Psychology Past Paper PDF

Please do not ever post online/social media and do not ever distribute. All rights reserved. Thanks! CHAPTER 2 METHODS I – Introduction: Definition: Psych is a science. Study of how we think, feel, and behave. Sco...

Please do not ever post online/social media and do not ever distribute. All rights reserved. Thanks! CHAPTER 2 METHODS I – Introduction: Definition: Psych is a science. Study of how we think, feel, and behave. Scope: Huge since every aspect of human life is psych. A - Why do we need science? Intuition: When it comes to understanding the natural world, intuition is not the way to go. Can be misleading. Common sense: Common sense is not so common. What’s common sense to me is not common sense to you. Even when common sense produces good judgement, we cannot use it to understand the natural world because it does not introduce new knowledge. Overconfidence: Humans tend to be overconfident. B- How Do We Know?: Rationalism: We cannot trust our senses and experiences. We must use pure logic, reason, and critical thinking. Empiricism: The best way to know is to use our senses. (Observations) Kant: According to Kant, we need both empiricism and rationalism together. C- The Scientific Method: 1. Identify the problem 2. Gather information 3. Develop a hypothesis (See below) 4. Design and conduct experiment (or other type of studies). 5. Analyze the data and draw conclusion 6. Restart the process Develop a hypothesis: Definition: Tentative statement about the relationship between one or more variables. Must be falsifiable: Must be able to test and falsify the hypothesis. Replication: We must replicate our studies with different sets of subjects. Our confidence grows if we repeat and get similar results. Evolution: Science is constantly evolving. Science is self-correcting. II – Types of Research Methods (3) A- Descriptive Research: A.1 Purpose: It allows: It allows us to systemically and objectively observe and describe observations. It allows us to answer: What When Where How However, it does not: Answer the “Why”. Cannot draw conclusions about cause and effect. A.2 Case Study: Definition: Study in depth of either one person or a small group of people. Advantages: Keep a record: Keep a record of rare events and cases that otherwise would be lost. 1st step: Excellent first step when something is very complex, or we don’t know much about it. Most: Most in depth research one can do Capture: When we do a case study it may allow us to capture a glimpse of human nature and the human condition. Disadvantages: Researcher bias: No matter how hard researchers try to be objective they still may be influenced by their own theories, beliefs, and expectations. They may end up hearing what they want to hear and seeing what they want to see. Cannot: CANNOT generalize from a case study because the sample is so small. A.3 Survey: Definition: Researchers asking a large sample of people questions that they would like the answer to. It is impossible to survey every single person in a population. The solution is to extract a sample from the population. Representative sample: We need to make sure the characteristics of our sample closely reflect the characteristics of our population. Why? We must have it because we use that sample to generalize to the population. How? Researchers use random sampling in order to obtain a random sample. Random sampling: Every single person in the population of interest has an equal chance to be in the survey. Chance, only chance and nothing but chance determines who ends up in the sample. Simple random sample: Go into the population of interest and extract a sample using random sampling Stratified random sample: We take the population we are interested in, and we break it down into the different groups we are interested in. Then we go into every one of those groups and extract a sample from them. Advantages: Cheap: Very cheap Easy to: Very easy to administer Includes: We can include people that aren’t usually included in research. Ex. Illiterate people, homebound people, etc. Sometimes it is the only way: Sometimes it is the only way to know something. Disadvantages: Truth: Just because you ask something, it doesn’t mean you’ll get the truth. Easily: The answers we get can be easily influenced by how we word a question (Word influence). The results we get can be easily affected by the characteristics of the person asking the question. To help you out a little bit and save you some time, I created the following notes for you: Here is some more useful information: As I have mentioned in the lecture, just because the researchers ask a question, it does not mean they are going to get the correct, accurate, or honest answer. Response bias can be a major problem in survey research. It is a general term that refers to a number of factors that could lead subjects to answer inaccurately. Here are a couple of examples: Acquiescence bias: tendency for a subject to agree with whatever the researcher is asking. No variety in the answers. Agree or yes, dominates their answers regardless of what the question is about. Social desirability bias: as mentioned in the lecture, sometimes subjects may not give an honest answer because they want to be perceived in a positive light. They want to be liked. As a result, they provide the politically correct and socially desirable answer and they hide their true opinion, attitude and behaviours. For example, they may be prejudiced against immigrants but in the survey they may indicate that they support policies aiming at increasing the number of immigrants accepted in the country.  Your book mentions a couple of other biases: Volunteer bias: that would be a problem if researchers do not use random sampling and rely instead on volunteers to answer their surveys. These volunteers may not be representative of the population of interest. The mere fact that they are volunteering while others are refraining to do so is a hint to a potential difference. Illusory superiority (part of what is known as the self-serving bias) is the tendency for most people to perceive themselves as better than average. Most people tend to perceive themselves as sexier, smarter, kinder etc., than average. Mathematically, this is total nonsense. How could MOST be better than the average??? :) Are you better than average? :) A.4 Naturalistic Observation Definition: The research leave their labs and they do their research in the real world. A fundamental rule: The researcher must not interfere in any way, shape or form. They are just to observe. Advantages: Real: It does not get more real than this. We move away from the artificiality of the lab. Sometimes this is the only way: Sometimes this is the only way to get the information we need. Discovery: By going to the real world to do research, we may discover things that we may never discover in the lab. Disadvantages: Researcher bias: Researcher bias same as before. The presence: Even though researchers do not interfere, still the mere presence of the researcher can influence an effect and change the observed behaviours. Solution is that researcher must blend in. A.5 Participant observation: Participant observation is a research method in which a researcher becomes part of the group under investigation. Sometimes this is the only way to gain access to a group. B- Correlational Research: Observe, describe, and make predictions. Purpose: Allows us to find out if there is a systematic and reliable relationship between two or more variables. 