caused by strokes with a device?
Devices can be deployed through the vascular system to the site of an occlusion. The devices use various strategies to secure and/or remove occlusions. The devices can include coils (a), aspiration devices (b), or be incorporated into stents (c).
After Stroke Treatments
Drugs that reduce swelling and inflammation
Physical, speech, and/or occupational therapy
Exercise and sensory stimulation (constraint-induced movement therapy)
What is a tumor
mass of cells whose growth is uncontrolled and that serves no useful function
What is a non-malignant tumor
Noncancerous, “benign” tumor.
Has distinct border and cannot metastasize
what is a malignant tumor
Cancerous (literally, “harm-producing”) tumor.
Lacks distinct border and may metastasize
what is a metastasis?
Process by which cells break off of a tumor, travel through the vascular system, and grow elsewhere in the body
What is the difference between a malignant and non-malignant tumor
Malignant
If the tumor is cancerous it grows by infiltrating the surrounding tissue, and there will be no clear-cut border between tumor and normal tissue
Non-Malignant
If there is a border (encapsulate), the tumor is non-malignant; the surgeon can cut it out, and it will not regrow
What happens when surgeons remove malignant tumore and miss some cancer cells?
These cells will produce new tumors
Any tumor growing in the brain, malignant or benign, can produce neurological symptoms and threaten the patient’s life. Tumors damage brain tissue by two means
compression and infiltration.
What can a compression tumor do?
Can directly destroy brain tissue, or it can do so indirectly by blocking flow of cerebrospinal fluid and causing hydrocephalus
What is an example of a malignant tumor
Glioma
What is a Glioma
The tumor initiating cells originate from the neural stem cells that make glia.
They rapidly proliferate and are more resistant to chemotherapy and radiation than most tumor cells.
The survival rate from malignant gliomas is very low
What is an example of a non-malignant tumor
Meningioma
What is a Meningiomatumor
Encapsulated tumor
It is composed of cells that constitute the meninges – the dura mater or arachnoid membrane – often right between the two cerebral hemispheres.
Tumor of the cells of the meninges
May be encapsulated but it is still very damaging.
It can (i.e.) displaced the right side of the brain. The right ventricle is almost completely occluded.
What are disorders caused by infectious diseases?
Encephalitis
Meningitis
Polio
Rabies
Herpes simplex virus
What is Encephalitis
Inflammation of the brain caused by infection (bacterial or viral), toxic chemicals, or allergic reaction
The first symptoms are headache, fever, and nausea
What is meningitis
Inflammation of meninges caused by viruses or bacteria
The first symptoms are headache and stiff neck
What is Polio (acute anterior poliomyelitis)
Viral disease that destroys motor neurons of the brain and spinal cord
Paralyzed if it gets to the brain
What is Rabies
Fatal viral disease that causes brain damage; usually transmitted through the bite of an infected animal
What is herpes simplex virus
Virus that normally causes cold sores near the lips or genitals. In rare cases, it instead enters the brain causing encephalitis and brain damage
Rarely but possible to get to the brain
What is a closed head injury
Caused by a blow to the head with a blunt object
The brain comes into violent contact with the inside of the skull (coup)
The brain then recoils in the opposite direction and smashes against the skull again (contrecoup)
What is an open head injury
Penetrating brain injuries (also called open head injuries) obviously cause damage to the portion of the brain that is damaged by the object or the bone
In addition, damage to blood vessels can deprive parts of the brain of their normal blood supply
Accumulation of blood within the brain can cause further damage by exerting pressure within the brain
what is a traumatic brain injury
A serious health problem
Almost a third of deaths caused by injury involve TBI.
In survivors, scarring often forms within the brain, around the sites of injury, which increases risk of developing seizures.
Many people receive brain injuries but are not diagnosed.
Even mild cases of TBI (mTBI) greatly increase a person’s risk of developing brain problems down the road.
For example, the likelihood of Alzheimer’s disease is much higher in a person who has received blows to the head earlier in life
What is seizure disorder
Preferred term for epilepsy
Sometimes, if neurons that make up motor system are involved, a seizure can cause a convulsion, which is wild, uncontrollable activity of the muscles But not all seizures cause convulsions; in fact, most do not
what are convulsions
Violent sequence of uncontrollable muscular movements caused by seizure
What are causes of seizures
The most common cause is scarring, which may relate to an injury, a stroke, the irritating effect of a growing tumor, or a developmental abnormality in the brain
Other causes are high fevers (especially in young children) and withdrawal from GABA agonists, such as alcohol and barbiturates.
Many cases are idiopathic (of unknown causes).
Neural network instability and increased risk of seizures can come about for genetic reasons, involving gene mutations that affect what?
The amount or function of different ion channels in the brain
The reciprocal wiring of excitatory and inhibitory neurons
The rules that govern synaptic plasticity
What is a Partial (focal) seizure
Seizure that begins at a focus and remains localized, not generalizing to rest of brain
What is a simple partial seizure
Seizure that does not produce loss of consciousness.
What is a complex partial seizure?
Seizure that produces a loss of consciousness.
What is a generalized seizure
Seizure that involves most of the brain (nonlocalized seizure).
Includes tonic-clonic seizures, atonic seizures, and absence seizures
True or false: Every time a seizure occurs, they get worse than the time before
TRUE
What is an aura
Sensation that precedes a seizure. Its exact nature depends on the location of the seizure focus
What is a tonic-clonic seizure
A generalized, grand mal seizure that typically starts with an aura that is followed by a tonic phase and then a clonic phase. This type of seizure involves convulsions.
Usually aware when it is happening – tingling in hand, blackout vision…
What is a tonic phase
First phase of tonic-clonic seizure, in which all of patient’s skeletal muscles are contracted
What is a clonic phase
Second phase of a tonic-clonic seizure, in which patient shows rhythmic jerking movements
Fetal alcohol syndrome
Babies born to alcoholic women are typically smaller than average and develop more slowly.
A particularly serious condition associated with alcohol consumption during the 3rd and 4th week of pregnancy is fetal alcohol syndrome, which is associated with certain facial anomalies and severe intellectual disabilities
What causes Inherited Metabolic Disorders ?
Several inherited “errors of metabolism” can cause brain damage or impair brain development
what are “errors of metabolism”?
Genetic abnormalities in which recipe for a particular protein is in error.
Typically, the cause is that an enzyme is not synthesized on account of mutations in both copies of the gene. (both = mom and dad)
If the enzyme is a critical one, results can be very serious
what is Phenylketonuria (PKU)
Hereditary disorder caused by the absence of enzyme that converts the amino acid phenylalanine to tyrosine
Accumulation of phenylalanine causes brain damage unless a special diet is implemented soon after birth
what is Tay-Sachs disease?
Heritable, fatal, metabolic storage disorder
Lack of enzymes in lysosomes causes accumulation of waste produces and swelling of cells of brain
what is Down Syndrome caused by?
Caused not by inheritance of a faulty gene but by possession of extra twenty-first chromosome.