The Mind's Machine - Ch 1

The mind as a machine

Long history of using contemporary metaphors for the workings of the brain
1. scholars of old influenced by aqueducts and plumbing related behavior to liquid animal spirits jetting around the body
2. later, wires switches and relays
3. today, computer

mind

the perceptions, emotions, thoughts, self-awareness, and other cognitive processes that inform our behavior

modern research aims to describe the brain, but also how the operation of the brain produces the mind

Nature-Nurture Debate

Arguments over the extent to which mental characteristics and abilities are the result of learning experiences vs innate hardwired programs

Rather than one or the other, the answer is both

Rat pups who are neglected by their parents show elevated stress hormone responses to stressors that have little affect on non-neglected rat pups

Nature AND nurture
When the pups were neglected, this resulted in a change in their gene expression that lasted into adulthood. Thus, the pups were more susceptible to stressors. So, something that happened in their environment affected their biology

Neuroscience

the scientific study of the nervous system

the first scholars to study the relationships between brain and behavior were called

philosophers

what discipline established the scientific method as a tool for finding new knowledge

philopsphy

biological psychology

The study of the biological bases of psychological processes and behavior.

field that relates behavior to bodily processes

synonyms: behavioral neuroscience, brain and behavior, physiological psychology

Main Goal: understand brain structures and functions that respond to experiences and generate behavior

Made up of researchers from many different backgrounds (psychologists, biologists, engineers) and work spans from academia to industry.

As a science, biological psychology has a long past but only a short history...

objective experimentation and use of the scientific method in this field has a formal history of about 100 years, but people have been wondering about the origins of behavior for a LONG time

Relationship between early scholars and the brain

They did not understand its significance
The behavioral role of the brain was uncertain to early scholars
-Egyptians throw it out
-No mention in Quran or Bible
-Aristotle thought it was a cooling-off place for hot blood from the heart

Egyptian mummification process and importance to biological psychology

In ancient Egypt, it was believed that well-equipped individuals would have a better time in the afterlife, so they embalmed the body with salts and oils and preserved the four important organs, which were the stomach, lungs, liver, and intestines; the heart (most important) was kept in the body

The brain...was discarded like it was nothing.

This shows us that early scholars did not understand the role that the brain plays in behavior

Hippocrates

Father of modern medicine

*disagreed with Aristotle about the purpose of the brain (NOT a place for heart blood to cool off), believed it controlled emotion, perception, and thought

What propelled modern biological psychology

Advances in experimental methodology;
these newly developed tools helped researchers study mental processes that had previously seemed unknowable

Karl Lashley

Headed one of the first true biological psychology research programs; sought for the neural basis of learning; "search for the engram" (goal was to link a specific region of the brain to the formation of a single long-term memory

Result: memory is not localized to one region of the brain

Donald O. Hebb

neurons that fire together wire together
*Cognitive processing was accomplished by a network of active neurons molded by repeated activation patterns into functional circuits
*Neurons strengthen their connections as a consequence of experiences

Hebbian synapse

a type of plastic (changeable) connection between neurons

uses a time-dependent, highly local, and strongly interactive mechanism to increase synaptic efficacy as a function of pre- and post-synaptic activity

Major theoretical perspectives in biological psychology

1. systematic description of behavior
2. The evolution of brain and behavior
3. Life-span development of the brain and behavior
4. the biological mechanisms of behavior

Galen (2 CE)

The father of medicine

Experience in treating head injuries of gladiators led him to propose that behavior results from the movement of animal spirits throughout the nerves

More brain-centered view of mental processes

Leonardo DaVinci (1452-1519)

produced exquisite neuro-anatomical illustrations of nerves and brain structures during the Renaissance

The brain in the Renaissance

Religious dogma dominated Renaissance science

The brain was seen as a mysterious and intricate gift from God

It is believed that some held a more secular view, for instance, Michelangelo, who was thought to have been conducting dissections of cadavers

Rene Descartes

Explained how the controls of behavior might resemble a machine, proposing the idea of spinal reflexes and neural pathways for them.

Free will and moral choice could not arise from a machine, so humans must have a nonmaterial soul as well as a material body and that the soul governed behavior though a point of contact (pineal gland) in the brain

Dualism

The notion, prompted by Rene Descartes, that the mind has an inmaterial aspect that is distinct from the material body and brain

Today, biological psychologists reject this in favor of the idea that the workings of the mind can be understood as purely physical processes taking place in the material brain

Thomas Willis

English physician
Studied relationship between various disorders and damage to regions of the brain
*Gave rise to the notion that the brain coordinates and controls behavior

phrenology

Pseudoscientific fad in the 1800s that took advantage of the idea that specific behaviors, feelings, and personality traits were controlled by corresponding specific regions of the brain

the belief that bumps on the skull reflect enlargements of brain regions responsible for certain behavioral faculties

*thought they could read a person's character by feeling the bumps

*established the concept of localization of function

localization of function

the concept that different brain regions specialize in specific behaviors

Est. by phrenology

More or less true: although the whole brain is active most of the time, when we are performing certain tasks, some regions become even more activated, so modern functional maps of the brain track the locations where these peaks of activation occur

Paul Broca

researcher
found that damage to certain specific regions of the brain caused predicatble impairments in people
* found that damage to a particular region on the left side of the brain reliably causes problems with speech production

William James

wrote Principles of Psychology, which signaled the beginnings of a modern approach to biological psychology

psychological ideas such as consciousness came to be seen as properties of the nervous system