3 major questions: Q1. Do they covary? Is there a relationship? If one variable changes, does the other change as well. If yes, they covary. Q2. In what direction? Positive correlation: The two variables change in the same direction. Negative correlation: The two variables change in opposite direction. If one goes up, other goes down and vice versa. Q3. How strong is the relationship? To what extent? Correlation coefficient: r, allows us to answer all 3 questions. Value of r ranges between, -1 and +1. (-) does not mean weak it means negative correlation. (+) does not mean strong, it means postivie correlation. (1) mean perfect correlation. (0) means there is no correlation. Advantages: Excellent first step: Before an experiment is done, one starts by doing a correlational study. If relationship is found, an experiment can be done. The only option: Sometimes it is our only option. Describe and predict: If we know information about one of the variables, we can make a prediction about the other. Take: Once we know there is a correlation between two variables, we can start taking precautions and preventive measures. Disadvantages: CANNOT CANNOT: CANNOT infer causality. You CANNOT say there is a cause-and-effect relationship. C. Experimental Research: C.1 Introduction: Experimental research allows us to observe, describe, predict and explain. It is the only: Type of research that allows us to talk about cause-and-effect relationships. Can be done in the lab and real world. Why? 1) Researcher manipulates independent variable of interest. 2) Researcher controls all other independent variables that could interfere with his results. Independent variable (IV): Variable that causes change in another variable. Either manipulated or controlled. Dependent variable (DV): Variable that is being changed, influenced, affected by the independent variable. Researcher measures this. Can be done: In the lab Field experiment: Done in the real world. Here researcher. Can manipulate and control variables C.2 Manipulate the IV: Create two levels of the IV of interest. = create two groups. One group will be exposed to the IV (experimental group) and one group will not be exposed to IV(Control group). Ex. Milk increases bone density. 1 group of females drink milk, 1 group doesn’t drink milk. C.3 Control All Other IVs: MUST! Control all other independent variables that he is not studying so that they do not affect the dependant variable. Must control both known and unknown independent variables. Confounding variables: Independent variables that aren’t the subject of interest but could affect results. They must be controlled. Why? The researcher won’t know which variable caused the change in the dependant variable. His results would be useless. Known IVs: Independent variables that we know from past knowledge, experience, etc. that they do influence the dependant variable of interest. Unknown IVs: Random assignment: Every single subject in the study, has a chance of being in the control group or experimental group. Chance, only chance, nothing but chance will determine which subject will be in the control group and who’s going to be in the experimental group. Placebo effect: We must control for the placebo effect. Inert: Placebo is an inert substance or value that has no effect. III – Making Sense Of The Data (Section 2.7 in the book) Earn a point assignment: On your own, study subsections: 2.7.1 and 2.7.2 of the book. There is nothing to submit. Master this information and guaranteed there will be questions on the first midterm from those 2 subsections. You do not need to confirm this with me. The information is accurate. Subsection: 2.7.3 of the book: is not included on any of the exams, including the final. You do not need to confirm this with me :) It is not part of the course. Happy Learning :) CHAPTER 3 Biology & Neuroscience I to VI I - The Nervous System: It consists: NS CNS PNS Brain and spinal cord All nerves that are not part of the brain and spinal cord. The 2 divisions: Central and Peripheral Nervous Systems. Even simple movements require both. Your NS is: Distinct and unique. Receives: Receives info from environment and internal body. Analyzes: Organize analyze and integrate the information. Uses this information to: Use info in order to send out messages to muscles, glands, etc. in order to produce behaviours. Along the way: Nervous system creates consciousness and awareness (see chapter 6). The question: Why do we learn about the nervous system in psychology? Anything psychological is biological and physiological. II. Cells of the NS: A. Neurons: Basic unit : Basic unit of communication in the nervous system. In a nutshell: The communication: It is an electrochemical process. When: A neuron decides to communicate with another neuron, it fires an action potential (AP). Action potential/neural impulse/electrical impulse: they all mean the same thing Ultimately: The action potential is going to lead to the release of NTM. Neurotransmitters: Chemicals that neurons use to send out messages to other neurons. Neurons come: In a variety of shapes and sizes. Basic structure: Neurons have roughly the same structure. Cell body soma: Contains the nucleus and the DNA. Manufactures everything the neuron needs to survive and thrive. Dendrites: Two main functions: a) Receive messages from other neurons. b) They increase the SA of the soma without taking up much space. Axon: When the neuron fires and produces an AP, it is the axon that will carry it. AP travels all the way down the axon. Axon branches/ Axon terminals: Axon branches off into axon terminals. Terminal buttons: Little nubs at the ends of axon branches. They release the NTM’s. Myelin sheath: Some axons in the NS are covered in a myelin sheath. White fatty substance that traps around some axons. Provides insulation Speeds up transmission of info. Synapse: This is where neurons meet to communicate. Synaptic cleft/gap: Tiny gap between two neurons at the synapse. Presynaptic neuron is the neuron that sends out messages. Postsynaptic neuron is the neuron that receives messages. B. Glial Cells (Glia): Another type of cell found in the NS. There are billions of them. Nannies of the neurons because they help neurons: develop nutrition insulation protection clean after them remove dead neurons More than just nannies: Seem to be involved in complex functions including cognitive ones such as learning, attention, intelligence, and creativity. They seem to be also linked with brain diseases. There are different types of glia cells carrying out a variety of different functions. Below are some examples: Oligodendrocytes and Schwan cells are both involved in the production, laying down, and repair of the myelin sheath. Oligodendrocytes do so in the CNS while Schwan cells do so in the nerves outside of the brain and spinal cord. Microglia: Immune function. Play a role in learning and memory: degeneration linked with Alzheimer’s disease. Astrocytes: Immune function. Linked to neurodegenerative diseases. III. Communication: A & B: A. Communication within a neuron: 80%:Water Intracellular fluid: Inside the neuron. Extracellular fluid: Outside the neuron. Dissolved chemicals, such as: Na+ Sodium I. Cl - Chloride I. K+ Potassium I. These ions: They are found inside and outside the neuron in different concentrations. Neuron at rest: Neuron is not firing, communicating, not producing an AP. More negative ions inside the neuron. (Inside = negatively charged) More positive ions outside the neuron. (Outside = positively charged) -70mV Polarized Even at rest: The neuron receives messages from other neurons. 