cognition, motivation and mood Flashcards
Cognition refers to
processes involved in gaining knowledge, comprehension, and completing tasks
it includes:
- memory
- languauge
- oreintation
- judgement
- performing actions (praxis)
- problem solving
6 neurocognitive domains
1.** excectuive function**- planning, decision making, working memory, responding to feedback, inhibiition, flexibility
2. complex attention- divided attention, selective attention, processing speed, sustained attention
3. social cognition- insight, thoery of mind, recognition of emotions
**4. learning and memory **- free recall, cued recall, recognition memory, semantic and autobiographcal long term memory, implicit learning
5. language- object naming, ,word finding, grammar and syntax, recpetive languagem fluency
6. perceptual-motor function= visual perception, visuocontrcutional reasoning, perceptual-motor coordination
encoding of information and experiences into neural pathways for later retrieval (encoding in neural pathways so you can remember later)
provides a basis of shared knowledge, like language and social concepts
Memory
3 types of memory
-
Working memory- something that is happening at the time you are using
2.Declarative memory- FACTS you know - Procedural memory- how to do something (riding a bike)
- Temporary storage and manipulation of information
- Maintains goal-relevant information for short time
- Essential for holding a conversation, problem solving, mental navigation, reasoning
- Requires the lateral pre-frontal cortex, temporoparietal association cortex, and white matter tracts (myelinated axons communicate b/w areas) connecting the two areas
- Will not remember for years (days, weeks, months)
Working Memory
- Recollections that can be easily declared (e.g., answering trivia questions)
- Requires attention to recall, so aka conscious or explicit memory
- 3 stages:
- Encoding
- Consolidation
- Retrieval
- Ex: Answering trivia question
- when you first learn it, it gets encoded and then consolidated and then you are retrieving info when answering it
Declarative Memory
what is the first step of declarative memory?
- Enhanced by paying attention to different parts of information, emotional arousal, linking new information to other information, reviewing.
- Distraction or lack of interest interferes with encoding.
- If other senses are involved- helps with encoding- use smell or sound to help remember
Encoding
what is the 2nd step of declarative memory?
- Stabilization of memory networks for long-term
- Involves building new synapses and strengthening them; connecting neurons together into circuits that when activated will allow you to recall information
- Requires anatomical and functional changes in brain called long-term potentiation (LTP) (glutamate recptors) and reorganization of neural circuits in medial temporal lobe
Consolidation
* Memory Hub
* Site of extensive integration of information
* Bits of information (action potentials) about an “event” or an “object” that converge simultaneously in a subset of neurons lead to anatomical strengthening of connections between those neurons (Long-Term Potentiation; LEARNING)
* When memories converge- connections, this is how the brain consolidates them
* In future, when only one or a few of those neurons fire, they reciprocally activate all neurons in the circuit and the event or object is recalled, together with all the associated emotions (MEMORY)
Hippocampus
describe 2 types of ionotropic receptors in hippocampus
1.** AMPA-** normal sodium channels - Na causes AP to fire
2.** magnesium blocks NMDA recoptor-** ca binds and removes mg from channel so sodium and ca can enter cell= important for long term potentiation
**cingulate cortex **is important for _________ memory and emotional salience of memories
spatial
Frontal cortex is important for ________________ memory (recall of objects, facts and events)
declarative
which lobe is responsible for declarative memory and consolidation?
medial temporal lobe
____________ ______________is when you can’t recall memories from your past
retrograde amnesia
when you can’t form new memories but can still remember things from before you developed this amnesia
aterograde amnesia
Subjective cognitive impairment (SCI)
- subjective decline in memory and functioning (patient reported- cannot remember things as well as they used to)
- does not meet the clinical definition of MCI in which subtle changes may become visible to observers and cognitive impairment is elicited with testing
Mild cognitive impairment
- syndrome of cognitive decline that exceeds normal age-associated changes, but is less than that seen in dementia.
