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In the space provided below, write a thorough summary of your presentation/lesson as it relates to the related objective:

Explain how biological factors may affect one cognitive process.

The summary should follow the chronology of the oral presentation, but feel free to adjust anything so that it reads fluently and logically. Also, be sure to hyperlink to your research studies, activities, and/or any other relevant web-based information related to the content of your presentation.



Perception (Sight)


General Information on the Eyes
Human eyes are about the size of a ping pong ball. The eyes sit in a special part of the skull; the eye sockets (aka the orbit). The visible parts are protected by the eyelids and eyelashes. The eyes are controlled by 6 muscles (the extraocular muscles) on each eye, they almost always move together.
The Eye is Made in Layers
The eye is made up of 3 different layers. The outermost layer is the sclera. The middle layer is made up of the choroid. The final layer is made up of the retina
The Visible Part of the Eye
Only part of the eye is visible: including the sclera, the iris, and the pupil. The sclera is the white part of your eye that is the outside layer of the eye. It is attached to the cornea which protects the rest of the eye. The cornea is a clear front surface on the eye (kind of sticking out like a dome). The cornea is filled with aqueous humor, a liquid that helps it focus the light into the eye. The cornea with the aqueous humor acts as an outer lens in the eye that does most of the eye’s focusing. The iris is the colored ring of the eye. It controls the size of the pupil, making the pupil larger or smaller to take in more or less light. (like a camera shudder). The pupil is the little black hole in your eye. It takes in the light to the rest of the eye. When more light is being taken in the pupil is larger, and vice versa. (aka, when it is dark, your pupils are bigger, and when it is really bright your pupils are smaller.)
Inside the Eye
The first thing you come to once you go past the pupil is the lens. It is just behind the iris and is much like a camera lens. The lens further focuses the light entering the eye and sends it on into the rest of the eye. In order to focus on things that are different distances away the lens has to change shape. This is done through the ciliary body. The ciliary body contains the muscles that actually bend the lens to focus the image. After the lens there is a (relatively) large space. This space at the center of the eye ball is filled with another liquid. This liquid is called the vitreous humor. The vitreous humor allows light to pass though to the retina in the back of the eye and it also helps the eye keep its round shape.
The retina contains some very important parts to our eyes; the rods and cones. On each retina there are about 120 million rods and 6-7 million cones. There are far more rods than cones (obviously). The rods only see in black & white (and shades of gray) and they are more sensitive to color. The cones are less numerous than the rods and less sensitive, but they can sense color. There are thought to be 3 types of cones, all sensing a different color. The combination of these 3 colors makes all of the colors in the world. The three colors that cones can “see” are RED, BLUE, and GREEN. Rods are about 1000 times more sensitive than cones.
The rods and cones then convert the rays of light into neuronal impulses (electronic impulses) that travel through the optic nerve at the back of the eye to the brain where they are interpreted. The optic nerve takes the impulses to the visual cortex in the brain. The visual cortex is located in the occipital lobe in the back of the brain.
How the Eyes Work Together
Most people have 2 eyes. When we use both eyes to see it is called binocular vision. Because the eyes each see at a slightly different angle the brain interprets the 2 images together and allows us to see 1 image. With 2 eyes we are better able to judge depth and distances. (Depth perception)
Problems with Vision
Problems include things like: Blindness (can’t see), Color-blindness (can’t see or distinguish colors), Astigmatism (blurry vision), Near/farsightedness (can only see things close or far away), and other common eye infections (like pink eye, ect…)
Link to Research: http://www.pigeon.psy.tufts.edu/avc/kirkpatrick/default.htm
Link to Vision Activity: http://www.exploratorium.edu/exhibits/changingill/



Perception (Taste & Smell)

Perception:
Combination of the five senses are processed in the brain and are closely linked to memory.
Importance of Taste and Smell:
Flavour and taste are different. People who smell pleasant odors are more motivated, have better appetite, and like to social. Taste and smell also trigger memory. Often times memories that have been forgotten can be remembered after tasting/smelling something familiar, or related to that memory.
Chemosensation:
There are millions of receptors in our nose and on our mouth, but sadly, the numbers greatly decrease as we get older. People who have more sensitive taste don’t “train”, they just have more taste buds.
Gustatory System Process:
(à this thing is supposed to be an arrow poingting right, indicating the direction of the process)
Papillae bumps à gustatory receptors à Neuron à Cranial Nerves à Brain Stem à Hypothalamus OR Thalamus à Sensory Cortex
Olfactory System Process:

Olfactor Epithelium (receptors) à Olfactory bud (sums up information and sends to brain à through axons of the olfactory nerves, which leads to the temporal lobes of the cerebral cortex à Primary Olfactory Cortex: higher-level processing of smell forms a direct link with the amygdala and hippocampus. (frontal cortex recognizes)
Stronger smell means more molecules diffused in the air, and the same could be said for taste.
*Both senses are also sent to the amygdale and hippocampus limbic system
Disorders:

Smell
¨ Conductive Defects
Foreign objects in the nose, or something that would either clog or block the nasal canal.

