Exam 3 Flashcards
What are the five different senses
sight taste smell hearing somatosensory
what kind of stimuli is sight responsive to
light stimuli
what kind of stimuli is taste responsive to
chemical stimuli
what kind of stimuli is smell responsive to
chemical stimuli
what kind of stimuli is hearing responsive to
mechanical stimuli
what kind of stimuli is somatosensory or touch responsive to
mechanical stimuli
The three different kinds of sensory receptors
photoreceptors
chemoreceptors
mechanoreceptors
photoreceptors are associated with
vision; converting light energy into action potentials
mechanoreceptors are associated with
touch, and hearing;converting mechanical energy into action potentials
chemoreceptors are associated with
taste and smell; convert chemical energy into action potentials
the factors influencing receptive field sensitivity
individual receptor sensitivity
density of the receptive field
individual receptor sensitivity
different types of receptors have different sensitivities
ex: rods are more sensitive than cones
stimulus intensity is coded
greater intensity like brighter light or louder noise encoded by a greater discharge rate
ex: with brightness it sends out more action potentials to adjust your eyes to light
stimulus quality is coded
type of the receptor tells the brain the quality/nature of a stimulus
ex: greater quality differentiation for the greater levels received by specific colors receptors
Sensation
the registration of physical stimuli from the environment by the sensory receptors
perception
the subjective experience of sensation
Factors contributing to perception
- nature of sensation
- context in which sensory events take place
- our emotional state
- past experiences and memories
Fovea
the region containing the largest density of photoreceptors; vision is actually sharpest here; makes up 1% of visual field
saccades
moving your eye to move your visual file to focus your fovea
blind spot
a region in your retina with no photoreceptors because of the optic nerve exiting the eye
Are photoreceptors hyper-polarized or depolarized by light
The more light hits the photoreceptor the more Na+ channels is will close, the more HYPERPOLARIZED a cell will be, the less glutamate will be released
rods
light sensitivity, size/shape, their functions, and what numbers of photopigments they contain.
more sensitive to dim light (night vision); only one type of pigment, responsible for night visions, large and cylindrical
cones
light sensitivity, size/shape, their functions, and what numbers of photopigments they contain.
more responsive to bright light; see fine detail and color; smaller; less sensitive; helps with motion; 3 types of light pigment ; smaller and tapered at the end
The different neurons involed in the neural relay for the visual system
photoreceptor -> striate cortex
light enters through the visual system-> photoreceptors (rods and cones)-> action potential from photoreceptors or either high low glutamate->horizontal cells (converge infor from receptors)->bipolar cells->acramine cells (converges from bipolar cells)-> retinal ganglion cells -> to the striate cortex
What is the ventral stream and where does it send info
the “what” path object identification
sends info to the temporal lobe
what is the dorsal stream and where does it send info
the “where” path, spatial location
sends info to the parietal lobe
What are 3 different effects of temporal lobe lesions on visual processing
visual cortex form agnosia
achromatopsia
akinetopsia
visual cortex from agnosia
inability to recognize objects from their shape
achromatopsia
inability to detect any colors
akinetopsia
inability to percieve movement or moving objects
The “where” information is processed int eh dorsal stream of the visual system
leaves the visual cortex through dorsal stream to the posterior parietal cortex. Recieveing ifno from the striate cortex and sends and recieves input from the moron and somatosensory cortex’s – allowing us to locate ourselves in space
The different effects of posterior parietal lobe lesions on visual functioning
apraxia
hemispacial neglect
defects in spatial memory, visual traching and visual attention
apraxia
inability to execute controlled movements
hemispacial neglects
lesion to the left - no longer able to use the right side of body
bottom-up processing
building up a mental representations the world based on if received by the senses and assembled through successive processing steps
top-down processing
our brain constructs representation of the world and then uses info from then uses info from the senses to the support or refute these constructs
Amplitude
tells us the volume of teh sound
frequencies
tells about the pitch
low frequency
lower pitch (long wavelengths)
high frequency
higher pitch (shorter but more frequent wavelength)
high amplitude
loud sound
low amplitude
soft sound
simple
pure tone
complex
mix of frequencies
The volume and pitch of sound are vonverted into changes in action potential firing in the auditory sense
the more amplitude the greater number of action potentials
the higher the pitch a more rapid cycle of action potentials
how sound vibrations are converted into changes in action potential firing by hair cells in the cochlea, specifically the role of K+ and K+ channels in this process
bending of hair cells one way opens k+channels on hair cells
- that depolarizes cell because in these cells K+ is higher OUTSIDE THE CELL
- the depolarization opes voltage gated gated Ca2 channels
the two ways volume or loudness influence action potential firing of auditory neurons.