- When you give battery of cognitive tests, do not do as well as they should for age and cog level
What is dementia?
- A syndrome due to disease of the brain, usually of a chronic or progressive nature.
- disturbance of multiple higher cortical functions, including memory, thinking, orientation, comprehension, calculation, learning capacity, language, and judgement.
dementia risk factors
60-70 years
female
-prior stroke
- heart ds
- diabetes
- diet
- cholesterol problems
3 Lab tests for dementia
- blood tests
- Electrical/Imaging
- CNS samples
Neuro-psychiatric symptoms in dementia
- Changes in personality
- Delusions and hallucinations
- Mood
- Catastrophic reaction
- Sundowning (pretty clear in the day, in the evening- they get more confused and get worse symptoms): drowsiness, confusion, ataxia, falls.
Symptoms of ……
* Wandering
* Change in eating habits
* Altered sleep
* Incontinence
dementia
Dementia in Huntington’s disease
- **more motor abnormalities and fewer language abnormalities **than in the cortical type of dementia
- psychomotor slowing and difficulty with complex tasks, but memory, language, and insight remain relatively intact in the early and middle stages of the illness
- features distinguishing from Alzheimer’s are the high incidence of depression and psychosis, in addition to the classic movement disorder
- As the disease progresses, the dementia becomes complete and distinguishing factors become less clear
Dementia in human immunodeficiency virus [HIV] disease
((AIDS) dementia complex, or HIV dementia)
require laboratory evidence for systemic HIV, at least two cognitive deficits, and the presence of motor abnormalities or personality changes
Dementia in Parkinson’s disease
- Dementia is present in about 35% - 55% of patients with Parkinson’s disease.
- **Dementia occurs usually late in the disease
- Lewy bodies may accompany the neuronal loss in involved nuclei.**
- Cognitive symptoms in PD usually appear after physical symptoms.
Lewy body dementia
- Visual hallucinations and cognitive fluctuations common
- abnormal protein deposits called Lewy bodies that accumulate in the brain
Normal pressure hydrocephalus Triad
- Dementia: typically subcortical
- Gait instability
- Urinary incontinence
Normal pressure hydrocephalus
- Walk with “feet stuck to floor”- can’t conduct motor movement as well
- Symptoms progress over weeks to months
- CT shows ventricular enlargement out of proportion to cortical atrophy
- Treatment- lumbar puncture
NTM: seratonin (general arousal)
origin: raphe nuceli
NTM: Norepi (attention- directs concoiusness)
origin: locus coeruleus and medial reticular zone
NTM: Acetycholine (selective attention based on goals)
origin: PPN (pedunculoponteine nucleus)
NTM: dopamine (motivation, motor activity and cognition)
origin: VTA (ventral tegmental area)
and substantia nigra
RAS (reticular activating system)
axons ascend from** basal forebrain- thalamus–cerebral cortex (go to cerebral areas involved in conscousness to control sleep/wake cycles and directing attention when awake)
**
stimulated by orexin in hypothalamus in response to light from eye
Turn on or off intracellular signaling cascades that regulate ion channels, gene expression
Reticular Formation
4 nuclei of Reticular Formation
- Pedunculopontine Nucleus
- Raphe Nuclei
- Locus Coeruleus & Medial Reticular Area
- Ventral Tegmental Area (VTA)
- Nucleus of caudal midbrain
- Utilizes Ach, GABA, Glu
- Projects to frontal cerebral cortex, basal forebrain, intralaminar regions of thalamus, brainstem, cerebellum, reticulospinal tract
* Important for modulation of basal ganglia for goal-directed movements
Pedunculopontine Nucleus
* Serotonergic nuclei (serotonin)
* Innervate thalamus, tectum, striatum- basal ganglia, amygdala, hippocampus, cerebellum, cerebral cortex, spinal cord
* Important in pain regulation, mood regulation, sleep/wake cycle, and attention
Raphe Nuclei
locus coeruleus and medial reticular zone nuclei
- nonadrenergic nuclei /norepi
- same targets as raphe: thalamus, tectum, striatum- basal ganglia, amygdala, hippocampus, cerebellum, cerebral cortex, spinal cord
- waking, arousal in repsponse to orexin
VTA- ventral tegmental area
**- dopaminergic midbrain region **
- innervates brain regions involved in **motivation and decision making **
- cocaine and amphetamines activate VTA
5 limits of attention
- **Orient **– ability to locate specific sensory information from among many competing stimuli- lights and listening to her
- Divide attention – ability to attend to 2 or more things simultaneously (driving while listening and participating in conversations)
- Selectively attend – ability to avoid distraction to focus on important information
- **Sustain attention **– ability to pay attention over time (3- hour lecture)
- Switch attention – ability to switch readily from one task to another
what structures are reposnsible for motivation and what system is this called?