¨ Central/Sensorineural defects
when the part of the brain is affected, either stretched or cut, or deformed do a stroke.
Taste

¨ Smell dysfunction
Whatever the nose has been damaged with, affects taste.
¨ Lesions
Cuts on the tongue can cause taste buds to interpret tastes differently
Research Study:
Taste’s affect on weight reduction

Link: http://www.smellandtaste.org/index.cfm?action=research.sprinkles
Olfaction Research Studies:

http://www.macalester.edu/psychology/whathap/ubnrp/smell/memory.html
The best one:
http://www.physorg.com/news180716870.html
Movie on Taste and Smell: (the whole movie is on perception as a whole, this part only talks about taste and smell)
http://www.tudou.com/programs/view/WsOx2ffjWJU/


Useful Links if you still don't understand it (animations):
http://www.bbc.co.uk/science/humanbody/body/factfiles/smell/smell_animation.shtml
http://www.bbc.co.uk/science/humanbody/body/factfiles/taste/taste_animation.shtml




Language


What Is Language?
Language can be defined as a system of communications that enables one to understand, predict, and influence the actions of others. The brain analyzes speech and tries to detect patterns. Initially, the brain analyzes passages for literal meaning. However, if the literal interpretation doesn’t make sense, the brain then reprocesses the words in order to find an appropriate figurative meaning.

Biological Processes
There are a few biological processes involved in the cognitive process of language comprehension. The left hemisphere of the brain is responsible for processing literal language, while the right hemisphere of the brain is responsible for decoding figurative expressions. It is believed that our ability to learn spoken language is developed through the evolutionary process and that the foundation for language is passed down through genetics. Our ability to speak and understand language requires a specific vocal apparatus as well as a nervous system with certain capabilities. For about 50 years, linguist Noam Chomsky has theorized that humans are biologically prewired to learn language in a certain way and at certain time. He also theorized that all children are born with a Language Acquisition Device. However, other researchers believe that words and grammar are learned and aren’t innate and they also believe that learning language is a result of general cognitive abilities, as well as the interaction between other people and their surroundings. Recently, it has also been suggested that the slow development of the prefrontal cortex may be a reason for why humans are able to learn language.


Activity:
In this activity, remember Steffon was blindfolded, read sentences and asked if those sentences made sense. Remember, how some sentences did and some didn’t because of how the syntax of the sentences wasn’t correct. We couldn’t derive any meaning from them. At the start of the activity I also pointed out that all languages have phonemes, the basic sounds of words and morphemes, the additional sounds added to words like prefixes and suffixes. The activity was also used as a heightening of awareness to where in the brain literal sentences and metaphorical sentences are processed.
Research:
Rapp and the investigation of Neural Correlates of Metaphor Processing is a research study that can be read about in the handout on language that Mr. Galvez gave us. Basically it’s a study that was devised to further establish theories already in practice, namely the “laterality” model that predicts that the left hemisphere of the brain is used to find the literal meaning of a sentence and that the right hemisphere is used in the understanding of a metaphorical sentence. Think back to the activity or read the above paragraph. The conclusions of this research study was that yes, the left hemisphere deals with literal translations and the right hemisphere with metaphorical translations. But what surprised the researchers was that other parts of the left hemisphere than the parts for the literal translations are used in addition to the right hemisphere when trying to figure out metaphorical sentences. This implicates that other factors of the mind play parts in the understanding of metaphors.
Babies and language: this was the investigation of how babies understand and acknowledge vowel harmony as a learning tool for languages. What was cool about this investigation is that it applies to all babies. And that it is thought of as a function that is ‘hardwired’ into the human mind for learning languages. This is also a topic that needs more investigation, just as it is suggested in the clip on YouTube: http://www.youtube.com/watch?v=mZAuZ--Yeqo



Brain Damage
Brain damage can greatly affect one’s speech and language comprehension. The left hemisphere of the brain is more densely wired and structured for language than the same part of the right hemisphere; it controls our speech and language abilities. In 1861, Paul Broca discovered the left hemisphere’s role in language. A stroke on the left side of the brain can lead to aphasia, which is a wide range of speech and language problems. These problems can range from slightly slurred speech to even total illiteracy. Sometimes these problems can be very specific. For example, the stroke might only affect one part of a person’s ability to communicate, such as being able to move their speech-related muscles properly in order to talk. However, the same person might be completely unaffected in terms of writing, reading, or understanding other people’s speech. Wernicke’s area is the central speech processing center of the brain. Strokes that occur in this area often lead to slurred speech and affects language comprehension. Also, one’s reading ability may be affected, as well as recalling the names of familiar people, places, or objects.
**Link to Brain Damage Video** - (Click "Chapter 5: The Nervous System")




Memory

Memory, in psychology, is the ability to store, retain, and recall information. The information can range from various events, experiences, information, or skills.

Short Term Memory (STM)
Most short term memories are stored in the Prefrontal Lobe.
STM is essential for remembering things we plan to do.
Working memory is a concept of STM, and is used to perform cognitive processes on the items that are temporarily stored in it. Example: hearing a phrase in one language and orally translating the phrase in another language.


