Assignment 4: An Introduction to Functional Neuroanatomy.

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1 Assignment 4: An Introduction to Functional Neuroanatomy. Neurons are organized into functional regions of the brain that work together to produce complete behaviors. This process is called distributive processing. In this assignment we cannot possibly study the entire brain. Instead will are going to focus on a dozen or so structures that were selected to provide you with enough background to understand how the brain works so that you would have the foundation to study and understand any neurological or psychological disorder. As we go through this assignment record on Figure 1 the location of each of the structures covered. Be sure to pay attention to nearby structures as well. For each structure that you add to the diagram make sure that you understand the role of that structure in behavior. Note: for this course you are only responsible for Figure 1 on the unit exam. However, there are several structures that we will discuss that are not visible on the diagram. For those structures you only need to know their behavioral functions and that they are not found at midline. The cases for this assignment are found by selecting the Assignments Menu in your book and then choose Assignment 4. Follow the onscreen instructions to access the images and video for the assignment. Preparation. Read chapter 4 and complete the reading quiz on D2L before you complete this assignment. You will need to have your book open. Your book will directly connect you to a web site to access video cases for this assignment so you must have access to an internet connection but all other browsers and Skype should be off while you complete the assignment. Course Note: In the traditional lecture we use two 50-minute lectures to work through these concepts. Allow 100 minutes to complete this assignment. Don t forget that you can use the Live Online Chat or Discussion Board for this unit to ask questions about the assignment. GRADING: This assignment is worth 40 points. When you have completed the exercises in this handout you will be required to enter your answers in D2L. You will be allowed to complete the assignment up to two times. D2L will grade your assignment and you will be able to view all incorrect answers under submissions. Please keep in mind that once you start an assignment on D2L you must finish it within the time limit. So do not proceed to D2L until you have completed all parts of the handout first.

2 Figure 1. Label the structures covered in this assignment. Behavioral Notes:

3 Select the Assignments Menu in your book and then choose Assignment 4. Record your observations on this handout. You will need them to complete the assignment on D2L. Spinal Cord Most of the connections between the brain and peripheral nervous system or PNS enter the central nervous system (CNS) through the spinal cord. These connections run two ways. Information is carried from the PNS to the brain (in pathways called afferent or ascending pathways) or from the brain to the PNS through pathways of neurons called efferents (or descending pathways). Click on the spinal cord section. The spinal cord is connected to the brain at the medulla. Watch the video linked to the spinal cord MRI and record the functions of the spinal cord on your diagram. 1.) The sympathetic nervous system is part of the? a.) nervous system b.) peripheral nervous system c.) autonomic nervous system. 2.) The ascending nervous system carries information about tissue damage to that the brain that is sent from a.) sensory neurons b.) special sensory neurons called nociceptors c.) motor neurons. 3.) Movement of the limbs is controlled by (select all (if any) that apply) a.) the brain through the descending motor pathways b.) directly by the spinal cord through by using the reflex arc c.) somatic nervous system d.) autonomic nervous system

4 Medulla Click on the medulla section. The medulla lies between the spinal cord and pons. Watch the video linked to the medulla MRI and record the functions of the medulla on your diagram. 4.) Why would a patient likely die if the medulla was damaged? a.) the heart would stop b.) breathing would stop c.) the person would be unable to control the PNS would contribute to death following medullary damage Pons Click on the pons section. The pons lies superior to the medulla and ventral to the cerebellum. Watch the video linked to the Pons MRI and record the functions of the pons on your diagram. 5.) Which of the following functions are shared by both the pons and medulla? a.) contains the somas of cranial nerves that control heart rate b.) contains ascending and descending motor pathways c.) contains areas that control sleep and arousal are processed by both areas 6.) If your dorsolateral pons was damaged you would? a.) be unable to fall asleep. b.) act out your dreams that occur during REM sleep c.) sleep walk e.) none of these 7.) Patients with REM without atonia (also called REM sleep disorder)? a.) are unable to dream b.) stop breathing during REM sleep c.) sleep walk e.) none of these

5 Cerebellum Click on the cerebellum section. The cerebellum is superior to (just above) the pons. Watch the video linked to the cerebellum MRI and record the functions of the cerebellum on your diagram. 8.) Based on the first case with mild cerebellum damage, the cerebellum controls? a.) balance b.) force and range of movements c.) adjusts movements as they occur are functions of the cerebellum 9.) Some patients with neurological and psychological disorders resist treatment and try to deny that they have a problem. The older male first case had suddenly become clumsy (spilling coffee and falling down) and his concerned wife forced him to come in. How did he try to hide his inability to touch the tip of his nose with his finger? a.) he refused to do the test b.) when he missed he pretended that he intended to scratch his face c.) he distracted the doctor until he could get the finger to the tip of his nose. IMPORTANT: DO NOT PROCEED TO THE NEXT PAGE UNLESS YOU HAVE VIEWED THE ENTIRE CEREBELLUM VIDEO.

