Brain and Behavior test 3 Flashcards
Tz
Means treatment
Sx
Means symptoms
Rs
Means receptors
Schizophrenia
- abnormal perception of reality
- lucid and actively psychotic alternating
- symptoms mid 20s
- effects 1% of population
- genes/environment, maternal-many theories about causes
Positive schizophrenia symptoms
- delusions/false beliefs
- hallucinations
- disorganized speech (echolalia, tangential speech etc)
- disorganized behavior (Catatonia)
- disorganized thought
Negative schizophrenia symptoms
- inappropriate/flat affect
- alogia
- avolition
- anhedonia
- in attention
Alogia
A poverty of speech
Avolition
Lack of motivation/apathy
-lack of personal hygiene
Anhedonia
Lack of interest in pleasurable activities
Dopamine hypothesis of schizophrenia
- too much dopamine leads to positive symptoms
- too little dopamine related to negative symptoms
Brain abnormalities in schizophrenia
Enlarged ventricles
-diffuse cortical atrophy
Gray matter loss
Schizophrenia treatments
Dopamine antagonists
- block receptors
- involuntary movements are side effects
Tardive dyskinesia
Lip smacking, involuntary movements
Atypical antipsychotics
Treatment of schizophrenia
- block dopamine receptors selectively
Neuroleptics
Used to treat schizophrenia, not clean drugs though
Affective disorders
Mood disorders
Mood disorders
Commonly co-morbid with other diseases, anxiety/depression overlap and meds overlap
Best Outcome for Mood Disorders
Medications and psychotherapy and cognitive behavioral therapy
Cognitive Behavioral Therapy
Relaxation techniques, challenging thoughts and increasing awareness, biofeedback, desensitization
Major Depressive Disorder
Reactive to trauma, seasonal effective disorder, 5+ symptoms for at least 2 weeks
Symptoms of major depressive disorder
-depressed mood, anhedonia, change in appetite, feelings of worthlessness/guilt, change in sleep, less concentration, restlessness, fatigue, suicidal ideation
Monoamine Hypothesis for major depressive disorder
Low serotonin, abnormal beta
- drugs up serotonin
Antidepressants
Serotonin reputable inhibitors, block other neurotransmitters
Prozac
Selective serotonin reuptake inhibitors
Effexor
Selective serotonin reuptake inhibitor
Bipolar disorder
Formerly manic depression, cycles of mania and depression
Treatment of bipolar disorder
Mood stabilizers- lithium, antipsychotic
- elctroconvulsant therapy
- psychotherapy
Anxiety Disorder
Frequently comorbid with depression and treated with anti anxiety and anti depressives
GABA antagonists
Treat anxiety, sedating, barbiturates
Side effects- risk of death by respiratory depression when mixed with alcohol, anti-seizure drugs etc
Beta blockers
Reduce sympathetic nervous system arousal
-used to treat anti anxiety
Generalized Anxiety Disorder
Anxiety that is not localized to a single root but rather about daily events/activities for more than 6 months
Treatment: psychotherapy, benzodiazepines, Wellbutrin. With SSRIs
Specific Anxiety
Phobias, panic disorder
Phobias
Fear of specific object or idea
-treatment: systematic desensitization
Panic disorder
Characterized by panic attacks
- sense of impending doom, sweating, chest pain
- sometimes with agoraphobia
- treatment: acute panic–> SSRIs and CBT
OCD (obsessive compulsive disorder)
- recurring thoughts
- compulsions
- ego-dystonic
Treatment: SSRIs with cognitive behavioral therapy
Obsessions
Intrusive, recurring thoughts
Compulsions
Behaviors done to stop obsession.
