Explanation​:

Stress hormones such as adrenaline and cortisol released after an event activates the amygdala often linked to the formation of flashbulb memories.

Choices B, C and A are hormones but are not related to the amygdala.

Explanation​:
Split-brain studies represent research on brain lateralisation which is the division of functions between the two hemispheres of the cortex. Lateralization is a particular case of localization. Roger Sperry conducted initial animal research to understand this phenomenon.

Explanation​:

Answer A is incorrect because nonhuman animals can still be used for research and experimentation.

Answer B is incorrect because the experimenter and researcher need to have the appropriate licensure.

Answer C is incorrect because nonhuman animals can be used in a variety of settings and research methodologies.

Answer D is correct because all experimentation and research must comply with APA guidelines for ethical animal research.

Explanation​:

In neurological diseases, axons can regenerate or sprout in an attempt to reconnect with the target neuron and restore synapse function.

A is for synaptic plasticity, C is for synaptic pruning and D is about cortical remapping

Explanation​:

A transporter protein is a protein at a synapse that recognises neurotransmitter molecules and collects them to transport them somewhere (often back to the presynaptic neuron) where they can be degraded, recycled, or re-used. A, describes the process of neurotransmission, C, is the axon terminal and D, is the crossing of the synapse during neurotransmission.

Explanation​:

The biological approach in understanding human behaviour emphasises the role of genetics and other physiological factors in influencing personality and behaviour. Answers A, B, and C do not have this emphasis.

MRI scans use magnetic fields and radio waves to produce 3D computer-generated images. All metal objects and clothing on the body have to be removed before lying in the MRI machine. This is a disadvantage of the technique, as people with metallic implants cannot use this technique.

Explanation​:
The limbic system is an older subcortical structure of the brain. It is commonly called the “emotional brain” and includes several parts like the thalamus, hypothalamus, amygdala, and hippocampus. It is located on both sides of the thalamus, beneath the medial temporal lobe of the cerebrum.

It supports various functions such as emotion, behaviour and long-term memory.

Explanation​:
Phenotype is the set of traits that manifest in an individual's body, appearance, or behaviour. The set of traits as coded in an individual's DNA is called a genotype.

Phenotype comprises observable characteristics (eye colour, height) and unobservable characteristics (blood type, immune system). Genotype is the plan, and phenotype is the implementation of the plan.

Explanation​:

A, B and D are functions of the MRI and fMRI.

The difference between the MRI and fMRI is C, the ability to produce a video representation of brain activity over time, which a normal MRI cannot do.

MRI scans use magnetic fields and radio waves to produce 3D computer-generated images.

Explanation​:
Pheromones are chemical messengers used for communication among the same species. There is evidence for the existence of pheromones, and there is evidence that shows that pheromones don’t affect behaviour.

A few common critical evaluation points found in the research done for pheromones are - population validity, construct validity, ethics, demand characteristics as most research is for a self-selected sample, lack of internal validity due to the effect of extraneous variables, replicability because the nature of human behaviour is constantly changing.

Explanation​:
The amygdala is responsible for directing automatic or unconscious responses to emotional stimuli. It also plays a crucial role in linking sensory inputs with long-term memory in the cerebral cortex.

Additionally, the amygdala, together with the hippocampus, are both involved in emotion and cognition as they are central to processing emotion in relation to cognitive processes such as memory.

Explanation​:

Choice A is correct because fraternal twins only share 50% of their genes, and identical twins share 100%. Due to this, researchers can study the differences and similarities in personality, intellect, and behaviour.

Choices B, C, and D are incorrect because they do not address the nature aspect of the nature vs. nurture debate in twin studies.

Explanation​:
Twin studies aim to explore the interplay between genetics and the environment in shaping traits or behaviours. Researchers can discern the impact of genetics and environment on individual differences by comparing similarities between identical (monozygotic) and fraternal (dizygotic) twins. Kinship studies extend this investigation to non-twin relatives, investigating how traits vary across degrees of relatedness. These studies provide valuable insights into the complex interactions between genes and the environment in shaping human development and behaviour.

Explanation​:
The American Psychological Association (APA) documented the ethics of conducting animal research. Some of those include laboratory animals must be given humane care during and post experimentation, animal research proposals must be submitted to the Ethics Committee before the research, Animals reared in the laboratory must not be released into the wild as they may not be in a condition to protect themselves from other animals.

