19. Gene And Behaviour

Question 1

Explain about the brain region related to Language

Answer 1

• Broca’s area: located in the frontal lobe, is responsible for speech production and grammatical processing. (Damage to this area causes Broca’s aphasia, characterized by slow and effortful speech.)
• Wernicke’s area :in the temporal lobe is responsible for language comprehension, and damage leads to fluent but meaningless speech known as Wernicke’s aphasia
• ** The planum temporale**, located near Wernicke’s area, plays an important role in processing speech sounds and is typically larger in the left hemisphere.

Question 2

What is the gene of faithfulness

Answer 2

AVPR1a Gene -(Arginin) vasopressin receptor
monogamous

Question 3

Which psychological school was led by Sigmund Freud and emphasized unconscious desires and sexual instincts? 1. Functionalism 2. Behaviorism 3. Psychoanalytic school 4. Ethology 5. Cognitive psychology

Answer 3

3. Psychoanalytic school (Freud redefined sexual desire as a primary motivational energy and focused on unconscious insight.)

Question 4

Who is associated with ‘Functionalism’ and believed that humans have more instincts than animals? 1. Ivan Pavlov 2. William James 3. James Watson 4. E.O. Wilson 5. Noam Chomsky

Answer 4

2. William James (He believed instincts were of evolutionary origin and central to human behavior.)

Question 5

Which school of thought views the brain as a ‘blank slate’ and emphasizes learning over instincts? 1. Sociobiology 2. Behaviorism 3. Cognitive psychology 4. Ethology 5. Evolutionary psychology

Answer 5

2. Behaviorism (Pavlov and Watson argued that environment and learning are the primary determinants of behavior.)

Question 6

Which gene is known as the ‘Adventure gene’ or linked to novelty seeking and risk-taking? 1. CHRM2 2. VMAT2 3. FoxP2 4. Drd4 (Ddr4-R7 variant) 5. HTR2B

Answer 6

4. Drd4 / Ddr4-R7 (The 7R variant is associated with novelty seeking, risk-taking, and even liberal political views.)

Question 7

The AVPR1a gene (arginine vasopressin receptor) is associated with which behavioral trait in Prairie Voles? 1. Aggression 2. Intelligence 3. Monogamy/Faithfulness 4. Speech 5. Addiction

Answer 7

3. Monogamy/Faithfulness (Long alleles of the AVPR1a promoter lead to higher receptor density and pair-bonding behavior.)

Question 8

Which axis is responsible for the body’s hormonal response to stress? 1. HPA axis 2. NO synthase pathway 3. Serotonin transporter system 4. cAMP pathway 5. Dopamine reward pathway

Answer 8

1. HPA axis (Hypothalamus-Pituitary-Adrenal axis releases cortisol in response to stress.)

Question 9

A point mutation in the FoxP2 gene in humans leads to difficulties in: 1. Memory 2. Aggression control 3. Speech and grammar 4. Religious belief 5. Social dominance

Answer 9

3. Speech and grammar (FoxP2 is essential for the development of proper articulation and language structures.)

Question 10

Individuals with the ‘short allele’ of the Serotonin Transporter (SERT) gene are more likely to exhibit: 1. Lower anxiety 2. Higher neuroticism and anxiety 3. Higher intelligence 4. Increased ruthlessness 5. Monogamous behavior

Answer 10

2. Higher neuroticism and anxiety (The short allele results in lower SERT expression and is linked to negative thinking.)

Question 11

Which enzyme is responsible for the degradation of monoamines like serotonin and dopamine? 1. NO synthase 2. COMT 3. MAO (Monoamine-oxidase) 4. Adenylate cyclase 5. Protein Kinase A

Answer 11

3. MAO (Monoamine-oxidase) (It breaks down neurotransmitters; its deficiency is linked to aggression.)

Question 12

The COMT gene (catechol-O-methyl transferase) affects behavior by: 1. Producing Nitric Oxide 2. Degrading dopamine in the prefrontal cortex 3. Transporting vasopressin 4. Regulating the HPA axis 5. Encoding speech proteins

Answer 12

2. Degrading dopamine in the prefrontal cortex (The Val/Met polymorphism affects enzyme activity and cognitive/anxiety levels.)