- excessive cleaning because believing about contamination
- doubt
- symmetry- slow methodical performance
Ego-dystonic
Have insight the unreasonable-ness of distress and time consumption
- symptom of OCD
PTSD ( post traumatic stress disorder)
- after direct threat or witnessing
Symptoms: flashback, nightmare, avoidance, social detachment, flattened affect, exaggerated startle response
Treatment: psychotherapy and SSRIs
Sites where no blood brain barrier
Pineal gland, pituitary gland, area postrema
Types of Senses
Auditory, mechanical, chemical and vision
Mechanical
Vestibular (balance), somatosensory (touch, pain, temp, pressure, body position)
Chemical
Taste, olfaction (smell), vomeronasal (detection of pheromones)
Detection of sense
Requires receptors specialized for that stimulus modality
Transduced
Changing from stimulus to language neurons can speak
Coding
Coding of senses
Transport of sensory Information
Information that goes from the periphery nervous system to the cortex (often via the thalamus)
Sound and the ear
Audition depends on ability to detect sound waves
-periodic compressions of air, water other
Amplitude
Intensity of the sound wave
Loudness
Perception of the sound wave
Frequency
The number of compressions per second, measured in hertz (related to pitch)
Outer Ear
Includes the pinna, the structure of flesh and cartilage attached to each side of the head
Pinna
Part of outer ear that’s responsible for altering the reflection of sound waves into the middle ear from the outer ear
-helps us locate the source of the sound
Middle Ear
Contains tympanic membrane (ear drum) and three tiny bones
Tympanic Membrane
Ear drum, which vibrates at the same rate when struck by sound waves
Oval Window
Membrane in the inner ear, transmits waves through the viscous fluid of the inner ear
Inner Ear
Snail shaped structure called the cochlea, which contains three fluid - filled tunnels
-hair cells
Cochlea
Part of inner ear. Contains three fluid-filled tunnels
Hair Cells
Auditory receptors that lie between basilar membrane and tectorial membrane in the cochlea
Basilar Membrane
Part of the cochlea, hairs between it and the tectorial membrane t
Tectorial Membrane
Hair cells between this and basilar membrane in the cochlea
How we hear:
Sound through auditory canal, strike drum and vibrations transmitted
Membranes caused to bend by waves, making cilia bend
Bend opens Ca+2 ion channels
Neurotransmitters released from hair cells, stimulates auditory nerve (part of 8th cranial nerve)
Neuronal impulses travel to auditory cortex
Primary Auditory cortex
Located in the superior temporal cortex
- destination for most information from auditory system
- place where auditory coding occurs
- most info comes from opposite side ear
Damage to A1
Damage to primary auditory cortex doesn’t cause deafness unless it extends to sub cortical areas
-provides tonotopic map
Tonotopic Map
In auditory correct, shows which cells in primary auditory cortex (a1) are more responsive to preferred tones
Amusia
Tone deaf? Can’t tell tones, don’t detect wrong notes
Associated with thicker auditory context in right hemisphere but fewer connections from auditory to frontal cortex
Perfect Pitch
Absolute pitch, ability to hear a note and identify it
- maybe generic
- early and extensive musical training
- more common among people who speak tonal languages
Two types of hearing loss
1) Conductive or middle ear deafness
2) nerve deafness or inner ear deafness
Conductive/middle ear deafness
When bones of middle ear fail to transmit sounds properly to cochlea
Caused by disease, infection, tumerous bone growth
-correct with surgery or hearing aids
-when normal, people hear their own voice clearly
Nerve or inner-ear deafness
Damage to cochlea, hair cells or auditory nerve
- vary in degree
- can be confined to one area of cochlea leading people to hear only certain frequencies
- inherited, prenatal problems or early childhood disorders
Tinnitus
- frequent/constant ringing in ears
- happens to people with nerve deafness or damage to cochlea
Vestibular system
Respond to mechanical stimuli which indicate the position and movement of head
-balance
Vestibular sensation
Directs compensation movement of the eye and helps to maintain balance
Otoliths
Calcium carbonate particles that push against different hairs and excite them when head tilts
-in the vestibular system
Vestibular canals
Three semicircular canals filled with jellylike substance and hair cells that are activated when head moves, action potentials travel to the brain stem and cerebellum
Somatosensation
Sensation of the body and its movements.