limbic system- integrates memories and thoughts to drive motivation and behaviors.
hypothalamus, thalamus, amygdala, hippocampus (integrates info)
Functions of Limbic System
- Feeding chewing and licking (especially in animals and young humans)
- Emotions- fear, sweating, Pupillary dilatation
- Autonomic function - changes heart rate, B.P, respiratory rate in response to stimuli and surroundings
- Rage and calmness (emotions)
- Regulation of biological rhythm - Body temp, urine vol, electrolyte balance
- Maternal behavior - Prolactin release, Lactation
- Motivation- Reward and Punishment
- Sexual functions
Functions of the Amygdala
- Behavioral awareness areas = Window of limbic system
- wide afferent connections with visual, auditory association areas - visual, auditory- see surroundings and make judgement call
- Wide efferent connections
Effects of stimulation = Coordinated behavioral, autonomic and endocrine responses
* Feeding and drinking
* Fighting behavior
* Attraction and maternal care
* Responses to physical or emotional stresses
* Relate environmental stimuli to coordinated behavioral responses
mood disorders
group of clinical conditions that cause extreme changes in a person’s mood, energy, and behavior.
is a state of (PERSISTENT AND PERVASIVE) low mood WITH INTENSE DISLIKE to activity or apathy that can affect a person’s thoughts, behaviour, feelings and sense of well-being
Depression
Neurotransmitter Systems in Depression
- Serotonin (5-HT) – SSRI- main treatment for depression
- Norepinephrine
-
Dopamine
* Glutamate- emerging evidence - Decreased availability of NT= linked to depression
depression caused by bad situations in a person’s life (loss, illness, tragedy)
- Situational and temporary without treatment
- Most people will deal with reactive depression at some point.
Reactive depression- situation dependent
based on a chemical imbalance in the brain, which can cause depression to develop even if there is no specific event to set it
* Risk of depression higher with family history
Biological depression- brain centric
one or more episodes of low mood
Unipolar Depression
Patient experience elevated mood, and increase in quantity and speed of physical and mental activity
Mania
patient experiences both low mood (depression) and abnormally elevated mood (hypomania or mania)
bipolar disorder
an episode of **manic symptoms **that does not meet the criteria for manic episode
Hypomania
**disorder that represents less severe forms of bipolar disorder- cycle through high and low moods
Cyclothymia
disorder that represent less severe forms of major depression- low mood but not clinical depression
Dysthymia
*** at least 2 years of depressed mood **
* not sufficiently severe to fit the diagnosis of major depressive episode.
Dysthymic disorder
at least 2 years of frequently occurring
- hypomanic symptoms cannot fit the diagnosis of manic episode
- depressive symptoms that cannot fit the diagnosis of major depressive episode.
Cyclothymic disorder
what NTM are involved in depression and chornic pain?
NE and 5-HT inc = pathophysiology for chronic pain
also the dopamine in the limbic system in midbrain affects motivation
(dec dopamine in chronic pain)
glutamate and its recptor subtypes (NMDA and AMPA) are found in chronic pain and depression
