Biological Psychology: Reductionism, Holism, Genes, Neurons, and Neuroimaging

A set of question-and-answer flashcards covering reductionism, epigenetics, genotype/phenotype, genetics, the nervous system, neuron structure and function, neurotransmitters, glial cells, autonomic nervous system, and neuroimaging concepts.

What is a reductionistic approach in psychology?

Breaking down complex behavior into its simplest components for study.

What are epigenetic models?

Models showing how environment can turn genes on or off through gene switches, without changing the DNA sequence.

Define genotype.

An organism's complete genetic makeup, its body's instruction manual.

Define phenotype.

The observable traits that result from the genotype interacting with the environment.

How many chromosome pairs do humans have?

23 pairs (46 total).

What did the Human Genome Project reveal about the number of genes?

Approximately 25,000 genes coding for various proteins.

What was discovered about 'junk DNA'?

Extra DNA sequences are gene switches that regulate when genes are turned on or off.

How can the environment affect genetic expression?

By epigenetic factors such as stress or extreme conditions that turn genes on or off.

What is obesity heritability?

About 45%.

Why is the heritability concept considered less central now?

Because environment interacts with genetics; genes can be turned on/off by conditions, making nature vs nurture more intertwined.

What is an evolutionary model?

A model that studies behaviors that improve survival and reproduction, passing on genes.

Explain goosebumps in evolutionary terms.

A vestigial response in humans; hair stands to look bigger and insulate; originally aided survival in fur-bearing ancestors.

What is the biopsychosocial model?

A holistic approach acknowledging biological, psychological, and social factors together determine health and behavior.

CNS stands for and what are its two main structures?

Central nervous system; brain and spinal cord.

What are the two main kinds of cells in the CNS?

Neurons and glial cells.

What are dendrites and dendritic spines?

Dendrites receive information; dendritic spines are small protrusions that receive inputs; more dendrites/spines mean more input.

What is the soma?

The neuron's cell body containing nucleus and organelles.

What is the axon?

The long projection that sends signals to the next neuron or effector.

Name the three basic neuron types.

Sensory neurons, motor neurons, and interneurons.

What are mirror neurons?

Neurons that simulate the states of others, supporting empathy and understanding others' actions.

What is resting potential?

The baseline electrical charge of a neuron when at rest.

What is an action potential?

The all-or-none electric impulse that travels along the axon.

Explain the all-or-none law.

Once threshold is reached, the neuron fires with a uniform strength; it either fires or not.

What is the refractory period?

A brief period after firing when the neuron cannot fire again.

What is myelin and what is its effect?

A fatty sheath around some axons that speeds transmission along the axon.

What is the difference between excitatory and inhibitory neurotransmitters?

Excitatory increase the likelihood of the next neuron firing; inhibitory decrease it.

Name some major neurotransmitters and the endogenous painkiller.

Dopamine, serotonin, norepinephrine; endorphins are the body's own painkillers (endogenous opioids).

What are glial cells and their role?

Support neurons, insulate with myelin, modulate neuronal responses, and assist in other functions.

What is the peripheral nervous system composed of?

The somatic nervous system and the autonomic nervous system.

What are the sympathetic and parasympathetic divisions?

Sympathetic: fight or flight; Parasympathetic: rest and digest; they balance each other in what is called sympathetic tone.