Question 13

Define the Psychoanalytic school of Sigmund Freud.

Answer 13

A school of psychology that emphasizes the influence of the unconscious mind on behavior, focusing on sexual and life-saving instincts as primary motivators.

Question 14

What is William James’s concept of Functionalism?

Answer 14

A theory that mental states and behaviors are functional adaptations that have evolved to help humans survive in their environment.

Question 15

Explain the core belief of Behaviorism.

Answer 15

The belief that behavior is learned through interaction with the environment (conditioning) and that innate instincts are not the primary drivers of behavior (‘blank slate’).

Question 16

How does Cognitive Psychology differ from Behaviorism?

Answer 16

Cognitive psychology rejects the ‘black box’ view of the brain; it uses psychological methods to examine internal mental processes like memory, problem-solving, and language.

Question 17

Define Sociology in the context of behavior.

Answer 17

The study of human social behavior, origins, development, organizations, and institutions, specifically focusing on groups and cultures.

Question 18

What is the focus of Social Psychology?

Answer 18

It investigates how the thoughts, feelings, and behaviors of individuals are influenced by the actual, imagined, or implied presence of others, often using psychological methods.

Question 19

Define Ethology.

Answer 19

The scientific study of animal behavior, usually in natural conditions, viewing behavior as an evolutionary adaptive trait (e.g., Fixed Action Patterns).

Question 20

Explain the perspective of Sociobiology.

Answer 20

A field of biology that aims to examine and explain social behavior in terms of evolution (pioneered by E.O. Wilson).

Question 21

What is Evolutionary Psychology?

Answer 21

A theoretical approach that examines mental and psychological traits—such as memory, perception, or language—as adaptations (i.e., as the functional products of natural selection).

Question 22

Describe the flow of the HPA axis during a stress response.

Answer 22

The Hypothalamus releases CRH (Corticotropin-releasing hormone) -> the Pituitary gland releases ACTH (Adrenocorticotropic hormone) -> the Adrenal cortex releases Cortisol.

Question 23

What is the function of the Amygdala in behavior?

Answer 23

It is the integrative center for emotions, emotional behavior, and motivation, particularly associated with fear and emotional processing.

Question 24

What is the role of the Hippocampus?

Answer 24

It is primarily associated with memory, specifically the formation of new memories and spatial navigation.

Question 25

What is the role of the Hypothalamus in the brain?

Answer 25

It links the nervous system to the endocrine system via the pituitary gland and regulates homeostasis (hunger, thirst, sleep, stress response).

Question 26

What is the CHRM2 gene associated with?

Answer 26

It is known as a 'gene of intelligence' or cognitive function; variations are linked to performance in intelligence tests.

Question 27

Explain the role of the Drd4 gene (Dopamine receptor D4).

Answer 27

It encodes a dopamine receptor. Certain variants (like the 7R allele) are linked to novelty seeking, risk-taking, and unfaithfulness (the 'adventure gene').

Question 28

What behavior is associated with the VMAT2 gene?

Answer 28

It is associated with religious or spiritual belief, sometimes referred to as the 'God gene,' as it regulates monoamine transport.

Question 29

What is the significance of the FoxP2 gene?

Answer 29

It is the 'gene of speech.' Mutations cause severe speech and language disorders. It has seen two significant amino acid changes in the last 200,000 years of human evolution.

Question 30

Describe the behavior linked to the HTR2B gene (Q20* allele).

Answer 30

Linked to extreme impulsivity and novelty seeking, particularly when combined with alcohol consumption (found in studies of Finnish prisoners).

Question 31

What is the 'Xq28' region associated with?

Answer 31

It is a region on the X chromosome linked to the genetics of male homosexuality (the 'gay gene' study).

Question 32

Define Social Darwinism.

Answer 32

A sociological theory that applies the 'survival of the fittest' concept to human societies, often used to justify social inequality.

Question 33

What is Eugenics?

Answer 33

A set of beliefs and practices aimed at improving the genetic quality of a human population, often through selective breeding or sterilization (pioneered by Francis Galton).

