Meaning: 'Monitored' means to observe and check the progress or quality of something over a period of time, in this case, brain activity.

Wrong options:

• glanced: 'Glanced' implies a quick look, which does not convey the thorough observation required in this context.
• entertained: 'Entertained' suggests providing amusement, which is unrelated to the scientific observation of brain activity.
• involved: 'Involved' implies participation or engagement, but does not accurately describe the act of observing brain activity.

Correct answer: outermost

Explanation: The word 'outermost' correctly describes the layer of the brain, indicating it is the furthest from the center. It fits grammatically and contextually as it specifies the layer being discussed.

Meaning: 'Outermost' means the layer that is farthest away from the center, in this case, referring to the brain's outer layer.

Wrong options:

• outlandish: 'Outlandish' means bizarre or strange, which does not describe a layer of the brain.
• outgoing: 'Outgoing' refers to a personality trait of being sociable, which is not relevant to describing a brain layer.
• outside: 'Outside' is a general term that does not specifically indicate the layer's position relative to the brain's structure.

Correct answer: while

Explanation: The word 'while' serves as a conjunction that indicates simultaneous actions, fitting grammatically and contextually to show that both activities occurred at the same time.

Meaning: 'While' means during the time that; it indicates that the left hemisphere was active at the same time as the participants understood the jokes.

Wrong options:

• due to: 'Due to' indicates a reason, which does not fit the context of simultaneous actions.
• rather than: 'Rather than' suggests a choice between two alternatives, which is not applicable here.
• yet: 'Yet' implies contrast or an unexpected outcome, which does not align with the simultaneous nature of the actions described.

Correct answer: diagnosis

Explanation: The term 'diagnosis' fits grammatically and contextually as it refers to the identification of conditions affecting humor perception, aligning with the medical context of the sentence.

Meaning: 'Diagnosis' means the identification of the nature of an illness or other problem, particularly in a medical context.

Wrong options:

• execution: 'Execution' refers to carrying out a plan or action, which does not relate to identifying medical conditions.
• format: 'Format' refers to the arrangement or organization of something, which is not relevant to the context of medical conditions.
• strategy: 'Strategy' implies a plan of action, which does not specifically address the identification of conditions affecting humor perception.