2 types of messages: Inhibitory: Instruct the neuron Not to fire not to communicate. These messages are going to: The inside is going to become more negative than at rest. e.g., from -70 mv to -77 mv As a result, the neuron is: Less likely to fire. The membrane is said to be: Hyperpolarized. Excitatory: Instruct the neuron to Fire, communicate, produce an action potential. These messages are going to: Change the concentration of ions. less negative: Inside of neuron will be less negative than at rest. e.g., from - 70mV to - 63mV As a result, the neuron is more: Likely to fire. The membrane is said to be: Depolarized. When?: When electric charge inside the neuron is about -50 mV (threshold of excitation). Now that you have a conceptual understanding of the action potential process. Let us plug in some chemicals. Please note, there is more to the process than covered here. It is beyond an INTRO PSY to cover all of it. You will learn more as you move up the years. Hello Everyone! Please make sure to have studied and mastered the communication within neurons before studying this section. Study this section one baby step at a time and slowly. And go over it few times until the information becomes more familiar. Let me introduce you to the nodes of Ranvier. Please follow the arrows. They are gaps in the myelin sheath that covers the axons. (gentle reminder: Not all axons are covered with Myelin) Why are they there? Do you have doors and windows in your walls? Clearly, the answer is yes. The nodes are the “walls and windows of the axons. Through them, ions can get in and out of the neuron. Technical term: channels. The ions do not move in and out as they please. There are “rules” that govern their movements. We are going to take a look at a couple of those “rules”. You will learn more in the second and third year. When a neuron receives inhibitory messages, Chloride (Cl-) channels open.  What happens when they open? Some chloride ions move inside the neuron. (Influx) When they move in, that increases the number of negative ions inside the neuron. As a result, the inside of the neuron becomes more negative (more negatively charged) The membrane is said to be hyperpolarized and the neuron is less likely to fire. (again there is more to the process but for the purposes of this course that is all you need to know) When a neuron receives excitatory messages, the sodium channels open. What happens when they open? Some sodium ions move inside the neuron. (Influx) This increases the number of positive ions found inside the neuron. As a result, the inside of the neuron becomes less negative (less negatively charged) As you know this means that the membrane is depolarized and the neuron is more likely to fire. If enough sodium ions enter the neuron for the electrical charge inside the neuron to reach -50mv (threshold of excitation> explained in the lecture) the neuron will fire. Once the neuron has fired, it needs to go back to its resting potential before it can fire again when prompted. How does the neuron return to the resting potential.? After (key word) the sodium channels have opened and sodium ions had entered the cell, potassium (K+) channels open. What happens when potassium channel open? Potassium ions start leaving the neuron (Efflux) Keep it simple. That is all you need to know for now. By potassium ions leaving the neuron, that means there are less positive ions inside the neuron. The inside of the cell becomes less positive. Ultimately, the electrical charge reaches -70mv and the neuron is polarized again. The neuron is at its resting potential. Right before the neuron reaches its resting potential, it goes through a refractory period. During this period the neuron will not fire when stimulated. The membrane is hyperpolarized (more negative than -70mv) due to the migration of a high number of potassium ions out of the cell. You might be wondering what happens to the sodium ions that entered the cell, or to the potassium ions that left the cell? Ultimately, sodium ions will be pumped out and potassium ions will be pumped back in. Again, the processes are more complex but that is sufficient for our purposes. B Communication between neurons: The presynaptic neuron fires: Action potential travels/propagates all the way down the axon until it reaches  Terminal buttons (contain synaptic vesicles) Synaptic vesicles attach to membrane and bust open releasing (Little bags containing NTM) Neurotransmitters into synaptic gap. NTM crosses gap and Bind to receptor sites The neurotransmitter must: Attach to its own receptor site otherwise the message will not be delivered. Each: Has its own receptor site. Fate of : Reuptake: The NTM detaches from receptor site and then it goes back home. It is reabsorbed into the presynaptic neuron. Recycled for future use. Degradation: Detaches from receptor site. Enzyme then comes and then degrades it. Breaks it down so it cannot deliver the message again. Why? If there is no degradation or reuptake, the NTM will deliver the same message over and over again. Causes NS to be overexcited or overinhibited. C. Neurotransmitters (NTM): Chemicals produced by the brain. Brain uses them to send messages to neurons. Some deliver excitatory messages only. Example: Acetylcholine, Glutamate Some deliver inhibitory messages only. Example: GABA Some deliver both types of messages. Examples: Dopamine, Serotonin, Norepinephrine, Enkaphalins/Endorphins. Healthy levels: Are an absolute must for us to function well physically and mentally. Dopamine: Major NTM with a variety of functions. Healthy levels: Make us happy and in good mood, motivated and pursue our goals, our motor function tends to be healthy, and we derive pleasure from life and its activities. When levels are low: We are depressed, we are not motivated, we could have motor problems, associated with Parkinson’s disease, and little to no pleasure from life. Dopamine abnormalities: Associated with schizophrenia. Study table 3.1 Book. You do not need to memorize the “Associated drugs”. C. Drugs & the brain: Synapse: Drugs produce their effect at the level of the synapse. Interfere with communications between neurons. Interfere with activity of NTM. Either enhance activity, or reduce it, or block it altogether. Drugs: Agonists: They increase enhance the activity of NTM. Ex. Increase release of NTM. Some agonists mimic the NTM. Take over the receptor site and they are going to deliver a message to the neuron. Antagonists: Drugs that decrease/ reduce activity of a NTM or block it altogether. Can block it by attaching to the receptor site and blocking it. By blocking it they stop the NTM from attaching and delivering its message. Partial agonists and partial antagonists: Same thing but lesser effect (less powerful). Competitive (direct): Some drugs are going to compete directly against the NTM for the same receptor site. The agonist will take it over and deliver a message. The antagonist will take it over and block it. Antagonist does not deliver messages. Non-competitive (indirect): Do not directly compete against the NTM for the same receptor site. They go find themselves different receptor site and they attach to it. From that receptor site they interfere with the activity of the NTM either enhancing it or reducing it.  PLEASE DO NOT POST ONLINE NOT NOW, NOT EVER Gentle reminder: The notes you take in my classroom, the documents I give you are my intellectual property. For this reason, you can not post them online, nor can you distribute them. Thank you :) *** Chapter 3: Biology & Neuroscience (I to VI) LECT 3 III. The Brain: A. Introduction: *None of the information in this introduction will be on the exam. B. Tools of Discovery: (Section 3.7 in the book) Please read the following very carefully. When it comes to this section: From the book study Table 3.2 PLUS from the main text study the information about the EEG. In addition, study any information that is mentioned in the main text about the different technologies listed in Table 3.2. Everything else in this section: Just read and enjoy; You do not need to study. You do not need to confirm this with me. The information is accurate and very clear. You do not need to study anything beyond the EEG; CT scan; MRI; fMRI; DTI; PET/SPECT scan for the midterm. You will be provided with specific instructions for the final exam. This is Table 3.2 (book) make sure to also study the main text: Method What Does It Do? Advantages Disadvantages Examples of Use CT Scan Uses x-rays that Fast, cheap, Radiation exposure. Detect changes in (Computerized pass through the and non- structure due to Tomography) body, and can invasive Does not allow us to disease generate images see the brain in of “slices” of the action (ex. a CT scan body doesn’t allow us to see which areas of the brain are more active when we’re listening to music; CT scans only shows us the structure of the brain (i.e. if there is a tumor, if