Question 34

What is the function of Monoamine-oxidase (MAO)?

Answer 34

It is an enzyme that degrades monoamine neurotransmitters (serotonin, dopamine, norepinephrine) in the synapse.

Question 35

What is the role of the Serotonin Transporter (SERT)?

Answer 35

It regulates the intensity and duration of serotonin signaling by transporting serotonin from the synaptic cleft back into the presynaptic neuron.

Question 36

Explain the biological consequence of the MAO-A gene 'low-activity' variant.

Answer 36

When combined with childhood maltreatment, it leads to a significantly increased risk of aggressive and anti-social behavior in adulthood (Brunner syndrome).

Question 37

How does NO synthase (Nitric Oxide synthase) affect aggression?

Answer 37

NO acts as a gaseous neurotransmitter. Knockout mice lacking the nNOS gene show a massive increase in aggressive behavior.

Question 38

What is the relationship between Testosterone and behavior?

Answer 38

High levels of testosterone are biologically linked to increased aggression, social dominance, and competitive behavior.

Question 39

What does the grb10 gene regulate?

Answer 39

It is associated with social dominance; mutations or changes in expression can affect an individual's position in a social hierarchy.

Question 40

Explain the Val/Met polymorphism of the COMT gene.

Answer 40

The 'Val' allele results in 4x higher enzyme activity (low dopamine, low anxiety, low focus). The 'Met' allele results in low activity (high dopamine, high anxiety, high focus).

Question 41

Define 'Addiction' from a biological perspective.

Answer 41

A chronic brain disorder characterized by compulsive engagement in rewarding stimuli, despite adverse consequences, involving the dopamine reward pathway.

Question 42

What is the role of the Ddr2 gene (Dopamine receptor D2) in addiction?

Answer 42

Low levels or specific variants of D2 receptors are often found in individuals with addictive behaviors, as they may seek external stimuli to compensate for a low internal reward signal.

Question 43

How does the AVPR1a gene relate to 'Ruthlessness' in humans?

Answer 43

In the 'Dictator Game' study, individuals with shorter AVPR1a promoter alleles were found to be more 'ruthless' (less altruistic/generous) in money allocation.

Question 44

Explain the significance of the Ddr4-R7 variant in 'Novelty Seeking'.

Answer 44

The 7R variant is less sensitive to dopamine, leading individuals to seek higher levels of stimulation (risk-taking, new experiences) to achieve a reward sensation.

Question 45

What is the 'Nature vs. Nurture' debate?

Answer 45

The debate concerning whether human behavior is determined by biological genetics (Nature) or environmental upbringing and experience (Nurture).

Question 46

Describe the 'fertile female' hypothesis in homosexuality.

Answer 46

A hypothesis suggesting that genes for male homosexuality may persist because they increase the fertility of female relatives who carry them.

Question 47

What are the components of the brain's 'Reward Pathway'?

Answer 47

The Ventral Tegmental Area (VTA) and the Nucleus Accumbens, primarily using dopamine as the signaling molecule.

Question 48

How does the HPA axis relate to the Amygdala?

Answer 48

The Amygdala can activate the HPA axis in response to fear, triggering the release of stress hormones.

Question 49

What is the effect of the 'short' vs 'long' allele in the AVPR1a gene promoter?

Answer 49

The long allele is associated with higher levels of vasopressin receptors and increased social bonding/faithfulness (in voles and humans).

Question 50

Explain the biological mechanism of addiction regarding the VTA.

Answer 50

The VTA (Ventral Tegmental Area) releases dopamine into the Nucleus Accumbens in response to rewarding stimuli, reinforcing the behavior.

Question 51

What is the 'One gene, one behavior' paradigm problem?

Answer 51

The oversimplified idea that a single gene controls a complex behavior, whereas most behaviors are polygenic and influenced by the environment.

Question 52

How does the COMT gene affect hesitation and anxiety?

Answer 52

The 'Met' allele (low enzyme activity) leads to higher dopamine levels, which can cause 'over-thinking,' higher anxiety, and hesitation, despite better cognitive concentration.