Ch. 5-7Studyguide

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1. Mechanoreceptors

a sense organ or cell that responds to mechanical stimuli such as touch or sound

2. proprioceptors

pg.229

proprioceptor:a receptor that detects the position or movement of a part of the body. Ex: muscle proprioceptors detect the stretch and tension of a muscle and send messages that enable the spinal cord to adjust its signals.

3. thermoreceptors

thermoreceptor: termperature sensation

4. nociceptors

a sensory receptor for painful stimuli

5. pain perception

The first pain pathway sends signals via nerves about the intensity of painful stimuli to a number of regions in the brain that have typically been associated with pain perception, such as the anterior cingulate cortex

6. c-fibers

include postganglionic fibers in the autonomic nervous system (ANS), and nerve fibers at the dorsal roots (IV fiber). These fibers carry sensory information. Damage or injury to nerve fibers causes neuropathic pain.

7. a-delta fibers

carry cold, pressure, and acute pain signals, and because they are thin (2 to 5 μm in diameter) and myelinated, they send impulses faster than unmyelinated C fibers, but more slowly than other, more thickly myelinated group A nerve fibers. Their conduction velocities are moderate.

8. Describe the parts of the eye (e.g. pupil, lens, etc.)

pg.149

-light enters the eye through an opening in the center of the iris called a pupil.

It is focused by the lens and projected onto the retina.

-retina: rear surface of the eye,which is lined with visual receptors. has neurons

-fovea: a tiny area specialized for acute,detailed vision. aids perception of vision. Each receptor in the fovea connects to a single bipolar cell, which in turn connects to a single ganglion cell that has an axon to the brain.

9. Describe the different neurons involved in retinal processing(amacrine cells, bipolar cells, ganglion cells,etc.) and the order in which light passes through.

pg.149 anndd pg.165?

In the vertebrate retina, messages go from the receptors at the back of the eye to bipolar cells, located closer to the center of the eye. The bipolar cells send their message to ganglion cells, located still closer to the center of the eye. The ganglion cells' axons join together and travel back to the brain. Additional cells called amacrine cells get information from bipolar cells and send it to other bipolar, amacrine, and ganglion cells. Amcrine cells refine the input to ganglion cells, enabling certain ones to respond mainly to particular shapes, directions of movement, changes in lighting, color, and other visual features. The ganglion cell axons join to the form the optic nerve that exits through the back of the eye.

10. Describe the blind spot

pg.149

blind spot:has no receptors. brain fills in the gap. Anything blind spot in one eye, is visible to the other eye.

11. Describe the difference between rods and cones

pg.152

vertebrate retina contains two types of receptors.

rods: abundant in the periphery of the human retina,respond to faint light but are not useful in daylight because bright light bleaches them.

Cones: abundant in and near the fovea, are less active in dim light, more useful in bright light, and essential for color vision. Cones provide 90 percent of the brain's input. Each cone has its own line to the brain.

-rods to cones: 20 to 1

12. Describe Young-Helmholz/Trichromatic theory and the opponent process theory of color vision

pg.154

Young-Helmholz/Trichromatic theory:we perceive color through the relative rates of response by three kinds of cones, each one maximally sensitive to a different set of wavelengths. He decided on the number three because he found that people could match any color by mixing appropriate amounts of wavelengths.

13. Describe the function of the lateral geniculate nucleus of the thalamus and the superior colliculus

pg.162 and look in the notebook

-Most ganglion cell axons go to the lateral geniculate nucleus, part of the thalamus.A smaller number of axons go to the superior colliculus and other areas, including part of the hypothalamus that controls the waking-sleeping schedule. The lateral geniculate, in turn, sends axons to other parts of the thalamus and the visual cortex. Axons returning from the cortex to the thalamus modify thalamic activity.

14. Know the function of the occipital lobe

pg.84

occipital lobe:the posterior end of the cortex is the main target for visual information.

15. Know how visual information travels from the eye to the brain

(notebook) (pg.164)

1. A light wave hits retina and becomes neural energy.When light passes eye finally to rod/cones, and bounces back. ganglion cell is last then goes back to brain.

16. Know the role of V1, V2, V3, and V4, and V5

pg.166

V1: primary visual cortex:information from the lateral geniculate nucleus of the thalamus goes to this.Known as striate cortex because of its striped appearance.If you close your eyes and imagine seeing something, activity increase in area V1 in a pattern similar to when you see an actual object.People with damage to area V1 report no conscious vision, no visual imagery, and no visual images in their dreams.

pg.169

respond strongly to bar- or edge-shaped patterns.

pg.177

V1 sends info to V2

V2: secondary visual cortex: processes the information further and transmits it to additional areas. V2 returns information to V1.

pg.178

V2, just anterior to V1 in the occipital cortex, most cells are similar to V1 cells in responding to lines, edges, or sine waves gratings except that V2 receptive fields are more elongated. Some V2 cells repsond best to corners, or complex shapes.Some cells are highly responsive to color, and other cells highly responsive to the disparity between what the left and right eyes see-critical information for stereocopic depth perception.

