Psychology Poster Answers#1 How do we perceive color?
The grass isn't green. Color is not a property of things; it is a product of the human brain. We perceive color when specialized cells in the eye, called photoreceptors, respond to light. Different objects reflect or absorb different wavelengths of light. Different kinds of photoreceptors respond to different wavelengths of light and the eye sends a signal to the brain that is interpreted as color. Grass reflects green light and absorbs light of other wavelengths (e.g., yellow, blue, red) and blue birds reflect blue light and bananas reflect yellow light. Color perception helps us see and interact with objects more effectively.
#2 How do we form memories?
We don't yet know the full answer to this question. What we do know is that your likelihood of forming a strong memory for an event is dependent on how much attention you pay to it, how many connections you draw between it and earlier memories, and how strong your emotions are at the time. At the neural level, the hippocampus is important for creating new memories, but the finished product is stored elsewhere in the brain--probably in the association areas of the frontal cortex.
#3 How does the mind represent reality?
Drug studies show that our sense of reality can be fragile and shifting. Perceptions as well as memories are actively constructed as an amalgam of experience and inference colored by context and emotion. For example, science has demonstrated that we recall things better if we are in the same situation as the one in which we first learned. Gary Marcus' book Kludge: The Haphazard Construction of the Human Mind offers great insight into this.
#4 How do people learn?
People learn in many ways. One way is by observing what other people do, but it's not simply a matter of being in the same room. You're more likely to learn from someone if you're rewarded for paying attention to them, if you've seen them get positive results for their actions in the past, if you consider them to be similar to yourself, or if you respect and admire them. If you have many possible role models available, you're most likely to imitate the ones who share several of these characteristics.
#5 How do people understand and produce language?
Humans seem to be "hard wired" for language. Infants are born differentiating between and making all the sounds found in every language known. However, if they do not hear a sound reproduced by those who are talking around them, they loose the ability to differentiate or to make a sound that is not found in their cultural language. Babies learn by listening, and by engaging in "conversations" with adoring others, who reward them with smiles and hugs when the baby produces a sound that is recognized as a word -- such as "ma ma" or "da da". Gradually the baby learns to associate specific meanings with word sounds, and growth in vocabulary is astonishing during the first five years of life. Humans also seems to be wired for grammar. Even small children quickly produce patterns of speech that indicate they recognize past tense -- even though it takes longer to learn the exceptions (such as "I runned fast!"). English is a challenging language to learn because there is a large vocabulary and many exceptions to rules of grammar and spelling. While other animals clearly have ways of communicating to each other, human language systems are probably the most complex and flexible systems of communicating.
#6 How do various diseases and injuries of the brain affect emotion, perception, and behavior?
There are many diseases and injuries that affect thinking, emotions, and behavior. Sometimes only one function is affected but often all are changed in some way. By studying these effects psychology and neuroscience are making discoveries about the links between these functions and how the brain works. A great beginning resource for this topic are the books by neurologist Oliver Sacks, for example The Man Who Mistook His Wife for a Hat. In these books Dr. Sacks eloquently describes how brain damage and disease lead to very unusual experiences in people's experiences of themselves, other people, and the world around them.
#7 How does brain chemistry affect mood?
When you read this, I am changing changing your brain chemistry! All of our sensory experiences (seeing, hearing, feeling, smelling, tasting) send messages to our brain that make chemical changes. (Actually, it's more accurate to say that we see with our brains using information from our eyes, and similarly for all the other senses.) Likewise, all of our internal experiences (thoughts, emotions, etc.) have parallel representations in the chemistry of our brain. Finally, chemical changes in our brains, from illness, accident, or intentionally (e.g., treatment) may change our conscious experience (although exactly what chemical changes lead to what experience changes usually isn't so clear). Thus, it really isn't best to separate the chemistry and the mood (or other experiences) into two different things (not to say that they are exactly the same). There is a long tradition in Western thinking that separates the mind and the body (e.g., the French philosopher Descartes), but more modern scientific thinking makes an effort to consider them together.