-many sensations: touch, pressure, temperature, pain, itch, tickle and position and movement of joints
Somatosensory receptors
Nociception-pain
Hapis- fine touch and pressure
Proprioception- location and movement of body
Nociception
Perception of pain and temperature, one of three somatosensory receptors
Hapis
Perception of objects that are grasped and manipulated or contact with the body, called perception of fine touch and pressure
-1 of 3 somatosensory receptors
Proprioception
Perception of the location and movement of the body
- 1 of 3 somatosensory receptors
Auditory coding
Occurs in the auditory cortex
Somatosensory transduction
Stimulation of receptors opens sodium channels to trigger an action potential
Dermatome
The skin area connected to or inverted by a single sensory spinal nerve
Touch receptors in head
Information from touch receptors in head enter the central nervous system through the cranial nerves
Below the head touch
Information from receptors below the head enters the spinal cord and travel through the 31 spinal nerves to the brain
Somatosensory input to brain
Specific pathways, dedicated to different sensations, transfer Neural info to brain via ascending ipsilateral pathway
Ipsilateral pathway
The way neural info gets to the brain about somatosensory stimulation
Pain
Somatosensory information, wide range (dull to sharp), harmful stimulus
Nociceptors respond to pain
Nociceptors respond to:
Pain, as part of the somatosensory system
-Heat, cold, acids, etc
Capsaicin
Something from papers that nociceptors feel
-when rubbed on sore joints produces temporary burning sensation which turns into decreased pain
Axons and pain
Axons carrying pain information have little or no myelin, impulses travel slowly but brain responds quickly
Mild pain
Triggers release of glutamate on the spinal cord
Strong pain
Triggers release of glutamate and substance p
Pain pathways
- contra lateral to side of spine
- go to somatosensory cortex for perception
- go to limbus structure for emotional aspects of pain
Opiates & Pain
Opiate receptors blocks the release of substance P in the spinal cord and in the periaqueductal gray areas of the midbrain
Endorphins
Called endogenous morphines
Group of chemicals that attach to the same brain receptors as morphines
Enkephalin
Interacts with pain in somatosensory system
This decreases substance p (pain) activity via presynaptic inhibition
PAG
Periaqueductal grey
Periaqueductal grey (PAG)
Electrical stim has pain stopping effects through endorphin-sensitive circuit
-interneurons inhibit incoming pain signals
Gate Theory of Pain
Considers that spinal cord areas that receive messages from pain receptors also receive input from touch receptors and from axons descending from the brain
(Meaning no pain stimuli around pain can decrease the intensity)
Placebo
Drug or other procedure with no pharmacological effect
Decreases pain anyway
Cannabinoids
Chemicals related to marijuana that block certain kinds of pain in the periphery of the body
Sensitization to Pain
Damaged or inflamed tissue are more sensitive because of histamine (nerve growth factor)
-anti-inflammatory drugs decrease the release of such chemicals
Chronic Pain
Certain receptors become potentiated after really intense pain and respond more vigorously to stimulation
Emotional Pain
Resembles physical pain
- increased activity in the cingulate cortex when someone feels left out
- taking Tylenol actually makes people report less social pain
Neuropathic Pain
Severe chronic pain in the absence of recognizable pain stimulus
- likely from pathology of nervous system linked to an injury
- maybe aberrant glial cells triggering pain pathways
Itch
Release of histamine a by the skin produces itching
- has distinct neural pathway in the spinal cord to brain
- impulses slow
- itch or pain, not both
Chemical senses
Each chemical stimulus excites several kinds of receptors
Amount of olfactory receptors
Hundreds
Pheromone receptor amount
Not olfactory, there are different ones
Amount of taste receptors
Five different:
Sweet, salty, bitter, sour, umami (MSG type salty)
General issues about chemical coding
Each chemical excites several kinds of receptors, meaning response depends on context of responses by others (eg flavor= combination of taste and smell)
Adaption of chemical senses
Reduced perception of stimuli due to fatigue of receptors (getting used to bad smell)
Cross-adaptation
Chemical senses refers to reduced response to one stimuli after exposure to another
Papillae
Structures on the surface of the tongue that contain the taste buds
- 10 or more taste buds, each with 50 receptors, they’re modified skin cells
- outside edge of tongue
Transduction of salty
Neuron carries impulse from taste bud, salty allows sodium ions to pass through membrane and info passes to brain
Sour sensory transduction
Neuron away from taste bud, causes close in k+ channels preventing it from leaving cell
(Depolarization)
Sweet, bitter, umami sensory transduction
Activate metabotropic mechanisms
Taste pathway
Different areas respond different ways, process taste info
- somatosensory cortex responds to touch on tonge
- insula is primary taste cortex
Olfaction
Critical to most animals for food, mates, danger
Many different receptors, new receptors throughout life