V3: ventral posterior: Most are selective for orientation, and many are also tuned to motion and to depth. Relatively few are colour sensitive

v4:It receives input mainly from the thin and interstripe regions of V2, but also has connections from V1 and V3.Although the area contains many cells that are colour selective, indicating a role in colour analysis, cells are also found with complex spatial and orientation tuning, suggesting that the area is also important for spatial vision. (responsible for color/ people who cant see color,can only see black and white)

v5:middle temporal:Most cells in MT are tuned to motion, and the area can be divided into direction and 'axis of motion' columns. The connections from V2 are puzzling, because few cells there are motion selective. Nevertheless, many agree that MT is intimately linked with the analysis of image motion. (responsible for seeing motion)

17. Describe the ventral and dorsal streams in visual processing

-Dorsal stream responsible for knowing where objects are. Ventral stream sends projections, and knowing "what " objects are.

18. Know visual agnosia and prospagnosia

propagnosia: can't recognize faces.

pg.179

visual agnosia: an inability to recognize objects despite otherwise satisfactory vision. Common result from damage in the temporal cortex.Someone might be able to point to visual objects and slowly describe them but fail to recognize what they are.

19. Describe how we see in 3 dimensions

pg.171

stereoscopic depth: seeing 3 dimensions. Can see 3D because we can see in retinal disparity. Each eye takes a different look of parts of the world. retinal disparity: the discrepancy between what the left and right eye sees.

20. Describe the difference between sound intensity and sound pitch

pg.188

amplitude: sound wave of intensity. loudness of sound.

pitch: sounds higher in frequency are higher in pitch. frequency: a sound is the number of compressions per second, measured in hertz.

21. Know the parts of the ear (e.g. pinna, tymphanic membrane, maleus incues, stapes, etc.)

pg.189

pinna: outer layer of the ear. help us locate the source of sound. made to funnel sound.

After sound waves pass through the auditory canal , they enter the middle ear. When sound waves reach the middle ear, they vibrate the

tympanic membrane: ear drum. It connects to three tiny bones that transmit the vibration to the oval window(membrane of the inner ear.)

The smallest bones in the body are sometimes known as malleus, incus, and stapes.

When the stirrup vibrates the oval window, it sets into motion the fluid in the cochlea.

cochlea: snail shaped structure of the ear. vibrations in the fluid of the cochlea displace the hair cells, thereby opening ion channels in its membrane.

hair cells:i lie between the basilar membrane of the cochlea on one side and the tectorial membrane on the other.

22. Know the function of the vestibular system

pg.199

Sensations from the vestibular organ direct the direction of tilt and the amount of acceleration of the head. You use that information automatically for guiding eye movements and maintaining balance.

vestibular system: balancing system.

23. Know the function somatosensory cortex and the homunculus

pg.199

somatosensory system: the sensation of the body and its movements, is not one sense but many, including discriminative touch(which identifies the shape of an object), deep pressure, cold, warmth, pain, itch, tickle, and the position and movements of joints.

pg. 200

The body has specialized receptors to detect temperature, a critical variable to monitor, given that overheating or overcooling the body can be fatal.

24. Describe the function of the ACC and the insula

25. Describe supertasters and synthesia

pg.214

supertasters: people with more tastebuds. tend to strongly dislike flavored foods, especially food that taste very bitter to them, but only mildly bitter to other people.

pg.220

synesthesia: the experience some people have in which simulation of one sense evokes a perception of that sense and another one also. Disorder, experience 2 sensory processes at the same time.

ex: hear tone, taste things

26. Describe Martha McClintock's study on pheromones

27. Describe the function of the pfc

pg.236

prefrontal cortex: involved with planned movements, organizing, perception, and reasoning. active during a delay before a movement, stores sensory information relevant to a movement.

28. Describe the function of mirror neurons

pg. 236

mirror neurons: active both during preparation for a movement and while watching someone else perform the same or a similar movement. deal with empathy. may be important for understanding other people, identifying with them, and imitating them.

29. Describe the function of cerebellum

pg.239

cerebellum: latin for little brain. contains more neurons than the rest of the brain combined and a huge number of synapses. Contributes to many aspects of brain functioning, especially anything that relates to aim or timing.

30. Describe basal ganglia

pg. 241

basal ganglia: applies collectively to a group of large subcortical structures in the forebrain.

-various authorities differ in which structures they include apart of the basal ganglia, but everyone includes at least the:

-caudate nucleus, putamen, and the globus pallidus.

-Basal ganglia important for spontaneous, self-initiated behaviors.

-critical for learning new habits.

31. Understand the readiness potential and conscious will

pg.245

motor cortex produces an activity called readiness potential. Before any voluntary movement, and on the average, the readiness potential begins at least 500 ms before the movement.

The brain activity responsible for the movement apparently before the person's conscious decision.

32. Know how Parkinson's disease develops

Develops by degeneration of dopamine

pg.249

gradual loss of dopamine-releasing axons from the substantia nigra to the stratium. Primary results are rigidity, muscle tremors, slow movements, and difficulty initiating voluntary activity. The movement problems include difficulty inhibiting inappropriate movement.

33. Describe the function of the PPA

34. Know the purpose of CSF

CSF: provides nutrients to the brain.

35. Describe phrenology

phrenology: use to A process of relating skull anatomy to behavior. study how the brain functions. looked at bumps on people head.