Brain and Behavior

what does the biological approach argue?

that there are physiological origins of many behaviors and humans should also be studied biologically. the relationship between bio factors and behavior is bidirectional.

what is the most basic assumption the biological approach makes?

that there are biological correlates of behavior (complex human behaviors have physiological origins). those correlates include neurotransmitters, hormones, brain structure, and genetics.

what is the second assumption the biological approach makes?

that behaviors can be inherited, however it is argued that there is not a single gene per behavior but rather a combo of gene expression that may lead to physiological processes that result in a behavior.

what is the final assumption the biological approach makes?

that animal research can provide insight into human behavior. our nervous system and endocrine systems work a lot like other mammals and our genetic makeup is similar to animals.

what is the interactionist approach?

uses the three approaches to psychology (biological, cognitive, and sociocultural)

what is the reductionist approach?

the approach that analyzes a complex behavior by studying the simplest mechanisms believed to be possible

what is one of the most common ways to study the brain before modern scanning technology? describe.

case studies. case studies are often holistic. they use triangulation. however, they have limitations

• they do not and cannot manipulate the independent variable and no cause-and-effect relationship can be determined

• case studies are of only single individuals

• it cannot be replicated

• it may be difficult to verify information about the patient before the accident took place

psychologists do not use a single case study to draw definitive conclusions about the role of the brain on behavior

what are the types of triangulation in case studies?

data triangulation, method triangulation, researcher triangulation, theory triangulation

discuss magnetic resonance imaging (mri)

an mri scanner uses a magnetic field and radio waves to map the activity of hydrogen molecules. can be either viewed as a slice of the brain from any angle or used to create a 3d image of the brain.

what are the advantages and limitations of using an mri scan?

• the procedure is non-invasive and the image has high resolution

• however, it only indicates structure and does not map what is happening in the brain

discuss positron emission tomography (pet)

pet is used to observe metabolic processes in the brain by detecting the gamma rays emitted indirectly by a tracer. it is based on the assumption that areas of high radioactivity are associated with brain activity.

how do pet scans work?

before a pet scan begins, a patient is given a safe dose of a radioactive tracer compound introduced into the body by a modified glucose molecule (fdg), which then enters the bloodstream, where it can travel to the brain. if a particular area of the brain is more active, more glucose will be needed there. when more glucose is used, the radioactive tracer is detected by the pet scanner. the scan takes between 30 minutes and two hours and produces a multi-colored image showing which the most active parts of the brain. the color of each dot shows the intensity of the energy signal.

what are the advantages and limitations of using a pet scan?

• it allows participants to perform psychological tasks while the researcher observes brain activity

• however it requires an injection with a small amount of radioactive material

• additionally, pet scanning is quite slow and has relatively poor resolution

discuss functional magnetic image resonance imaging (fmri)

it shows actual brain activity and indicates which areas of the brain are active when engaged in a behavior or cognitive process. it measures changes in blood flow and oxygen level in the active brain as a measurement of neural activity and is one of the most frequently used technologies in biopsychological research. when a specific brain area is active and uses more oxygen, therefore increasing blood flow.

what are the advantages and limitations of fmris?

• it shows actual brain activity

• it is non-invasive, no radioactive isotope is necessary

• the quality is also much better

• demonstrates changes in the brain over the period of the scan

what are the limitations of brain-imaging techniques?

• not a natural environment for cognition and research may lack ecological validity

• artifacts (unintended distortions or biases) in the imaging because the brain activity may be related to a reaction to the machine rather than the behavior

• the use of colors may exaggerate the activity

• brain areas activate for various reasons, it might not be because of the stimuli

what is localization of function?

the theory that specific parts of the brain are responsible for specific behaviors or cognitive processes.

what is distributive processing?

the theory that several parts of the brain have to work together. this is what is argued in memory research.

what is equipotentiality?

the theory that the brain is able to transfer functional memory from a damaged part of the brain to other undamaged parts

relative localization

the theory that while one part of the brain may play a key role in a behavior, several parts of the brain may play a lesser role

strict localization

the theory that only a single area of the brain is responsible for a behavior

what are the four key areas in the brain?

brain stem, cerebellum, cerebrum, and limbic system

describe the cerebellum

brain region at the back of the head, just above the brainstem

what is the cerebellum responsible for?