6 Plasticity following Brain Damage Our next discussion will involve the second cerebellum case. You should have predicted that she would have had impaired balance, impaired skill learning and should have shown a more severe cerebellar action tremor compared to the first cerebellar case since her brain damage was clearly more extensive. If you did, you obtained the correct hypotheses. You should have been very surprised that this was not at all the case. She had intact balance and she seemed to learn this task very quickly (0 errors on the first and last trial). So before we go any further lets just make sure that her behavior was not really impaired. Perhaps this test is easy and we just couldn t tell that she was impaired. From the first unit, you know that we need a control group to be able to fully evaluate her behavior and test your hypothesis. Since we need a control group, you are elected to be that control group. Instructions: First, make sure the volume on your computer is turned up to 100% and no other programs other than your book are running. You are now going to complete a computerized version of the mirror tracing test to serve as the control for this study. Select Skill Learning from the Experiments menu of your book. Follow the onscreen instructions. Complete five trials but wait at least two minutes between each trial. However, you must complete all five trials within 20 minutes. If you need a stopwatch to time the waiting period select Stopwatch under the Experiments menu. Enter your data into Table 1 below. Remember your goal is to trace the image as fast as you can but with as few errors as possible. Warning. If you don t completely trace the star the software will not shut off. You will have to go around again. The software works fine. If you post a question saying it would not shut off, then I know you were trying to cheat. Table 1. Data Table for Cerebellum Study Trial My Errors My Total Time (time to complete the trial: 4 th column from the test software Her Errors Her time to complete the Trial (s)

7 10.) If we compare her motor skill learning ability to yours and compare her other cerebellum dependent behaviors to the first case we would conclude that? a.) large lesions of the cerebellum in one hemisphere produce bigger behavioral deficits than small ones in both hemispheres. b.) the cerebellum is involved in emotional processing. c.) the brain is not involved in controlling behavior. d.) damage to the cerebellum causes cerebellar action tremors in all cases. We need to add some details. Our first case was in his 70 s when his cerebellar stroke occurred. Our second case had a brain tumor that was present from late gestation until its removal at age 16 years (the behavior you saw was recorded at 22 years). The pattern of recovery (called plasticity) in these two cases is typical. If brain damage occurs after neurons have fully developed and the behavior has been learned (by age two for motor function), then the brain is unlikely to recover. But if damage occurs at an early age then other areas of the brain can sometimes do the job of the missing region. In our second case, she never had two intact cerebellar lobes. She only had one intact lobe. You have two lobes of the cerebellum that processes 80% of motor function ipsilaterally (same side). Assuming you are right handed, when you learned the mirrortracing task you learned it using your left cerebellum. Once you learned it, the memory for the skill was transferred from your left cerebellum to a memory store in your right cerebellum (this started to happen in trial 3 or 4 that is why you probably got worse on one of these trials). However, she only has one intact hemisphere the left cerebellum. So she learns and remembers with the same cerebellar hemisphere (she skipped a step and thus learns faster). In our formal study we tested 100 controls that were matched for age, gender and race. She learned faster and with fewer errors (control average was 16 errors for first trial and 4 errors for last trial) than all of our 98 right-handed subjects (like her), and only two were as good or slightly better and both of these were left-handed. 11.) Given this new information. Reevaluate her behavior relative to yours and that of the first case. Select all that apply. a.) the age at which brain damage occurs can be more important than the size of the lesion in predicting the development of long-term behavioral deficits following brain damage. b.) one cerebellar lobe can do the job of two if the brain damage occurs early enough. c.) plasticity following brain damage is age dependent. d.) damage to the cerebellum causes cerebellar action tremors in all cases. e.) young brains are more resistant to brain damage than adult brains.