Olfactory System
- receptors on cilia of neurons in nose
- things that smell similar excite close areas on olfactory bulb,
- coding in brain determines where is excited
Sensory transduction in olfaction
Proteins in olfactory receptors respond to chemicals outside cell and trigger changes to G protein inside
-G protein triggers chemical activities that lead to action potentials
Olfactory Nerve
Axons of each olfactory cell joins with axons of other olfactory receptors and form this nerve
Neural pathway of olfaction
Olfactory nerve carries neural info to olfactory bulb which projects via olfactory tract to the pyriform cortex near amygdala (close relationship for emotional aspects and smell)
Coding of Olfaction
Occurs in the pyriform cortex
Vomeronasal Organ (VNO)
Receptors located near, but separate from the olfactory receptors
(Tiny in human adults, but maintains their response to stimuli)
Pheromones
Chemicals released by an animal that affect the behavior of other members of the same species
Conspecifics
Members of the same species
Synesthesia
Experience of one sense in response to stimulation of different sense (bread tastes blue)
Visual Coding Reception
Absorption of physical energy by receptors, requires photoreceptors because physical energy being received is light
Visual coding and retinal receptors transduction
Done by Rods and comes which have the about to Change the photic energy into electrical energy
Transduction
conversion of physical energy to an electrochemical pattern in the neurons
Reception
Absorption of physical energy by receptors
Coding
One to one correspondence between some aspect of the physical stimulus and some aspect of the nervous system
Visual coding
Neural information occurs in the visual cortex
Superior colliculus
Retinal ganglion cells send info to here in the midbrain, up to the thalamus, then to different areas of the cortex
Anosmia
Can’t smell
Aguesia
Can’t taste
Amphetamine
Psychostimulat drug that increases wakefulness and focus
Effects reward systems
Acetylcholinesterase (AChE)
This actively terminates synaptic transmission
Atropine
Naturally occurring drug, belladonna
Benzodiazepine
Sedative, sleep inducing, anti anxiety
-used to treat alcohol withdrawal
Botox
Used to do lots of things, not just facials, treat muscle problems
Caffeine
Works through disinhibition, gives energy
Capcaisin
From peppers, used to help joint pain, burning sensation and then dulls pain
Causes the body to trigger an inflammatory response
Cocaine
Stimulant
It’s a dopamine reuptake inhibitor
Curare
Name for various poisons found in South America
Muscle relaxant, blocks acetylcholine receptors
Endorphin
Peptides that function as neurotransmitters, causes feelings of exhilaration
-excitement, pain
Resemble opiates
Enkephalin
They are endorphins
They bond to the body’s opioid receptors
Haloperidol
Dopamine antagonist (opposite of), used in treatment of schizophrenia
Monoamine Oxidase
They deactivate neurotransmitters
- without it, linked to many psychiatric disorders
Nicotine
Stimulant effect
Acts on nicotinic acetylcholine receptors and the central nervous system nicotinic receptors
Prozac
Selective serotonin reuptake inhibitor
Used to treat major depressive disorder
SSRI
Selective serotonin reuptake inhibitor
SSNRI
Serotonin-norepinephrine reuptake inhibitors
-mood disorders, anxiety, OCD
TCA
Tricyclic antidepressants - type of antidepressants that’s not used often, blocks serotonin transporter and norepinephrine transporter
Smooth muscles
Control digestive system and other organs
Skeletal/striated muscles
Control movement of the body in relation to the environment
Cardiac muscles
Have properties of skeletal and smooth muscles, heart muscles
Motor unit
Neuron and its innervated fibers
Axon can talk to many muscle fibers, but muscle fibers only talk to one axon
Neuromuscular junction
Synapse between motor neuron axon and muscle fiber
Neurotransmitter at neuromuscular junction
Acetylcholine
Acetylcholine binding to muscle receptors
Causes ionotropic response which makes causes muscle contraction
(Muscle relaxing is no response)
Antagonistic muscles
Movement requires the alternating contraction of opposing sets of muscles
Flexor muscle
A muscle that flexes or raises an appendage
Extensor muscle
One that extends or straightens an appendage (ie triceps)
Synergistic muscles
When muscles work together
Fast twitch
Skeletal muscle fiber type
Fast contractions, fatigue rapidly
-anaerobic
Anaerobic
Use reactions that do not require oxygen, resulting in muscle fatigue
Slow twitch
Fibers produce less vigorous contraction without fatigue
-aerobic
Aerobic
Use oxygen
-no fatigue on muscles
Muscle spindle proprioceptors
-receptors that detect position or movement, these in particular
Responds to a stretch, send message to spinal cord that results in contraction of muscle
Golgi tendon organ proprioceptors
-receptors that detect position or movement, this in particular increase muscle tension, tendons at opposite ends of muscle, act as brakes against excessively vigorous contraction by sending impulse to spinal cord and inhibiting motor neurons
Knee jerk reflex
Patellar tendon, type of stretch reflex
Stimulus: tapping tendon
Receptor: muscle spindle
Reaction: jerk knee, motor response