Long Term Memory (LTM)
The purpose of encoding is to assign a meaning to the information being memorized. How effectively you can retrieve information depends on how deeply you have encoded it, and hence how well you have organized it in your memory. The process of encoding refers not only the the information being memorized, but also its environmental, cognitive, and emotional context.
Storage is the creation of a biological trace of the encoded information in memory, which is either consolidated or lost. It is this consolidation that differentiates memories of recent facts from memories of older ones.
Retrieval involves active mechanisms that make use of encoding indexes. In this process, information is temporarily copied from LTM into working memory.

LTM and the Brain
Information is transferred from STM to LTM through the hippocampus which acts as a “sorting center” because pieces of information decoded in various sensory areas of the cortex converge in the hippocampus and sends them back where they came from. It is also involved in explicit memory, including episodic memory. However, LTM usually don’t use the hippocampus after a long time.
Emotional memory is encoded through the amygdala and the limbic system, which is described as the degree of interest or how special it is to you. The more emotional a memory is, the better it will be encoded into the amygdala.
Procedural memory is stored in our basal ganglia and cerebellum, both of which are involved in motor control.


Memory and Neurons
Neural circuits are altered in your brain and these circuits are composed of a number of neurons that communicate with one another’s synapses. When you learn something, the efficiency of the synapses increases, thus helping nerve impulses pass along a particular circuit. All your memories thus correspond to the particular activity of certain networks of neurons in your brain that have strengthened connections with one another.
Activity
Purpose:
The fact that syntax changes or implied changes were difficult to identify as “new” shows that sentence meanings, not the surface characteristics of those sentences, were stored in long-term memory. The difficulty that you guys had in identifying implied sentence as “new” illustrates the reconstructive nature of retrieval from long-term memory; that is, we tend to remember “what must have been” rather than what actually was.
For example, given the words TOAD, WALL, BOOK, and SKY, a person in a short-term memory recall might recall TOAD, BALL, BOOK, and SKY. BALL may sound similar to WALL, but they have no similarity in meaning. On the other hand, a person recalling from long-term memory might say FROG, WALL, BOOK, and SKY. The word FROG sounds dissimilar to the correct term TOAD, but the meaning of the two words is similar.
This activity demonstrates the tendency to store in long-term memory in the brain the deep structure (ex. Meaning) of a message rather than the surface structure (ex. The specific words or physical stimulus characteristics) used in transmitting that meaning.



Research Study (http://www.nytimes.com/2008/12/05/us/05hm.html)

Patient HM

Key information from the article:

Patient HM’s original name is Henry Molaison, and was given the name “HM” to protect his privacy.
He knew his name, he knew that his father’s family came from Louisiana, and his mother was from Ireland, and he knew about the 1929 stock market crash and World War II and life in the 1940s.
But he could remember almost nothing after that.
When he was 9 years old, banged his head hard after being hit by a bicycle rider in his neighborhood, scientists had no way to see inside his brain. They had no rigorous understanding of how complex functions like memory or learning functioned biologically. They could not explain why the boy had developed severe seizures after the accident, or even whether the blow to the head had anything do to with it.
In 1953, he underwent an experimental brain operation in Hartford to correct a seizure disorder. The doctor decided to surgically remove two finger-shaped slivers of tissue from Patient HM’s brain. The seizures subsided, but the procedure — especially cutting into the hippocampus, an area deep in the brain, about level with the ears — left the patient radically changed.

He developed a syndrome neurologists call profound amnesia, which a syndrome where you lose the ability to form new memories.
For the next 55 years, each time he met a friend, each time he ate a meal, each time he walked in the woods, it was as if for the first time.

At the time, many scientists believed that memory was widely distributed throughout the brain and not dependent on any one neural organ or region.
That began to change in 1962, when Dr. Milner presented a landmark study in which she and H. M. demonstrated that a part of his memory was fully intact. In a series of trials, she had Mr. Molaison try to trace a line between two outlines of a five-point star, one inside the other, while watching his hand and the star in a mirror. The task is difficult for anyone to master at first.
Every time H. M. performed the task, it struck him as an entirely new experience. He had no memory of doing it before. Yet with practice he became proficient.

The implications were enormous. Scientists saw that there were at least two systems in the brain for creating new memories. One, known as declarative memory, records names, faces and new experiences and stores them until they are consciously retrieved. This system depends on the function of medial temporal areas, particularly an organ called the hippocampus, now the object of intense study.
Another system, commonly known as motor learning, is subconscious and depends on other brain systems. This explains why people can jump on a bike after years away from one and take the thing for a ride, or why they can pick up a guitar that they have not played in years and still remember how to strum it.
They saw that H. M.’s short-term memory was fine; he could hold thoughts in his head for about 20 seconds. It was holding onto them without the hippocampus that was impossible.
It opened the way for the study of the two memory systems in the brain, explicit and implicit, and provided the basis for everything that came later — the study of human memory and its disorders.”
He died on December 8th, 2008 at the age of 82 and is recognized as the most important patient in the history of brain science.