coordinating voluntary movements, maintaining balance and posture, and fine-tuning motor skills

additionally: cognitive functions such as attention, language processing, and emotional regulation

describe the brainstem

essential part of the cns that connects the brain to the spinal cord

consists of three main parts: the midbrain, pons, and medulla oblongata

what is the brainstem responsible for?

regulating many involuntary functions such as breathing, heart rate, blood pressure, and reflexes like swallowing and coughing

describe the cerebrum

the largest part of the brain, first divided into two hemispheres (left and right) and then lobes

what is the cerebrum responsible for?

higher brain functions such as thinking, reasoning, memory, and voluntary muscle movements

what is the frontal lobe associated with?

executive functions (planning, decision-making, and speech)

describe the limbic system

often referred to as the emotional brain, a major focus of psychological research for its role in memory and emotion

what are the key components of the limbic system?

amygdala, basal ganglia, hippocampus, hypothalamus, nucleus accumbens

define plasticity

the brain’s ability to alter its own structure after changes within the body or in the external environment

not only can the brain determine and change behavior, but behavior and environment can change the brain

define brain plasticity

the brain’s ability to change its neural structures to adapt to changes that occur in the structure of the brain due to learnings, experiences, or changes within the body or external environment

define dendritic branching

when we learn something new and the neurons connect to create a new trace in the brain

the dendrites grow in numbers and connect with other neurons

what is a synapse?

the space between neurons where they communicate with each other

what is synaptic plasticity?

refers to how synaptic connections can change over time, “use it or lose it”

what is long-term potentiation?

when synapses become stronger through repeated use.

what is synaptic pruning?

when a synapse is not used or under-stimulated, the brain removes them

what are neurons?

nerve cells, one of the building blocks of behavior. they send electrochemical messages to the brain so that people can respond to stimuli.

what is neurotransmission?

the process by which electrochemical messages from the neuron are sent to the brain.

define action potential

the electrical impulse that travels along the body of the neuron

what is a neurotransmitter?

natural chemical messengers that transmit info from one neuron to another

what is the path of an action potential?

1. an action potential travels down the axon

2. the AP releases neurotransmitters stored in the terminal buttons into the synapse

3. the neurotransmitters cross the synapse then fit into receptor sites

4. once the message is passed on, the neurotransmitters are either broken down by an enzyme or undergo reuptake (they are reabsorbed by the terminal buttons)

what are the types of neurotransmitters?

excitatory neurotransmitters, inhibitory neurotransmitters, metabotropic neurotransmitters

give at least one example of a neurotransmitter and its purpose

possible answers:

acetylcholine (excitatory)

• role in consolidation of memory in the hippocampus

dopamine (metabotropic)

• controls brain’s reward and pleasure centers

• key role in motivatiorn, low levels are linked to addictive behavior

norepinephrine (metabotropic

• arousal and alertness

serotonin (metabotropic)

• sleep, arousal levels, and emotion

gamma-aminabutyric acid (GABA) (inhibitory)

• helps create new memories

what are agonists and antagonists?

agonists

• activates a receptor

• endogenous agonists are biologically part of the body

• exogenous agonists are external to our system

antagonists

• blocks a receptor

define data triangulation

when more than one source of data is used

define method triangulation

when more than one research method is used

define theory triangulation

when we look at a case from more than one theoretical perspective

define researcher triangulation

when more than one researcher studies a case

what is the occipital lobe associated with?

visual processing

what is the parietal lobe associated with?

perception of stimuli

what is the temporal lobe associated with?

auditory processing and memory

what do excitatory neurotransmitters do?

increase the likelihood of a neuron firing by depolarizing it

what do inhibitory neurotransmitters do?

decrease the likelihood of a neuron firing by hyperpolarizing it

what do metabotropic neurotransmitters do?

affect the neuron indirectly and are neither inhibitory or excitatory

what does the amygdala (mostly) do?

role in the formation of emotional memory and fear responses

what does the basal ganglia (mostly) do?

role in forming habits and procedural memory

what does the hippocampus (mostly) do?

responsible for the transfer from stm to ltm

what does the hypothalamus (mostly) do?

involved in homeostasis, hunger, thirst, emotion, circadian rhythms, and control of the autonomic nervous system (part of the nervous system that regulates involuntary physiologic processes)

what does the nucleus accumbens (mostly) do?

plays a role in addiction and motivation

what is short-term memory?

a limited capacity memory system where information is held for a brief period

what is long-term memory?

the relatively permanent storage of information, skills, and experiences