Volume: loud noises bend the hair cells back and forth further. The louder the greater number of action potentials. The louder the more neurons there are producing actions potentials
Pitch- a more rapid cycle of action potentials; how fast the hair cells move back and fourth
(ALSO: they have a greater number of action potentials and a greater number of neurons producing those action potentials)
he name/location of the primary sensory cortex for taste
the insular cortex located between the frontal and temporal lobes
he name/location of the primary sensory cortex for smell
piriform cortex
he name/location of the primary sensory cortex for
the auditory cortex–temporal lobe
the five different tastes
sweet salty sour bitter umami
what specific chemical signals that sweet responds to
bids to glucose
what specific chemical signals that salty responds to
Na+ enters cell
What specific chemical signals that sour responds to
H+ ion enters cell
what specific chemical signals bitter responds to
binds to a wide range aromatic compunds “our poison detector”
what specific chemical signals bitter responds to
binds to amino acids glutamate
the different variables affecting taste
emotional states
past experiences
genetics
saliva
emotional states
when we’re feeling sad or anxious, food tastes less good– comfort food
past experiences
foods that have sickened us taste less good, new strange foods taste less good than familiar ones
genetics
some people have certain taste proclivities and aversions particularly for bitter taste
How does smell affect human behavior
eating behaviors
sensing danger
sex and social behavior
eating behaviors
good or bad smelling food may encourage or discourage us from eating
sensing danger
fire or predator scent
sex and socail behavior
scent of receptive females sled, kin, strangers of our own species
The main neural structures involved in the neural control of movement
Frontal cortex
-Basal Ganglia
-Cerebellum
Brainstem
spinal cord
muscles
somatosensoryMovement - Frontal cortex –Basal ganglia and Cerebellum
FC- iniates and plans movement
BG- regulates the force of movements
C- detects and corrects errors in movement
Brainstem
relays commands to the spinal cord
spinal cord
transmits signals to lower motor neurons
muscles
carry out movements
Somatosensory system
provides feedback about movement
The three main parts of the frontal cortex
prefrontal cortex
premotor cortex
motor cortex
prefrontal cortex
initiates movement goals
premotor cortex
organizes movement patterns plans out movement
motor cortex
actually sens out the comman ds for producing specific movements through different patterns of muscle activation
(carries out the plan)
How would lesionas affect the function of prefrontal cortex
gives you impaired judgement; having trouble getting rid of bad plans
How would lesions affect the function of the premotor cortex
trouble putting together patterns movement; can still do stuff but they can’t put together patterns of movement
how would lesions affect the function of the motor cortex
paralysis or inability to carry out specific movements
agonists
a muscle that causes specific movement or possible several movements to ocur though the process of its contraction (Pulling and causing of a movement )
antagonists
a muscle that acts in opposition to specific movement generated by the agonist
muscle
consists of long cylindrical cells (muscle fibers) , which pull on each other causing contracting or shortening of muscle fibers
motor unit
multiple muscle fibers
the tow different types of movement symptoms associated with damage to the basal ganglia
hyperkinetic symptoms
hypokinetic symptoms
WHich disease is associated with hyperkinetic symptoms
Tourrette’s syndrome ; the tics
Huntington’s (chorea)
Which disease is associated with hypokinetic symptoms
Parkinson’s disease
which pathway is associated with hyperkinetic symptoms?
direct pathway
which pathway is associated with hypokinetic symptoms
indirect pathway
what is the role of the basal ganglia in force correction
knows plan of movement and weighs with movement occurring- either increases or decreases the force of the movement by increasing or decreasing its drive to the thalamus.