it is shrunken, etc.), but not the function.) MRI (Magnetic Uses magnetic Non-invasive, Really expensive, Detect changes in Resonance fields to image great precision, cannot have structure due to Imaging) alignments of no radiation biomedical devices disease hydrogen ions or metal in patients. (different tissues have different It does not allow us amounts of to see the brain in water) action/the functioning of the brain. fMRI (functional Uses magnetic Non-invasive, Cardiovascular Can measure MRI) fields to image no radiation, disease or activation during a alignments of no injections or compromised task or following hydrogen ions ingestions function can make stimulation (different tissues measurements have different unreliable; delay amounts of between stimulus water) and output Allows us to see the brain in action DTI (Diffusion Tracks and Non-invasive, The interpretation Study white matter Tensor Imaging) images water no radiation, can be difficult in degeneration in movement along no injections or tracts that have disease neural pathways, ingestions different kinds of and can measure needed fibers density of neural tracts (bundles of axons) Uses MRI tech to track the nerves and pathways in our brain. Analogy: it tracks the bridges roads and the highways in our brain. Letting us know what goes where and what is connected with what. PET/SPECT Uses an ingested You can see Radiation exposure Visualize the activity (Single Photon radioactive molecular of specific Emission compound to changes in real neurotransmitters, Computed track molecular time. can measure binding Tomography) changes  It allows us to see the brain in action and to see the activity of neurotransmitt ers! C. Tour of The Brain: C.1 &C.2 C.1 Lower Brain Structures: C.1.1 to C.1.4 C.1.1 Brainstem: - It starts where the spinal cord ends. - It connects the brain to the spinal cord. - It is a relay station: all the info coming to the brain will have to go through it and all the information leaving the brain will have to go through it. - It is a crossover point. o The information coming from the left side of the body will cross over to the right side of the brain and vice versa. o The information coming from the right side of the body will cross over to the left side of the brain and vice versa. - It is the life center of the brain because it contains multiple structures that control and regulate vital functions that are essential for survival. These structures include the medulla, the pons and the RAS. o Medulla: Starts where the spinal cord ends; it is a structure that is essential for survival. If there is damage to the medulla, there could be serious trouble that may lead to a coma or even death. The medulla controls breathing, heartbeat, blood pressure, coughing and sneezing, swallowing, vomiting. (*study passage in book about the medulla and alcohol*) o Pons:  Explore and discover (book): In bullet form, list all the functions of the pons mentioned in your book. o RAS  Explore and discover (book): What is the RAS? Where is it located? What are its main functions? To what disorder is it linked? C.1.2 Cerebellum: The cerebellum controls: voluntary movements (ex. running), balance, muscle tone It is involved: , and it is involved in the learning of motor skills that become automatic. The cerebellum is 1/10th of the volume of the brain. Yet, over ½ of the brain’s neurons are in the cerebellum. The neurons in the cerebellum have 20x more connections between them than the rest of the brain. Recent research: Cerebellum is associated to higher mental processes (ex. learning, memory, reasoning, creativity, language). A healthy cerebellum seems important to healthy cognitive development (thus, cerebellum is also associated with autism). When we drink alcohol and get drunk, our cerebellum also gets drunk (this creates dizzy/wobbly movements). - Language example: Pause VS Paws > if our cerebellum was damaged, it would be hard to differentiate between both words. C.1.3 Thalamus: A relay station: The thalamus is located right on the centre of the brain, sitting on the bran stem. It is considered to be a relay station because all our senses, except our sense of smell, send our information to the thalamus, and the thalamus relays the information to upper brain areas. In addition, the thalamus receives information from upper brain areas and then it relays it to lower brain areas. It also filters: The thalamus filters the information and highlights what’s important, thus it is more than a relay station. Studies: suggest that it could be part of a system in our brain that directs our attention to potentially significant stimuli. Goosebumps anyone?? The thalamus is associated with experiencing goosebumps! C.1.4 Limbic System: The limbic system: - The limbic system consists of a number of different structures. - It is linked/associated to emotions, motivation, learning, memory. Hippocampus: The hippocampus is linked and associated with memory, particularly the formation of new conscious memories. - Linked/associated with the formation of cognitive maps (a mental map of a space/lay-out that is in your brain). - The hippocampus is vulnerable to stress. Chronic stress/stress hormones can kill neurons in the brain/hippocampus. - Alzheimer’s disease: The hippocampus is one of the first areas in the brain to be affected by this disease. Amygdala: - Is linked/associated with aggression. - Is linked/associated with the experience of emotions, particularly fear. It is also linked/associated with the perception of emotions and experiencing emotional memories. - One of the main jobs of the amygdala is to detect threats in our environment and to sound the alarm. It can detect and react to threatening stimuli in our environment even though were not aware of them. Hypothalamus: is known as the brain within the brain, because it controls/regulates a variety of functions that are essential for survival. - The hypothalamus controls drive (ex. hunger, thirst, sex > all necessary for survival) - Plays a major role in the maintenance of homeostasis, which maintains the internal balance of the body within a healthy narrow range (ex. maintaining healthy body temperature). - The hypothalamus plays an important role in the formation of social bonds by producing oxytocin (a hormone that does a variety of things, namely helping the formation, enhancement, and maintenance of emotional bonds). - It controls the endocrine system: (See later) - It controls the autonomic system: (See later)  PLEASE DO NOT POST ONLINE NOT NOW, NOT EVER Gentle reminder: The notes you take in my classroom, the documents I give you are my intellectual property. For this reason, you can not post them online nor can you distribute them. Thank you :) CHAPTER 3 Biology & Neuroscience I to VI LECT 4 C.2 Cerebral Cortex: Introduction: C.2.1to C.2.3: Introduction: Cortex is the outer layer of the brain. Because of the cortex we are highly adaptable. The cerebral cortex is the largest relative to body size, and is the most complex on the planet. 1/3: We can see 1/3 of the cortex, the rest of the cortex is hidden in grooves and valleys. 