COGS 107B. Week 7 Section IA: Ryan Szeto OH: Wednesday CSB Kitchen

Transcription

1 COGS 107B Week 7 Section IA: Ryan Szeto OH: Wednesday CSB Kitchen

2 MT2: Tomorrow

3 Question 1 NE: Locus coeruleus HA: Posterior hypothalamus ACh: Two pockets- located in pons and basal forebrain DA: Two pockets- located in ventral tegmental area and substantia nigra 5-HT: Located in multiple raphe nuclei (in brainstem)

4 Question 2 Depth perception: Motion parallax Texture gradient Occlusion Retinal disparity Frame of reference: Egocentric Allocentric Object-centered Route-centered

5 Question 3 Head direction cells and grid cells form universal maps. That is, the maps are always rigid, but just rotate based on changing environmental cues. On the other hand, place cells are non universal. There is a unique map for every environment. The relationship between preferred firing directions of two head direction cells (or grid cells) are always fixed. If neuron A s firing direction rotates, neuron B s firing direction will rotate at the same magnitude, always keeping the same angle relative to A. But rotating the environment will rotate the same place cell map for that environment.

6 Question 4 The axons of granule cells are called parallel fibers, which perpendicularly intersect with the dendrites of purkinje cells in the cerebellum. The parallel fibers synapse multiple times on each purkinje cell s dendritic tree.

7 Question 5 The inferior olive sends axons, known as climbing fibers, up to the cerebellum along proximal branches of dendritic purkinje tree, and makes a bunch of excitatory synapses which show high rates of firing (at the purkinje cell) when the expectation of your action doesn t match up to the action itself. Professor Nitz referred to this as a learning moment.

8 Question 6 Metabotropic receptors modulate voltage gated ion channels.

9 Question 7 The CA3 region shows 4% connectivity with itself, meaning that each neuron in CA3 is connected to approximately this percentage of all neurons in CA3. On the other hand, CA1 displays 1% connectivity with itself.

10 Question 8 Circle the correct answer. (HA / 5-HT / DA) neurons show higher spiking activity when the actual reward presented by a stimulus is greater than the expected reward.

11 Question 9 One proposed function of sleep is homeostasis, where a physiological system strives to maintain internal stability.

12 Question 10 The local field potential (LFP) reflects temporal coherence in synaptic activity.

13 Question 11 The theta rhythm is the most prominent brain rhythm of any mammal. Particularly, rats show this rhythm when they conduct spatial navigation tasks.

14 Question 12 The fourier transform is the tool researchers use to decompose a recorded signal into its components.

15 Question 13 REM Behavior Disorder is a condition in which individuals display malfunctioning trunk atonia. These individuals will move during sleep and act out their dreams. This is not to be confused with sleepwalking, which occurs during stage 3/4 sleep.

16 Question 14 Updated 2/20 after section to include more on orexin neurons! The condition of narcolepsy, where some symptoms include abnormal REM sleep and sleep paralysis, usually comes with the observation that orexin neurons (which are known for promoting wakefulness) are absent in the brain. An accompanying symptom, known as cataplexy, occurs when REM muscle atonia suddenly turns on during the waking state when the individual experiences strong emotions. This can result in a total body collapse (the eyes, fingers, and voice can usually still work). Orexin neurons promote neuromodulator activity. Neuromodulatory neurons fire less during REM. So, since neuromodulatory neurons are closer to sleep activity during wake state for narcoleptics, they tend to be sleepy people.

17 Question 15 Circle the correct answer. In humans, one sleep cycle occurs every (30 / 60 / 90) minutes. Researchers discovered that animals with (smaller / larger) brain sizes have longer sleep cycles.

18 Question 16 Circle the correct answers. The (direct / indirect) pathway goes through the GPe, which will then create relative (inhibition / excitation) on the GPi. As a result, the thalamus will become more (inhibited / excited) and decrease excitation of the cortex.

19 Question 17 Circle the correct answers. Spiny GABA-ergic neurons in the direct pathway have (type 1 / type 2) DA receptors. DA receptors are (ionotropic / metabotropic). The type of DA receptors found in the direct pathway will (amplify / weaken) incoming EPSP signals.

20 Question 18 (True / False) Each cerebellar nucleus contains a tonotopic map. Each cerebellar nucleus contains a homunculus.

21 Question 19

22 Questions? Good luck!