Biological theory of aggression

Question 1

What did sequencing in the Bruner study reveal?

Answer 1

It revealed the genetic abnormality to be a missense mutation resulting in a dysfunctional MAOA gene

Question 2

What did the Dutch males produce more of?

Answer 2

They produced dramatically raised levels of monoamines serotonin and noradrenalin as a result of a dysfunctional MAOA

Question 3

What did meta analysis of twin and adoption studies conclude about genetic factors?

Answer 3

They concluded that genetic factors account for between 40%-50% of the variance in aggressive behaviour

Question 4

What does the 40-50% variance suggest?

Answer 4

It suggests that aggression as a characteristic is highly heritable

Question 5

Who conducted a depletion study?

Answer 5

Kim et al 1997

Question 6

What did kim do?

Answer 6

Kim removed the MAOA gene from mice

Question 7

Kim found that the knockout mice with dramatically elevated levels of monoamines are hyper aggressive and demonstrate extreme fear responses

True or false

Answer 7

True

Question 8

What else did the Kim study show?

Answer 8

It showed that elevated levels of monoamines during the development and growth of the brain change structure and function

Question 9

What is the more common version of the MAOA called?

Answer 9

MAOA L

Question 10

Who studied the Dutch family ?

Answer 10

Brunner

Question 11

Aggression can be adaptive and serve a fitness advantage it’s likely to have what ?

Answer 11

A genetic component

Question 12

Why were historical aims to isolate the Y chromosome flawed?

Answer 12

Due to poor methodology

Question 13

Describe the relationship between aggression and genes

Answer 13

Highly complex with multiple genetic variants contributing and interacting with each other and the environment

Question 14

What does MAOA do?

Answer 14

It oxidises monoamines

Question 15

Who came up with landmark research linking a single rate genetic mutation to high levels of aggressive behaviour?

Answer 15

Brunner

Question 16

What did Kim’s mice demonstrate ?

Answer 16

They demonstrated extreme fear responses

Question 17

What did the depletion studies show?

Answer 17

It shows how elevated levels of monoamines during development and growth of the brain can change brain structure and function

Question 18

If a male has the MAOA L gene what will his behaviour be like?

Answer 18

He has the potential to be particularly aggressive however ONLY with an adverse childhood

Question 19

What did Caspi 2002 studies show?

Answer 19

The complexity of genes and the environment

MAOA L and childhood

Question 20

Genes can predispose not determine behaviour and can act differently in different environment

True or false

And who concluded this statement

Answer 20

Caspi

True

Question 21

What were Caspi’s strengths?

Answer 21

Large sample - 1000+
Even male female ratio 
Human sample 
Prospective design 
Reliability - replication by Kim-Cohen 2006

Question 22

Who replicated Caspi’s findings in a large scale meta analysis

Answer 22

Kim Cohen 2006

Question 23

Who extended the knowledge of mechanism of MAOA L gene?

Answer 23

Meyer-linenberg

Question 24

Under in necessary environmental conditions what can happen to brain structure and chemistry according to lindenberg

Answer 24

The limbic system and prefrontal cortex reduction. Hyperactivity of amygdala.

Question 25

According to Neural theories of aggression what causes aggression?

Answer 25

Low levels of serotonin

Low levels of cortisol