Biological psychology theoretical perspective: Systematic description of behavior

Until we describe what we want to study, we cannot accomplish much

Depending on goal, describe behavior as:
* detailed acts or processes
* In terms of results/ function

Description must be precise, using accurately defined terms and units

conserved

in the context of evolution, referring to a trait that is passed on from a common ancestor to two or more descendant species

Biological psychology theoretical perspective: lifespan development of the brain and behavior

Observes the way a particular behavior changes during ontogeny may give us clues to its functions and mechanisms

* Learning ability in monkeys increases over several yrs of development, so maybe prolonged maturation of brain circuits is required for complex learning

Biological psychology theoretical perspective: the biological mechanisms of behavior

* to learn about the mechanisms of an individual's behavior, we must study how his/her present body works (separate from evolutionary/developmental concerns), regarding the organism as a machine made up of billions of neurons

ontogeny

the process by which an individual changes in the course of its lifetime -- that is, grows up and grows old

neuron

nerve cell, basic unit of the nervous system

"how" questions in biological psychology

mechanistic (here and now

"why" questions in biological psychology

evolutionary and developmental perspective

prevalence of neurological or psychiatric illness

1 in 5 people currently suffers from one

neuroplasticity

(neural plasticity) The ability of the nervous system to change in response to experience or the environment

Certain experiences/phsyiological states can alter the rate at which neurons are formed in the adult brain

adult neurogenesis

the creation of new neurons in the brain of an adult

epigenetics

the study of factors that affect gene expression without making any modifications to the actual nucleotide sequence of the genes themselves

gene expression

the turning on or off of specific genes

methylation

the process of inactivating a gene

Discuss the concept of localization of function

certain regions of the brain are involved in the coordination of certain functions (while all of the brain is usually active most of the time, these regions become MORE active)

Describe the 4 major theoretical perspectives employed by modern biological psychologists discussed:
1. behavioral description
2. evolution
3. development
4. biological mechanisms

1. if you want to study a behavior, learn about a behavior, then you have to be able to describe it precisely and accurately; can describe behavior as detailed acts/processes, or results/functions

2. Applies theory of evolution by natural selection to behavior. Looks at similarities among species due to common ancestors and also differences in behavior/biology as a result of adaptation to different environment

3. Studying the way a particular behavior develops across the lifespan can give us a better idea of its function

4. To learn about biological mechanisms of an individual's behavior, must look at how present body works ONLY as machine made up of billions of neurons

Comment on the prevalence of psychiatric and neurological disorders in contemporary society, and discuss their economic and emotional impact.

1 in 5 people currently have a psychiatric and/or neurological disorder.

In US, most common neurological include: stroke, alzheimers, epilepsy

In US, most common psychiatric are anxiety disorders, attetion/impulse disorders, and mood disorders

1 in 4 people will have 2 or more psychiatric disorders in their life

Financial toll is enormous, more than corporal illness.

Can range in severity - from manageable to debilitating.

What kinds of research studies are done in order to learn about the biological basis of behavior

1. somatic intervention
2. behavioral intervention
3. correlation

somatic intervention

an approach to finding relations between body variables and behavioral variables that involves manipulating body structure or function and looking for resultant changes in behavior

physical alteration is the independent variable, while the behavioral effect is the dependent variable

examples of somatic intervention

Administering hormone to some animals but not others and comparing the later sexual behaviors of both groups

Electrically stimulating region of the brain and measuring alterations in movement

Destroying specific region of the brain and observing subsequent sleep changes

within-participants experiment

an experiment in which the same set of individuals is compared before and after an experimental manipulation. The experimental group thus serves as its own control group

control group

in research, a group of individuals that are identical to those in an experimental (or test) group in every way except that they do not receive the treatment/manipulation. The experimental group is then compared to the control group to assess the effect of the treatment.

between-participants experiment

An experiment in which an experimental group of individuals is compared with a control group that is identical in every way except that they did not receive the experimental treatment or manipulation. The control group is entirely separate.

behavioral intervention

An approach to finding relations between body and behavioral variables that involves intervening in the behavior of an organism and looking for resultant changes in body structure or function

behavior is the independent variable and change in body is dependent

can be within-group or between-group

examples of behavioral intervention

1. allowing adults of each sex to interact, and measuing subsequent changes in sex hormones

2. having a person perform a cognitive task while in a brain scanner, and measuring changes in activity in specific regions of the brain

3. training an animal to fear a previously neutral stimulus, and observing electrical changes in the brain that may encode newly learned association

correlation

the tendency of two measures to vary in concert, such that a change in one measure is matched by a change in another

measures how closely changes in one variable are associated with change in another

DOES NOT INFER CAUSATION

examples of correlational studies

1. observing the extent to which memory ability is associated with the size of a certain brain structure
2. noting that increases in a certain hormone are accompanied by increase in aggressive behavior

causality

the relation of cause and effect, such that we can conclude that an experimental manipulation has specifically caused an observed result

biological psychology research is guided by the underlying understanding that relationships between brain and body are

reciprocal: each affects the other in an ongoing cycle of bodily and behavioral interactions

a child can have half the brain removed and still develop normal intelligence

true

levels of analysis

the scope of experimental approaches. A scientist may try to understand behavior by monitoring molecules, nerve cells, brain regions, or social environments or using some combination of these levels of analysis

reductionism

the scientific strategy of breaking a system down into increasingly smaller parts in order to understand it