bio approach ERQ/SAQ - NOT EVOLUTION

localization of function, neuroplasticity, neurotransmission, brain imaging technologies, hormones, pheromones

brain imaging techniques

Technologies used in psychology to study brain structure, function, damage, and support prior findings. The results of BITs are usually correlational and Difficult to establish causation, but are Continually evolving.

Magnetic resonance imaging

shows density (grey matter) and mass. uses a magnetic field and radio waves to map the activity of hydrogen molecules, which are present in different brain tissue to different degrees. Structure only. Can be a 2D slice of the brain or compiled into 3D pics

non invasive, has no radiation, can be repeated, however, it only shows the structure

The data from MRIs are measured using Voxel-based morphometry and pixel counting. VBM measures the difference in density of grey matter in the brain and Pixel counting counts the pixels in the MRI images to calculate the area of the parts of the brain.

what is localization of function

the idea that specific parts of our brain are linked to specific behavior

hippocampus

small structure located in the brain’s temporal lobe. It involves forming, organizing, and storing memories. It transfers information from short-term memory to long-term memory.

The anterior hippocampus is primarily involved in encoding and retrieving abstract or general memories, while the posterior hippocampus focuses on specific, detailed memories, especially spatial and contextual ones

it is a key part of the limbic system, which is associated with emotion and motivation.

neuroplasticity and causes

Neuroplasticity is the brain's ability to change and adapt the connections between neurons. it is caused by Both the environment and genetics, normal development, learning/experience/practice, and Damage or disease.

Dendritic branching and pruning

neuroplasticity involves long-term potentiation, which is the strengthening of synapses due to the repetition of a task. This leads to dendritic branching, which increases neural density. Conversely, A lack of potentiation may lead to neural pruning, where extra neurons and synaptic connections are eliminated

The brain has a lifelong ability to reorganize itself by forming new neural connections and pruning old ones that are no longer required.

Neuroplasticity and injury

Neuroplasticity also means that the brain can compensate for injury and “rewire” itself as required to ensure that it continues to function properly.

acetylcholine

One neutotrasmitter that has an effect on behavior is Acetylcholine (ACh), which plays a role in the consolidation of memory in the hippocampus.

neurons

neurons are specialized cells in the nervous system that transmit information through electrical and chemical signals.

They communicate with each other across small gaps called synapses by releasing neurotransmitters, which are chemical messengers. Neurons have three main parts: the dendrites (which receive signals), the cell body (which processes the information), and the axon (which sends signals to other neurons, muscles, or glands). This transferral of messages is known as neurotransmission. during neurotransmission, An action potential releases neurotransmitters into the synaptic gap between the neurons.

excitatory vs inhibitory, reuptake, agonist vs antagonist

Neurotransmitters can be excitatory (speeds up neurotransmission) or inhibitory (slows it down). Once the message is passed on, the neurotransmitters are either broken down or reabsorbed, a process called re-uptake.

Neurotransmission also involves agonists and antagonists. Agonists are chemicals that activate a receptor to produce a biological response. Every neurotransmitter is an agonist. ACh is an excitatory agonist. Antagonists are chemicals that decrease the effect of the neurotransmitter. In studying neurotransmission, Antagonists are often used to stop neurotransmitters to see the effect on behavior

hormones

Chemical messengers that start/stops behavior such as Growth, reproduction, mood, energy. they are produced and secreted by glands in the endocrine system.

glands that secrete hormones

pituitary gland: controls the activity of other glands.

adrenal glands: regulates response to fear/stress.

Hypothalamus gland: controls essential bodily functions like hunger, thirst, temperature, and hormone release

how hormones work

The brain gets a stimuli, sends a message to the pituitary gland, which sends a message to another gland to release a hormone. Hormone is released in bloodstream and only binds with specific cell receptors (lock and key).

Because they are carried by cells in the bloodstream they are slower but linger longer

When the brain sends a signal to stop, hormone secretion stops

Cortisol (stress hormone)

• Helps the body respond to stress. Increases the metabolism of sugar in the bloodstream to provide energy and curbs non-essential functions.

• Released from adrenal glands.

• Lots of cells with cortisol receptors

• Too much cortisol for prolonged periods is linked with impaired memory 

Oxytocin trust hormone

• Produced by the hypothalamus and secreted by the pituitary gland.

• When it affects the brain, it acts as a neurotransmitter

• believed to play a role in social bonding and trust between people.

pheromones

Chemical substance produced by animals that stimulates others of the same species. They are secreted through glands to act outside the body.

In humans, there is some evidence of primer pheromones which cause slow, long-term physiological changes. however, there is substantial research disproving its effects.

potential pheromones

Androstadienone (AND) found in male semen and sweat, associated with masculinity. Estratetraenol (EST), which is found in female urine, associated with femininity. both influence the perceptions of gender and can enhance attraction to others.

genes inheretence

the process by which genes (segments of DNA) are passed from parent to offspring. genes can be responsible for the development of some behavioral and physical characteristics.

Alleles are variants of genes. 1 allele from each parent is inherited. Mutations of genes can occur, which is a change in DNA sequence.

5-HTT gene

One gene that influences behavior is the 5-HHT gene. Also known as the serotonin transporter gene, plays a key role in the regulation of serotonin levels in the brain by coding for a protein that is involved in the reuptake of serotonin.

It has two main alleles: a short allele and a long allele. The short allele is a mutation that results in reduced efficiency of serotonin reuptake. This lower serotonin activity has been associated with higher risks of depression.

diathesis stress model

Diathesis-Stress Model says that the risk for depression increases for everyone as the number of stressful life events increases. However, depending on which 5HTT gene you inherit, your risk may become greater than other people experiencing the same number of stressful events. 

genetic similarities

Studying genetic similarities helps scientists quantify genetic and environmental factors that increase the risk of disorders/diseases.

family studies

look at the concordance rate —the likelihood both twins show the trait— of a behavior within a family across generations