What is the role of the cerebellum in movement error correction
- the cortex sends movement info down the spinal cord to muscles
- the cerebellum also receives a copy of this motor program from the cortex via the inferior olive
- the cerebellum then sends corrective feedback to the premotor cortical neurons so that the next time the motor program is send down it is adjusted based on this sensory feedback and experience
What are the four different types of somatosensory info
nocioception
thermoreceptor
hapsis
proprioception
what does nocioception respond to
(skin) pain
what does thermoreceptors respond to
(skin) temperature
What does hapsis respond to
fine touch and pressure
what does proprioception respond to
(muscles, tendons and joints) body awareness, muscle stretch and joint angle
Rods and convergence
- more rods converge on each bipolar neuron and more rod bipolar neurons converge on each rod ganglion cell
- rods are important for sensing dimlight so more convergence make sese since it means more bipolar neurons will be activated if any rods get activated by light
- convergence makes the rod system a better detector of light because small signals from many rods are pooled to generated a large response in the bipolar cell
Cones and convergence
cones are important for fine detail discrimination so less convergence makes sense if we want a fine map of an object
the different functions of the dorsal stream and posterior parietal cortex
- localization of objector in in the body in space
- producing planned movements
- spatial memory (where things are)
- visual attention (being able to follow/ track a moving object)
How does the process of line detection take place by retinal ganglion cells
Each retinal ganglion cell receives input from a number of nearby bipolar cells, which receive input from a number of nearby photoreceptors
Thus each ganglion cell has a distinct receptive field of photoreceptors which will be activated if light hits them and will activate that ganglion cell
The retina therefore consists of thousands of receptive fields
How is line information summed to provide line detection in the primary visual cortex
Each cell in the visual striate cortex receives input from several retinal ganglion cells
Input from several ganglion “spot” cells sum and activate a single neuron in the temporal cortex
This becomes translated into lines
Different neurons respond to different line orientations
Neurons responding to lines in different parts of the visual cortex are arranged into columns in the visual cortex
WHere are how line info converges to provide shape detection in the visual system
Input from the striate visual cortex is sent to the inferior temporal cortex via the ventral system
Input from many different “line” neurons integrate onto a single inferior temporal cortical neuron that processes these individual lines or edges into shapes
HOw is sound perception lateralized in the brain
- sensory neurons in the cochlea send axons to the neuron in the nuclei in the brainstem
- the brainstem neurons send axons to the neurons in the midbrain
- the neruons in the midbrain send axons to the thalamus
- the thalamic neurons to the auditory cortex in the temporal lobe
- the auditory info crosses over oposite sides of the
which side of music and language are processed on
speech and language are processed in the left temporal lobe. music is processed in the right temporal lobe
what are the main components of human thought or cognition
perception
attention
memory
executive functions
perceptions
the ability to recognize and interpret sensory stimui
attention
the ability to sustain concentration on a particular object, action or thought
memory
the ability to store and recall info
executive functions
abilities that enable goal oriented behavior such as abliity to plan and execute a goal , impulse, problem sovling coming up with new ideas etc
what are the methods by which cognition is studied
psychological testing, brain imaging, psychophisiological methods
what different types of phsychological tests are used for studying which aspects of cognition
perception (how long to recognize objects), attention (how long a subject focuses on something), memory (remember#’s words, symbols and executive function tests ( are people sucessful in solving a particular problem)
MRI
measures size or volume of different brain regions
FMRI
measures change in blood flow to the brain regions and allow us to quantify the amount as well as localizaiton of brain activity in response to a particular cognitive task
PET
can measure GLUCOSE UTILIZIATION and allow us to quantify the amount as well as the localization of brain activity in response to a particular cognitive task
EEG
the recording of electrical activity of the brain through scalp electrodes
it tells us about the timing and magnitude of neural activity in the brain but not where the activity is coming from
What are the two different brain areas involved in language comprehension and formation
Wernicke’s area
Broca’s area
Wernice’s area
in the left temporal cortex, responsible for language comprehension
broca’s area
in the lower left frontal cortex; responsible for language production/formation
how is language lateralized in the brain
language comprehension is laterlaized in the lower left frontal cortex and is responsible for speech production. it receives input from wernicke’s area, memroy areas (like the hippocampus) and prefrontal cortex about identity of words and their meaning and activates neurons in the motor cortex that activates lips, tongue, pharynx etc to prduce correct sound
Which sicde is important for literal communiation
the left temporal lobe is important for understanding and creating literal language
which side is important for insincere communication
the right temporal lobe is important in detecting lies, sarcasm innuendo humor and other forms of insincere communication
The functions of the anterior cingulate cortex
a set of neurons that are activated by sensory input that is novel, complex, conflicting, and aversive or unrewarding and sends output to the PREFRONTAL CORTEX to develop a new plan
WHen does the anterior cingulate cortex be more active
when a task is difficult or unfamiliar and when a subject is focused rather than distracted or anxious
What are the different congnitive behaviors afiliated with the associate cortex ?