2 hemispheres: In our cortex we have two hemispheres, the left and right hemisphere. If you part them open, you see the corpus callusom. o Corpus Callusom It’s a bundle of nerve fibers. It is what the two hemispheres use in order to communicate with one another. For the rest of this introduction and for C.2.1 and C.2.2, please see handout below  HANDOUT C.2 CEREBRAL CORTEX INTRODUCTION Please add this information to what we have already discussed in class. We have two hemispheres: The left hemisphere and the right hemisphere. The left hemisphere: Receives information from the right side of the body. Controls the right side of the body. The right hemisphere: Receives information from the left side of the body. Controls the left side of the body. Each hemisphere consists of 4 lobes. SEE Fig. below They are the: Frontal 149 Parietal Temporal Occipital Each lobe consists of two areas: Primary and Association. C.2.1 PRIMARY AREAS Primary areas are found in each lobe. They are linked and associated with the processing of either motor or sensory information. The primary areas are: P. visual cortex located in the occipital lobes (processes visual information). SEE Fig. below P. auditory cortex located in the temporal lobes (processes auditory information). SEE Fig.3.28 in the book P. sensory cortex also known as P. somatosensory cortex. SEE Fig. below It is located in the parietal lobes. It arches from one ear to the next. It receives information from the skin, muscles and joints. Processes information pertaining to touch, pain, temperature etc.. The right part of the parietal cortex receives info from the left side of the body. The left part of the parietal cortex receives information from the right side of the body. Each body part is represented in the parietal cortex. Body parts adjacent to each other (example, hand and arm) are serviced by areas in the brain that are adjacent to each other. The actual size of a body part has nothing to do with the size of the area the brain devotes to this part. Check the size of the area devoted to your hand compared to that devoted to the rest of your body. Somatosensory Cortex 150 P. motor cortex located in the frontal lobes. SEE Fig. below. It arches from one ear to the next and it controls voluntary movements. The right part of the motor cortex services the left side of the body and the left part services the right part of the body. Body parts adjacent to each other (example, hand and arm) are serviced by areas in the brain that are adjacent to each other. The actual size of a body part has nothing to do with the size of the area the brain devotes to this part. Check the size of the area devoted to your hand compared to that devoted to the rest of your body in the figure above.  Primary Motor Cortex 149 C.2.2 ASSOCIATION AREAS As mentioned above each lobe has two areas: Primary and association. Association areas are found in each lobe and they are linked and associated with higher and more complex mental functioning (e.g., reasoning). The association areas are also involved in the processing of complex motor or sensory information. Below you will find examples of some of the functions that have been linked to the association areas of the cerebral cortex. Frontal Lobes (Executive function): o Attention o Planning o Decision making o Abstract thinking o Some aspects of memory o Some aspects of personality o Some aspects of language (Broca’s area language production) o Impulse control o Emotions o The last area of the brain to be myelinated and to mature. Temporal Lobes: o Some aspects of language (Wernicke’s area: understanding language) o Recognizing faces o Music o Some aspects of memory o God spot Parietal Lobes: o Nonverbal thinking (e.g. math, spatial reasoning)  o Sense of space Occipital Lobes o Processing of complex visual information Keep in mind however that: The brain’s lobes work in tandem to produce complex human behaviours & mental processes C.2.3 Brain Plasticity Not included on any of the exams. You do not need to confirm this information with me. This is just for your information. I think it is important that you know this about your brain. D. Brain laterality: Functional asymmetry: Means the same thing as Brain laterality. Our two hemispheres do have similar functions. However, it seems that each one has its own skills and its own specialties. For example, language is more linked and associated with the left hemisphere. Just because both hemispheres have similar functions, we don’t have a left or right brain, we have one single brain and the hemispheres are constantly working to produce behaviours, emotions, etc. How did we know that we had two hemispheres? 1. Clinical Observation 2. Neuro imaging techniques 3. Split brain patients Split-brain patients: These are patients who suffered from severe secures. To get rid of the secures, medical doctors cut off their corpus callosum. Corpus callosum: Bundle of nerve fibers that the hemispheres use to communicate.  Keep in mind: We have a right visual field, and left visual field (it doesn’t mean left or right eye). Any information that is flashed to the RIGHT visual field is sent to the LEFT hemisphere. Any information that is flashed to the LEFT visual field goes to the RIGHT hemisphere. Normal brain: Where the corpus collusom is intact. We flash a flower I the right hemisphere, the left hemisphere will know about the flower. This is because the hemispheres communicate with each other. Split brain: If we flash a flower to the right hemisphere, because the corpus collusom is cut off, the left hemisphere will NOT know about the flower. The left hemisphere is clueless about the flower. Left hemisphere: Controls the right side of the body, and controls language. Right hemisphere: Controls the left side of the body V – Peripheral Nervous System: It consists: It consists of all the nerves in the body that are outside the central nervous system (Example Nerves in arms, feet, leg, etc.). It connects: It connects the body to the external world, and it connects the body to the central nervous system. Main: Its main job is to carry information between the body to CNS and vise versa. 2: Main divisions PNS Somatic Autonomic  Somatic NS: It has two main functions; sensory and motor functions. Sensory: Our senses collect information from the world as well as from our own bodies, and they send this information to the central nervous system via sensory neurons. The axons of the sensory neurons are called afferent axons because they carry information from the body/the external world to the CNS Motor: Motor functions will carry motor information from the central nervous system to skeletal muscles via motor neurons. The axons of the motor neurons are called efferent axons because they carry information from the CNS to the body  Autonomic NS: It controls: Glands, organs, visceral muscles. Visceral: Muscles we don’t voluntary control (example: muscles of the heart). 2: Autonomic nervous system carries two divisions. Autonomic Sympathetic Parasympathetic SYMATHETIC NERVOUS SYSTEM PARASYMPATHETIC NERVOUS SYSTEM The system energizes and arouses the When the threat is gone, this system kicks in. body. PNS relaxes and calms the body down. It mobilizes the resources of the body It helps the body conserve energy  It prepares us to fight or flight. It helps the body repair itself. Fight or flight Rest and digest The 2 systems: Have distinct functions. However, they are constantly working together to maintain the balance of the body and hemostasis. Please do not ever post online and do not ever distribute. All rights reserved. Thanks! :) VI. The Endocrine System What is it?: It is a major communication network. It consists: It consists of all the glands in the body. Those glands release hormones directly into the blood stream. Example: Pineal gland (Found in brain; releases melatonin, the sleep hormone; regulates sleep- wake cycle) Hormones: Hormones are chemicals and they carry messages from the endocrine system to the body system, as well as to the brain. Hormones influence both physical processes, as well as mental processes. 3: We have three major types of hormones. Homeostasis: Some hormones are linked and associated with homeostasis. Example: Insulin Reproductive: Example: Testosterone, estrogen Stress: Example: Epinephine, cortisol Pituitary Gland: It is the master gland of the endocrine system. It is the master gland because it is the boss of almost all the other glands of the endocrine system. Hypothalamus: It is the gland that controls the pituitary, and that controls the rest of the endocrine system. NS & Endocrine System: They have distinct functions. However, they are constantly influencing and affecting each other. The nervous system controls the endocrine system via the hypothalamus. The hormones of the ES (endocrine system) influence and affect the NS (nervous system), including the brain. Affect behaviours: In psychology, hormones affect behaviours, and that is what psychology studies. Hormones influence and affect mental processes, and behaviours. Chapter 5 Sensation & Perception I to V. I. Basics of Sensation: A & B: A. The Musts of Sensation: 3: Things must happen Detection: We must be able to detect the stimulation coming from the external world. As humans, we can’t detect all the stimulation that is out there. Our senses are amazing, but they are limited. 