Explanation​:
Neurotransmitters are released from the presynaptic terminal of a neuron. The presynaptic terminal is the end of the axon, specifically the terminal bouton or synaptic knob, where the neuron forms synapses with other neurons or target cells. Once an action potential reaches the presynaptic terminal, neurotransmitters are released into the synaptic cleft, the small gap between the presynaptic neuron and the postsynaptic neuron or target cell. The neurotransmitters can bind to receptors on the postsynaptic neuron or target cell, transmitting the signal and facilitating communication between neurons.

Explanation​:
In the research by Antonova et al. in 2011, scopolamine (antagonist) blocks acetylcholine receptor sites. The research aimed to determine how blocking the acetylcholine receptors with scopolamine affects spatial memory.

The results showed that when participants were injected with scopolamine, they demonstrated a reduction in hippocampus activation compared to when they received a placebo.

Choice A (Ketanserin) is a 5-HT2 receptor antagonist, is a drug used clinically as an antihypertensive agent and in scientific research to study the serotonergic system. Liechti et al. (2000) research focuses on this antagonist.

Choice C (Psilocybin) is an agonist associated with antidepressant effects. Vollenweider et al (1998) research focuses on this agonist.

Choice D (Alcohol) is an agonist of GABA receptors. The body creates GABA from glutamate with the help of certain enzymes. Setiawan et al. (2013) have researched this agonist (the neurotransmitter affected is dopamine) focusing on mood changes.

Explanation​:
Hormones are chemical messengers released directly into the bloodstream by endocrine glands: adrenal glands, hypothalamus, pineal gland, pituitary gland, thyroid, parathyroid, thymus, pancreas, testes, and ovaries. These form the endocrine system.

Oxytocin is responsible for social bonding, affects trust in interpersonal interactions, and is referred to as the $\text{‘}$bonding hormone$\text{’}$ and $\text{‘}$love hormone$\text{’}$. It also helps to establish a strong bond between a mother and a child.

Explanation​:
Antagonists counteract neurotransmitters and prevent a signal from being passed further. It decreases the activation of a synaptic receptor by blocking the neurotransmitters from binding/bonding. An example of an antagonist is scopolamine, which affects the neurotransmitter Acetylcholine (ACh).

Explanation​:
The primary role of GABA (gamma-aminobutyric acid) is to send inhibitory signalling to the brain and reduce the effect of the excitatory neurotransmitter. It promotes relaxation by inhibiting the neurons from firing and balancing brain activity.

Explanation​:
De Dreu et al. (2010) have discovered that oxytocin, also called the love hormone, can lead humans to sacrifice themselves for the sake of their in-group members. Individuals were likely to self-sacrifice for the benefit of their in-group in a competition against the out-group.

The results showed that oxytocin was linked to in-group trust and cooperation, and aggression towards the members of the out-group.

De Dreu, C. K. W., Greer, L. L., Handgraaf, M. J. J., Shalvi, S., Van Kleef, G. A., Baas, M., Velden, F. S. T., Van Dijk, E., & Feith, S. W. W. (2010). The neuropeptide oxytocin regulates parochial altruism in intergroup conflict among humans. Science, 328(5984), 1408-1411. https<nolink>://doi.org/10.1126/science.1189047

Explanation​:

Choice A is incorrect because the researchers did the study with a clear and scientific purpose.

Choice B Is correct because the physical wellbeing of the monkeys was not taken into consideration, and thus resulted in harm and death to the animals.

Choice C is incorrect because the text does not make mention of the monkeys being acquired illegally or against regulation.

Choice D is incorrect because the study did not use the monkeys in a classroom or educational setting.

Explanation​:
The study done by Maguire et al. (2000) used an MRI scan to study the changes in the brain of taxi drivers in London.

They selected 16 taxi drivers and 50 non-taxi drivers for the study and scanned the brains of all the participants using the MRI. With the help of the MRI scan, they found that the posterior hippocampus was more prominent in taxi drivers compared to non-taxi drivers. The hippocampus is often associated with spatial memory - the ability to remember directions and places.

Explanation​:
Studying animal models refer to using animals in research to test a cause-effect hypothesis about a specific human behaviour—for example, understanding stress models, separation models, and medical models. They allow researchers to test hypotheses and explore interventions in a controlled and ethical manner.

Popular species commonly subjected to psychological research are rats, mice, pigeons, cats, rabbits, hamsters, dogs, chimpanzees, and baboons.