Planning and impulse control language comprehension and reading Problem solving attention imitation and understanding
what cortical areas are associated with language comprehension and reading
wernicke’s area, broca’s area, left and right temporal lobe and prefrontal motor cortex
what cortical areas are associated with problem solving
anterior cingulate cortex, prefrontal cortex, cerebllum and basal gangila motor cortex
what cortical areas are associated with planning and impulse control
prefrontal cortex; premotor cortex
what cortical areas are associated with attention
parietal association cortex, anterior cingulate cortex
what cortical areas are associated with imitation and understanding
prefrontal cortex, sensory cortex, mirror neurons, left temporal lobe
Mirror neurons
cortical neurons that fire when a movement is made or when the same movement is seen to be made by another
Cognitive functions of mirror neurons
Imitation and understanding
development of language, recognition and understanding of facial expressions and gestures and sounds
understanding the intentions of others giving us empathy
Convergent intelligence
parietal and temporal lobe
the ability to apply memory or reasoning kill to come up with the correct answer
divergent intelligence
the ability to use uncontentional knowledge a creative approach to come up with novel solutions
What are the brain changes in ADHD
- reduced size and connectivity of the PREFRONTAL CORTEX
- decreased volume in the stratum of basal ganglia wich is involved in motivation as well as inhibition of impulse motor behavior (hyperactivity)
- decreased amygdalal size and connectivity which could contribute to problems with emotional regulation
What are the neurotransmitters involved in ADHD
Dopamine
Acetylcholine
Norepinephrine
Glutamate
Dopamine and ADHD
decreased signaling results in decreased reward pathways that may cause children to seek out new stimuli for greater reward increased impulsivity
Acetylcholine and ADHD
decreased signaling may decrease attention
Norepinephrine and ADHD
decreased signaling may decrease arousal in response to certain sensory cues
Glutamate and ADHD
in signalng may increase arousal and thought in the brain
brain changes in schizophrenia
- smaller brain size and larger ventricles
- specifically the prefrontal cortex and cingulate, hippocampus and medial temporal cortex and smaller (regions associated with cognition, memory and emotional regulation
What are teh different hypothesis regarding neurotransmitters and shcizophrenia
Dopamine hypothesis
Glutamate hypothesis
Dopamine hypothesis
brain of shcizo may have incerased dopamine signaling, dopamine receptor levels are increased in the frontal cortex and striatum
-dopamine receptors antagonists are effective theraputic agents for schizophrenia wihle amphetamiens promote the release of dopanine which can exacerabe schizo symptoms
glutamate hypothesis
brains of schizophrenics may have increased glutamate signaling
- glutamate is used though out the brain and especially the cortex as an exicatory NT
- excessive glutamate release onto the neruons may randomly increase their firitn in a way tha increases random thoughts and sensations thus producing the irrational way thought process and hallucinations of schizo
- excessing glutamte levels an also reslut in death of neurons by glutatmte exitocicity
positive symptoms of Schizo
what they have that we don’t have
hallucinations
delusion
paranoia
disorganized though and speech
negative symptoms
less treatable have biggest negative impact on quality of one’s life
blunted emotional responses
social withdrawal
catatonia
the neural changes of schizo
disorganization of hippocampal and cortical neruons
decreased cerebral myelination and oligoendrocyte function
reduced dendrite and axon formation in the cerebral corex
the brain changes occuring with cognitive decline with aging
- decreased performance on cognitive tests of memory perceptions attentional and executive function
- decreased brain volume, particularly in anterior brain regions in cortical regions
What are the nerual changes occurring with cognitive decline with aging
decreased myelination of cortical neurons
loss of neurons throughout the brain from normal wear and tear
decreased neruongensis in the hippocampus
Neruodiversity
the approach to learning and disablity which suggests that diverse neurlogical conditions appear as a result of hormonal variation of the human genome
Neurodiversity hypothesis
Hunter Farmer Hypothesis (ADHD) Shaministic Hypothesis (Schizo)
Hunter Farmer Hypothesis (ADHD)
Having a distributed attention style was adaptive for hunter gatherers
hunters bring back food to the trive so they have to be hyperfocused and hypersensitive as well as very creative as succeesd in catching their prey
-farmers have a routine day to day life style so being super focused isn’t very necessary
Shamanistic Hypothesis
Seeing visions and hearing voices may have been beneficial for shamans in tribal socieites