2. Transduction: It means translation; In order for us to sense, the stimulation that is detected from the external world must be transduced. That means it must be translated into a message that the brain can understand. Transmission: The message must be sent in the brain for further analysis. Sensory receptors: The sensory receptors do not respond to neurotransmitters. They respond to stimulation and energy from the world. They are the ones detecting the physical energy, transducing it, and transmitting it. Bottom-up processing: This means our senses collect raw data from the external world. With the sensation, we start from scratch and we build up. B. Measuring the Senses: 1. to 4. Psychophysics: It’s a field of research within psychology. This is the scientific study of the link (or relationship) between the characteristics of the physical world, and our psychological experiences of them. Absolute threshold: It’s the minimum amount of energy/stimulation that must be there in order for us to detect it 50% of the time.  Difference Threshold (JND): It’s not enough for us to detect an energy; it’s essential for survival that we can detect changes in stimulation. It is the minimum amount of changes in stimulation that must take place in order for us to detect it 50% of the time. Webber’s law Explore and discover in the book. I may ask you a question about it on the first midterm Signal detection theory: According to this theory, our ability to detect stimulation/energy does not depend ONLY on how strong the stimulation is. Rather, a number of different factors will influence and affect our abilities. Examples of factors that influence our abilities to detect stimulation/energy are motivation, emotion, health, if we are tired or not, our expectations, assumptions, beliefs. II. Basics of Perception: Definition: Perception is the meaning of what you’re looking at. This is when the brain takes the raw data collected by our senses, analysis it and interpret it in a meaningful way. Top-down processing: Perception is a top-down process. The brain is going to interpret information in a meaningful way. That means the brain is going to use its existing knowledge, past experiences, beliefs, assumptions, expectations, etc, in order to interpret the information The ?s: Is it possible to have sensation, but not to have perception? Yes. An example is prosopagnosia. Prosopagnosia: These are people who can see properly. However, they can not proceed faces, they can’t recognize the faces of people they know, sometimes including their own. The ?s: Is it possible to have perception without sensation. Yes. Examples are hallucination, and being under the influence of drugs III. Vision: It is the most studied sense. A to D. A. The Stimulus: There must be: In order for us to see, there must be light. Electromagnetic radiation: Light is a form of electromagnetic radiation, which travels in the form of a wave. Electromagnetic spectrum: Light is part of the electromagnetic spectrum. We can only detect a very tiny portion of the spectrum. It falls between UV (ultraviolet) rays and infrared rays 400nm to 700 nm: Humans can only detect 400 to 700 Nanometers (nm) Visible light: 400nm to 700nm 2: There are 2 physical characteristics of the light wave that are of interest to us. Wavelengths: Distance between the wave peaks. A wavelength is a physical characteristic that is going to translate into the psychological experience of colour or hue. There is NO COLOUR in the external world. The colours we see are light waves, and the brain will interpret it as a colour. Hue: Long Wavelength (WL) Red Medium WL Green Short WL Blue Amplitude: It’s a physical characteristic, that is about the height of the wave. It translates into the psychological experience of brightness. Brightness: B. The Eye: In order for us to see, light must enter the eye and it must reach the retina. B.1 to B.3 B.1 Structure: Study straight from the book the different parts of the eye. Retina: It is found at the back of the eye, and it consists of multiple layers. B.2 Retina – Structure: From innermost layer: Rods & Cones: These are the sensory receptors of the eye. They are connected to bipolar Cells. (See later) Bipolar C.: Bipolar cells are connected to ganglion cells. Ganglion C.: The axons of the ganglion cells are going to bunch up together, and they form the optic nerve. Optic nerve: It leaves the eye to transmit the information to the brain. Blind spot: This is where the optic nerve leaves the eye. If light hits it at this point, we will not be able to see anything because we DON’T have rods and cones there. Fovea: It is at the center of the eye. When we see fine details, this is because of the fovea. It is responsible for our visual acuity. B.3 Rods & Cones: Are the sensory receptors of our eyes. Photoreceptors: They are the ones that detect the light, transduce it, and transmit the information to the brain. They differ in a variety of ways. Shape: They differ in shape. Number: They differ in number, where the rods outnumber the cones. Location: They differ in terms of location. The cones are highly concentrated in the fovea, and there are fewer of them in the periphery. Rods are only found in the periphery Connections to bipolar cells (see slide that I have created for you below) They differ in their connections to bipolar cells. Function: They differ in their terms of their function. Cones are not very sensitive to light; they need a lot of light to activate them (used more in day time). Cones allow us to see colour, and they are also responsible for our ability to see fine details. Rods are super sensitive to light; they need a little bit of light to activate them (used more in dark, dim, and night time). When we are using our rods, they do not allow us to see colours, such as red, blue and yellow. They help us detect motion and visual objects in our periphery.  Please do not ever post online and do not ever distribute. All rights reserved. Thanks! :) *** Chapter 5: Sensation & Perception LECT 2 C. Visual Information Processing (1 to 4):  Information processing in order of increasing complexity: 1. Retina: Processing of visual information begins at the level of the retina with bipolar cells. Ultimately, the information will reach the thalamus. 2. Thalamus: After further processing, the thalamus (Lateral geniculate nucleus, LGN) will relay it to the visual cortex. 