Neural Stimulation Techniques & Behavioral Genetics in Psychology

What is stimulating neural activity?

A group of techniques that allow researchers to artificially change the neural activity of a specific brain region.

Why is stimulating neural activity important?

It allows investigation of the functions of a certain brain region by manipulating its activity.

What is electrical stimulation in neural activity?

Implanting a wire in the brain to pass electric currents, providing low spatial resolution but high temporal resolution.

What is chemical stimulation?

Implanting a cannula in the brain to inject excitatory amino acids, offering low spatial and temporal resolution.

What is optogenetics?

A method to stimulate specific types of neurons in particular brain regions using light, providing high spatial and temporal resolution.

What is transcranial magnetic stimulation (TMS)?

A non-invasive technique using magnetic fields to stimulate neurons, allowing for excitation or interference with brain functions.

What is behavioral genetics?

The study of the genetic basis of behavior, exploring the link between genetics and mental health issues.

What are the main methods of behavioral genetic research?

Family studies, twin studies, adoption studies, and molecular genetics.

What is the difference between monozygotic and dizygotic twins?

Monozygotic twins share 100% of their genes, while dizygotic twins share only 50%.

What do adoption studies aim to determine?

They aim to rule out environmental impacts by comparing similarities between adopted children and their biological versus adoptive parents.

What is the significance of a concordance rate in twin studies?

It measures the likelihood that both twins share a trait, indicating a genetic predisposition.

What is the role of neurotransmission in the nervous system?

It involves the release of neurotransmitters across the synaptic cleft, facilitating communication between neurons.

What are agonists and antagonists in the context of drugs?

Agonists activate receptors, while antagonists block receptors from becoming active.

How does cocaine affect neurotransmission?

It blocks dopamine transporters, increasing dopamine levels in the synapse.

What is the action of amphetamines on neurotransmission?

They reverse dopamine transporter function, increasing extracellular levels of monoamines.

What are some examples of amphetamines used for ADD and ADHD?

Adderall, Ritalin, and Dexedrine, which increase activity in the prefrontal cortex.

What characterizes drug addiction?

It is a biological disorder marked by compulsive drug use, loss of control, and negative emotional states when access is prevented.

What is the impact of drugs on the nervous system?

They can affect receptors, ion channels, DNA, nuclear receptors, and enzymes involved in neurotransmission.

What is the role of calcium ions (Ca2+) in neurotransmission?

They signal vesicles to release neurotransmitters by exocytosis when action potentials arrive at the axon terminal.

What is the definition of a drug according to Write & Montag (1949)?

A substance or mixture of substances found to have therapeutic value for treating human diseases.

What is the significance of the phrase 'Your genes + Your environment & lifestyle = YOU!'?

It emphasizes the interaction between genetic predispositions and environmental influences on behavior.

What does the term 'drug dependence' refer to?

It refers to the emergence of negative emotional states when access to the drug is prevented.

What is the primary function of drugs that affect the nervous system?

They modulate chemical synaptic transmission.

What determines how a drug affects brain function and behavior?

The brain circuit and type of neurotransmitter involved.

What is homeostasis?

The process by which the body's substances and characteristics are maintained at their optimal level.

What is a system variable in a regulatory mechanism?

A variable controlled by a regulatory mechanism.

What is the set point in a regulatory mechanism?

The optimal value of the system variable.

What role does a detector play in a regulatory mechanism?

It signals when the system variable deviates from the set point.

What is a correctional mechanism?

A mechanism capable of changing the value of the system variable.

What is negative feedback?

A process whereby the effect produced by an action serves to diminish or terminate that action.

What triggers the drinking behavior in response to water loss?

Detectors signal the loss of water, prompting drinking as a correctional mechanism.

What are the two types of thirst?

Osmometric thirst and hypovolemic thirst.

What causes osmometric thirst?

An increase in the osmotic pressure of the interstitial fluid relative to the intracellular fluid.

Where are most osmoreceptors located?

In the OVLT (organum vasculosum of the lamina terminalis).

What is vasopressin and its role in water balance?

A hormone that raises blood pressure and enables the kidneys to reabsorb water.

What is angiotensin II and its effects?

A peptide hormone that constricts blood vessels, retains sodium and water, and produces thirst.

What is the role of the Median Pre-optic Nucleus in drinking behavior?

It integrates signals from the OVLT, SFO, and nucleus of the solitary tract to drive drinking behavior.

What initiates a meal according to metabolic signals?

Glucoprivation and lipoprivation signal a dramatic fall in glucose and fatty acids available to cells.

What is the function of leptin?

A hormone secreted by adipose tissue that may be involved in long-term satiety.

How does the lateral hypothalamus (LH) influence hunger?

It regulates hunger, while the arcuate nucleus controls how the LH responds.

What is the role of NPY neurons in hunger and satiety?

Excitation of NPY neurons indicates hunger, while their inhibition along with excitation of CART neurons indicates satiety.

What is the effect of high insulin levels during a meal?

They generally decrease appetite.

What is ghrelin and its effect on hunger?

A hormone that stimulates hunger, with levels increasing before a meal.

What happens to the body fluids when drinking occurs?

Water is absorbed, leading to the normalization of body fluids.

What is the role of stretch receptors in the stomach?

They sense distension and send signals to the brain to indicate satiety.

What is the function of CCK (cholecystokinin) in eating?

It reduces gastric emptying and promotes satiety.