8 12.) What kind of research design did you use in this demonstration? a.) correlational b.) experimental c.) case study d.) observational research Note: the computerized version of the mirror trace test is a little easier than the standard version. So your performance was probably a little better than the data for in the control group in our formal study but you were most likely still much worse than she was. Midbrain or Mesencaphalon Click on the midbrain section. The midbrain or mesencephalon lies (as its name implies) in the middle of the brain. Watch the video linked to the midbrain MRI and record the functions of the midbrain on your diagram. 13.) Endorophins released from the hypothalamus during stress produce analgesia by targeting the? a.) basal ganglia b.) colliculi c.) periaqueductal grey d.) substantia nigra 14.) Parkinson s disease occurs when 50% or more neurons die in the? a.) basal ganglia b.) colliculi c.) periaqueductal grey d.) substantia nigra 15.) The loss of dopamine in the basal ganglia resulted in in the case of early Parkinson s disease shown in the video? Select all that apply. a.) a slow shuffling gait b.) a loss of the blink reflex c.) impaired control of facial muscles (lack of smiling and facial expression) d.) a resting tremor e.) difficulty getting up from a chair f.) impaired balance Course Note: in the next unit we will discuss the causes and treatment of Parkinson s disease. At this point in the course you only need to know the symptoms and damage caused by the disease in

9 order to understand the role of dopamine in the normal functioning of the substantia nigra and basal ganglia. Diencephalon: Thalamus and Hypothalamus Click on the thalamus section. The thalamus is part of the diencephalon and lies above the hypothalamus. Watch the video linked to the thalamus MRI and record the functions of the thalamus on your diagram. 16.) Psilocybin and LSD both produce hallucinations by acting as in the thalamus causing overload of the frontal lobe? a.) serotonin agonists b.) dopamine agonists c.) serotonin antagonists d.) dopamine antagonists 17.) The use of LSD by visionary artists such as Alex Grey shows that? a.) serotonergic psychedelics are safe and effective tools for unlocking the secrets of the mind (brain) b.) serotonergic psychedelics produce intense hallucinations c.) serotonergic psychedelics are highly addictive d.) serotonergic psychedelics produce analgesia Click on the hypothalamus section. The hypothalamus is part of the diencephalon and lies above the pituitary and below the thalamus. Watch the video linked to the hypothalamus MRI and record the functions of the hypthalamus on your diagram. 18.) Progesterone is hormone involved in reproduction but it also controls some aspects of human aggression because a.) there are large numbers of progesterone receptors in the aggression areas of the hypothalamus b.) the hypothalamus controls the production and release of progesterone by the anterior pituitary c.) it was shown that progesterone injections reduced aggression in Sandy 19.) The hypothalamus? a.) controls emotion b.) controls the endocrine system c.) controls the autonomic nervous system

10 Click on the basal ganglia section. The basal ganglia are part of the telencephalon and is not shown in Figure 1. Watch the video linked to the basal ganglia MRI and then answer the question below. Earlier we discussed the importance of the role of the basal ganglia in controlling voluntary behavior (see the section on the substantia nigra). The basal ganglia also play an important role in a specific type of voluntary behaviors related to mate bonding and parent-child bonding and social attachment. 20.) Individuals and species that are missing oxytocin or oxytocin receptors in the basal ganglia a.) form very strong loving bonds with their offspring b.) tend to be monogamous and mate for life c.) do not form strong social bonds with their mates or offspring Click on the limbic system section. The limbic system is part of the telencephalon and is not shown in Figure 1. Click on the MRI of the limbic system. There is no video in this unit for this topic. These structures will be important for understanding several diseases that will be covered in the next unit. For now know their location and general function as described in the MRI and then answer the question below. 21.) Match the limbic system structure to its role in behavior. amygdala hippocampus a.) form new memories for the material in this course b.) form and remember memories for emotional events c.) processes emotional responses and events The cortex is part of the telencephalon and controls the most complex aspects of behavior. To illustrate how the cortex controls behavior click on the MRI of the cortex. Watch the video and then answer the questions below.

11 22.) What is your diagnosis for John? a.) Broca s aphasia b.) Conduction aphasia c.) Wernicke s aphasia 23.) What is your diagnosis for Martin? a.) Broca s aphasia b.) Conduction aphasia c.) Wernicke s aphasia 24.) Insults to the brain rarely damage only one region. Go back and review John again. But consider the following. The limbic cortex which determines whether you will get emotional about something lies adjacent to the language center damaged in John as does the motor cortex and motor planning areas. Keep in mind that motor control is contralaterally processed and that John is RIGHT-handed. What other issues did you notice with John? Select all that apply. a.) He has a little trouble regulating is emotional response when his answer was corrected for more detail. b.) He has limited use of his right hand. c.) He showed a slight cerebellar action tremor. d.) He had a mild resting tremor. You are now ready to complete the online questions for this assignment. Remember you only are allowed up to two attempts. So if you do not feel ready go back and do the assignment over. It is your last score that counts. You will need this handout. Close your book and use the Respondus Browser to enter your answers in D2L (Assignment 4).