3. Visual cortex (Occipital lobes): Contains feature detectors (highly specialized cells that are maximally responsive to very specific stimuli). Explore and discover (book): what is the difference between a simple cell and a complex cell? 4. Parietal, Temporal Lobes & Limbic System Dorsal stream: “Where” pathway (where is the object located in space/how far away is it?) Ventral stream: “What” pathway (what are we looking at?) Limbic system: Adds the emotional experience to what it is were looking at. D. Colour Vision (D.1 to D.3): How can we/do we see colour? D.1 Young-Helmholtz Theory/Trichromatic Theory Trichromatic theory: When the theory was first proposed, people knew that there are 3 primary light colours. Three primary colours (red, green, blue) can be combined to create the millions of colours that humans see. Therefore, the trichromatic theory posits that there must be 3 different types of cones in our retina (red cones, green cones, blue cones); each cone is maximally responsive to a very specific light colour. Ex. the red cones are maximally responsive to the red colour of light. R G B The brain is constantly monitoring the activity of these 3 types of cones; what type is being activated, in what combination and to what degree? Based on this, the brain will determine the colour it will see. D.2 Opponent-Process Theory: Hering: acknowledged the value of trichromatic theory but felt that on its own it could not sufficiently explain coloured vision. Ex. it doesn’t explain complimentary afterimages. Complimentary Afterimages: Complimentary images are the colours that we see upon staring at a colour and then looking at a white surface. (ex. stare at blue, you’ll see green when you look at white; stare at green, you’ll see blue). Hering proposed that 4 primary light colours: red, green, blue, yellow. He also proposed that in the visual system, there are 3 antagonistic colour systems. Example: RG/BY/BW - The neurons in this system are maximally responsive to both red light and green light. However, they respond to these lights in opposing ways. In this example, when the red light comes in, neurons will respond with excitement. On the other hand, when a green light comes in, the neurons response in an opposing way/with inhibition to the green light. This informs the brain; when the brain notices that the neurons are inhibited, it knows that it’s a green light and so, you will see a green light. The brain constantly monitors to see what’s being excited and what being inhibited in what combinations and uses this to determine what colours we will see. D.3 Bottom Line (To Date): - Both theories are needed to help us understand colour vision. - Trichromatic theory: Cones (Retina) - Opponent process: Ganglion cells (Retina) + neurons in the brain (e.g., Thalamus) IV. Organization & Interpretation: Introduction (A to F): Gestalt Psychology: Does not exist anymore today. Its main research question was: How does the brain organize information connected by our senses? A gestalt is a form. When we look at something, the brain perceives a “gestalt” (a meaningful form/whole), as opposed to fragmented shapes/images. Thus, this theory posits that a whole may exceed the sum of its parts. The perceiving brain doesn’t perceive the world passively. It uses its knowledge, experiences, assumptions, beliefs, expectations, context to create reality. The brain constructs reality. EARN A POINT: Study in the book: Gestalt principles and Depth Perception. Guaranteed there will be questions on the first midterm from this section. Hearing (Audition) (A to E): A. The Stimulus: soundwave(s). Sound wave: Soundwaves travel in the form of vibrations, enter the ear, then are processed/translated by the brain into the psychological experience of hearing. The 3 characteristics of the soundwave: 1. Frequency: How many times a soundwave peaks per second/the distance between the peaks. Frequency is measured in hertz (Hz). Humans can only detect soundwaves of 20 to 20 000 hz. Frequency is a physical characteristic that translates into the psychological experience of pitch. o Pitch is how high or how low a sound is, NOT how loud. 2. Amplitude: Amplitude means the height of the wave. It’s measured in decibel (Db). It’s a physical characteristic that translates into the psychological experience of loudness. 3. Complexity: The complexity of the soundwave gives the human voice its unique characteristic. It’s a physical characteristic that translates into the psychological experience of timbre B. The Ear Pinna: captures the soundwaves and funnels them into the auditory canal. The soundwaves will travel in the auditory canal until they reach the eardrum, causing it to vibrate. Auditory canal: carries the soundwaves to the eardrum. Eardrum (Tympanic membrane): The vibration of the eardrum causes the ossicles to create the oval window. Ossicles: The (3) tiniest bones in your body (learn the names in the book). The vibration of the ossicles will cause the vibration of the oval window. Oval window: A membrane in the ear that will vibrate as a result of the vibration of the ossicles. Cochlear fluid (cochlea): The vibration of the oval window causes the fluid inside the cochlear to form waves (cochlear fluid). Basilar membrane: The waves in the cochlear will cause the basilar membrane to vibrate. Hair cells (cilia): The vibration of the basilar membrane causes hair cells to sway. This activates them and causes them to send the information to the brain via the auditory nerve. Auditory nerve: Carries the information to the brain. The auditory nerve will carry the information to the brain. Below are a couple of stops: Thalamus MGN (medial geniculate nucleus): The information is first sent to the thalamus. Auditory cortex (temporal lobes): Then, the information goes form the thalamus to the auditory cortex. Explore and discover (book):  What does tonotopic organization mean?  According to the book, some neurons that process auditory information tend to have faster action potentials and larger terminal buttons. Why?   Simple sounds are processed ___________________ whereas complex sounds are processed _____________________ A. How do we Perceive Pitch?:  2 theories: Research seems to show that that both theories are needed to understand how we perceive pitch. 1. Place Theory: Sound waves of different frequencies will cause the basilar membrane to vibrate in different locations. According to this theory, high frequency soundwaves will cause vibrations at the beginning of the basilar membrane (HF sound waves). Low frequency soundwaves will cause vibration at the end of the basilar membrane (LF sound waves). 2. Frequency Theory: The frequency of the soundwaves influences and effects the range of firing of the hair stems. 1 hertz will create 1 action potential (1 hz = 1 a.p.). B. Locating Sound:  2 binaural cues on which the brain relies to locate sound: 1. Time of arrival: This is known as inter-oral time differences. The ear closest to the sound source receives the soundwave first. The ear that is furthest will receive it second. This difference in timing informs the brain. 2. Loudness: This is known as inter-oral level differences. The ear closest to the source of the sound will perceive the sound to be louder than the ear that is further away, because as the sound enters the first ear and travels through flesh and bone, it becomes muffled. This difference in loudness informs the brain and that’s how it locates the sound. Both: What if the soundwaves hit both ears at the same time? You may use your other senses to detect where the sound is coming from. Ex. you can use our vision to see who’s speaking, or tilt your head, etc. GENTLE REMINDER This is not to be posted online, or distributed, in any shape or form. Not now and not ever. Thanks :) VI. Other Senses: A To D: A. Skin Senses: A.1 A.2 Chapter 5 Sensation & Perception Lecture 3 A.1 Introduction: Our skin is our largest organ in our bodies, It is protective of our Organs, and it connects our bodies to the external world. Cutaneous senses: Touch is one of the sensations experienced with skin. We detect a variety of different sensations with our skin(e.g. hot/cold temperature can be felt with our skin) Receptors: In our skin, we have a variety of receptors helping us pick up a variety of sensations that we can experience. (e.g. the Mechanoreceptors) Mechanoreceptors The following info is based on the book. Explore and discover what are mechanoreceptors? Top layer of the skin Merkel receptor: Pressure (touch) Example: Your friend holds your hand. As soon as she/he holds your hand, they will start firing and they will continue to do so for as long as your friend continues to hold your hand, They will stop when she/he lets go of your hand. This allows for fine details to be transmitted to the brain Meissner receptor: Pressure (touch) Deeper layers of the skin Ruffini cylinder: Example: Your friend holds your hand. As soon as her/his hand makes contact with yours, they fire. As long as he/she is holding your hand they will not fire. They will fire again when your friend removes her/his hand. Stretching of the skin Pacinian corpuscle: Vibration Texture Importance of touch: Touch is essential for our physical and mental well-being. A.2 Pain: A.2.1 Introduction: Nociceptors: All over our bodies we have Nociceptors. These are the sensory receptors for our sense of pain. Basically, they’re the ones that are going to detect, transduce and transmit. Survival: Experiencing pain is essential for survival. Pain alerts us that something is wrong, and with that we can take action. Complexity: The experience of pain is highly complex. The amount of pain we feel does not only depend on the type of tissue damage. There is a number of factors that can influence and affect our experience of pain (e.g. emotions, motivation, culture) A.2.1 Gate-Control Theory: A theory attempting to explain the complexity of pain. According to this theory there is a neurological gate in the nervous system. Neurological gate: The state of that gate would influence and affect if we feel pain and how much pain we experience. If the gate is open, we’re likely to experience pain, if the gate is closed then we’re likely to feel little to no pain. We also have small nerve fibers, and large nerve fibers in our system. Small nerve fibres (S-fibers): When the S-fibers are active, they tend to open the neurological gate because they mostly carry pain information, so they tend to open the door and we’re likely to feel pain. Large nerve fibres (L-fibers): Large nerve fibers on the other hand, tend to carry mostly information that isn’t related to pain. (e.g, if it’s cold or hot) and because of this they’re likely to close the neurological gate and we’re likely to feel little to no pain. T – cells (middle men): T-cells mediate between the fibers and the gate. The T-cells have to be activated for the neurological gate to open. When small fibers are activated, they activate T-cells. When large fibers are activated, they de-activate the T-cells. Must be activated for the gate to open. Stimulation: We have a number of factors that could affect the brain. (i.e, stimulation of a certain brain area can close the gate and we can feel little to no pain.). Stimulation of a certain brain area, it doesn’t matter which one, could close the gate, and we could feel little to no pain. Beliefs: Our beliefs could influence and affect the gate, thereby influencing and affecting our pain. (e.g, placebo affect) Placebo effect: Stress: Stress can open or close the gate. (e.g, If one day, a bear is running after us, and we fracture our ankle, the body’s priority is to escape the bear and survive. Even if our ankle is fractured, we’re not likely to feel the pain in the moment. Once the bear is gone, then we’re going to feel all the pain.) Other factors: Our emotions could make a difference: Emotions: Self-confidence: When we’re confident, even if we have the same type and same amount of injury, we’re going to feel less pain than on the days we’re not as confident. Culture: Even with the same type of injury, same amount of injury, people from different cultures will have different levels of pain. (i.e. faith) B- Smell (Olfaction): Chemical sense: The stimulus for our sense of smell are odor molecules released by objects. In order for us to smell something, those odor molecules must enter our cavity. To smell something, we have to inhale. They must come into contact with our olfactory receptors (ORN) Olfactory receptors (ORN): The olfactory receptors are the sensory receptors for our sense of smell. They detect, transduce, and transmit. Olfactory epithelium: The olfactory receptors (ORN) are embedded in our olfactory epithelium. It’s inside our nose, and it’s a membrane filled with mucus. Glomeruli (inside the olfactory bulb): Information from the Olfactory receptors is going to go to the G’s (Glomeruli) and the G’s are located inside the olfactory bulb. Ex: Temporal lobes; Limbic system: The information from the olfactory bulb is going to be sent to various parts in the brain. (i.e, the limbic system.) Millions: We have millions of olfactory receptors (ORN) and they can be organized into 300 million different types. > 300 # types : Our millions of ORN can be organized into over 300 different types. 10 000 odours: For the longest time, researchers thought that humans could only detect 10,000 odors. Over 1 trillion odors: Modern research suggests that we can detect over 1 trillion odors. How do we detect trillions of odors with only >300 types? Researchers believe different odor molecules will activate a different combination of receptor types. Fictional examples: Odour A = 1 +250 + 319 Odour B = 2 + 16 + 29 + 105 Regeneration: Every six weeks, ORNs regenerate. Ageing: They regenerate, but that doesn’t mean we keep the same numbers. Things like smoking, pollution can hurt them and affect their numbers. By the time we’re 65 25% of us will have problems with out sense of smell. So even though they regenerate, we don’t keep the same number of ORNs. 65  25% 80 75% Emotions & memories: There is a strong link between our sense of smell, emotions and memories. There is that link because smell information is sent to the limbic system, and the limbic system is linked and associated with emotions and memories. C. Taste or Gustation Essential: For our ancestors their sense of taste was essential for their survival. Chemical sense: Our sense of taste is a chemical sense. Molecules from the food we eat, beverages we consume. In order for us to taste: To be able to taste, those molecules must dissolve in our saliva, and they must come in contact with our gustatory cell. Gustatory cells: Gustatory cells detect, transduce, and transmit. They are the sensory receptors of our sense of taste. They are found: Gustatory cells are found in our taste buds. Papillae: Our taste buds are found in the papier, the bumps on the tongue. Explore and discover (book): 1. List the different types of papillae named in your book 2. Make sure to know where they are located 3. Name the one type of papillae that does not contain taste buds 4 basic...: SSSB For the longest time, researchers believed that we had 4 basic taste functions. Sour, Salty, Sweet, and Bitter. (SSSB) 5th Umami: Japanese researchers discovered a 5th taste sensation, and that’s the taste of umami (or yummy) and it’s the taste of savory foods (meat, fish, cheese, mushrooms, tomatoes) 6th Fat?????? Some researchers believe that we may have a sixth taste sensation, and that’s fat. This is partially because healthy fat is an essential part of a healthy diet. Regeneration: Our gustatory cells are very fragile. You can easily kill them (e.g. if you drink hot coffee, or hot soup). If you smoke or drink alcohol, you can hurt them. Every 10 days they regenerate, however we do not keep the same numbers. By the time you are 20, you would have lost half of your gustatory cells. Sensory interaction: Sensory interaction – our different senses may interact and influence one- another. Our sense of taste and smell definitely do interact and influence each other. Explore and discover (book): 1. What are bimodal neuron and where are they located? D. Body Position & Movement Kinesthesis: The K-sense, a sense where we can know where our bodies are, where they’re located in space, what position they’re in, if they’re moving or not, how fast they’re moving, if they’re relaxed or contracted. In our muscles, in our tendons, in our ligaments, in our joints, we have proprioceptorr. These are sensory receptors of our k-sense. Vestibular sense: The vestibular sense helps with balance and orientation, and motion. It works closely with our sensory systems. It works with our vision and proprioceptors to help us navigate and move smoothly. Explore and Discover (book) 1. Our vestibular sense is also known as our sense of..............? 2. List the 2 organs linked and associated with our sense of balance. 3. They are located in your inner ear 4. For each organ, make sure to know what they sense or respond to 5. How do we know that our vestibular sense is integrated with our sense of vision? 6. The sensory receptors for our vestibular sense are............?