BIOLOGICAL APPROACH: RAINE ET AL (1997) Flashcards
(68 cards)
1
Q
METHODOLOGY
A
2
Q
describe the experimental design.
A
The methodology involved a
* quasi-experiment
* with a matched-pairs design,
3
Q
IV and DV, BE SPECIFIC
identify the variables.
A
- whereby the independent variable (IV) is not guilty through reason of insanity (NGRI) or not,
- and the dependent variable (DV) is brain differences.
4
Q
identify the apparatus used by the researchers.
A
Raine used PET scans to investigate brain differences in non-murderers and murderers.
5
Q
how were these participants seperated into groups?
A
The participants consisted of two groups:
1. the experimental group of murderers
2. and the control group of non-murderers.
6
Q
state the characteristics of the experiental group: size, sex, mean age.
A
Within the experimental group, there were
* 41 murderers,
* 39 of whom were men,
* 2 were women,
* with a mean age of 34.3 years.
7
Q
describe the commonality within the experimental group.
A
All participants here had been
* charged with murder or manslaughter
* and pleaded
- NGRI
- or incompetence to stand trial.
8
Q
raine is an academic, so worked in a…
raine had access to them because they were reffered to where? and what purpose?
A
The participants were referred to the University of California
1. for examination
2.in order to obtain proof of their diminished capacity,
3. being that the murderers had some form of mental impairment.
9
Q
there were 41 patients in all. list each of the mental impairments and numbers within them respectively.
A
- Six had schizophrenia, as diagnosed by psychiatrists,
- **twenty-three **with a history of head injury or organic brain damage,
- three had a history of psychoactive drug abuse,
- two with an affective disorder,
- two with epilepsy,
- two had a history of hyperactivity and learning disability,
- and two with personality disorder.
6,23, 3, 2,2,2
10
Q
how were these participants prepared for the brain scan?
A
- All participants were instructed to be medication free
- and this was checked with a urine scan, two weeks prior to brain scanning.
11
Q
think match pairs!
how was the control group formed?
A
In addition, the control group was formed by matching each murderer with a normal individual of the same sex and age.
The six schizophrenics were matched with six schizophrenics from a mental hospital.
12
Q
mean age of control group?
A
These had a mean age of 31.7 years.
13
Q
describe the presence of mental impairments, if any, in the control group.
A
- The controls had no history of psychiatric illness,
- concordant with that of their close relatives, and
- no significant physical illness evident in screening examination.
-
None of the controls were taking medication.
*
14
Q
PROCEDURES
A
15
Q
describe the sample technique used.
A
Furthermore, the sample was obtained using opportunity sampling.
16
Q
describe the first step of the procedure.
A
- A PET scan was used to study the active brain
- and all participants were given an injection of fluorodeoxyglucose (FDG),
- a tracer which is taken up by active areas of the brain.
17
Q
why was this done, what did it allow?
A
Thus allowing comparisons between experimental and control groups to be drawn.
18
Q
describe the second step of the procedure.
A
- All participants were asked to do a **continuous performance task **(CPT)
- which specifically aimed to activate target areas of the brain,
- thus allowing **investigators to see how different areas **of the brain functioned.
19
Q
these were then combined into a three stage process to obtain a PET scan. what came first?
A
Participants were given a chance to practise the CPT before receiving the FDG injection.
20
Q
these were then combined into a three stage process to obtain a PET scan. what came second?
A
- 30 seconds before the FDG injection,
- participants started the CPT task to **avoid FDG labeling of the initial task **novelty.
21
Q
these were then combined into a three stage process to obtain a PET scan. what came third?
A
- 32 minutes following FDG injection, a PET scan was done of each participant.
- **10 horizontal slices **of their brain were recorded, using cortical peel and box techniques.
22
Q
how were these techniques recorded and why?
A
- The article** provided precise details of scanning techniques**
- so that the study could be replicated.
23
Q
FINDINGS
A
24
Q
raine et al’s findings pertain to three metrics of activity. what are these?
A
- reduced activity
- increased activity
- no difference in activity
25
what did raine et al find regarding reduced activity that links to previous literature?
* The study found **reduced activity** in the brains of murderers pleading not guilty through reason of insanity (**NGRI**) **relative to the control group **
* in **areas previously linked to violence.**
26
where was this reduced activity found?
This was found in the:
* prefrontal cortex,
* left angular gyrus,
* corpus callosum,
* amygdala,
* thalamus
* and **hippocampus** regions of the **left hemisphere**.
27
what did raine et al find regarding increased activity that links to previous literature?
* Additionally, the study found **increased activity in the brain of NGRI** participants **not previously linked** to violence,
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where was this increased activity found?
such as the
* cerebellum,
* amygdala,
* thalamus
* and **hippocampus** in the** right hemisphere**.
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what did raine et al find regarding no difference in activity that links to previous literature?
Furthermore, the study found** no difference** between NGRI and control groups **in areas previously not linked to violence** -
30
where was this no difference in activity found?
* the caudate,
* putamen,
* globus pallidus
* and midbrain.
31
how did findings show concurrent validity with areas identified in hypothesis?
* Moreover, **murderers displayed reduced glucose metabolism** in areas
* identified in the hypothesis **concurrently associated with violence,**
32
what were these areas identifed in the hypothesis associated with violence?
* abnormal asymmetries - reduced in activity on the left hemisphere, increased in the right hemisphere,
* amygdala,
* thalamus
* and hippocampus
*
33
what was found regarding difference in strcuture relative to the mental illness (e.g schizoid, mood affective, hyperactivity) form of mental impairment.
* and **no differences in many brain structures** notably that which were **associated with mental illness**,
* relative to the **control group**.
34
describe the findings relating to CPT Performance.
* Both groups performed similarly on the continuous performance task (CPT),
* thus observed brain differences were not related to task performance.
35
were any differences found between groups?
However, there were some uncontrolled differences between groups.
36
one of the diffrences was handedness. describe this.
For instance,
six of the murderers were left-handed,
37
what identified differences was there between the left and right handed?
though they had
1. **less amygdala asymmetry** +
2. **higher medial prefrontal cortex**
than right-handed murderers.
38
another difference was ethnicity. describe and discuss the effect, if any, it had on findings.
* Additionally, ethnic background,
**fourteen **of the murderers were **non-white**,
* but comparison showed **no significant racial difference** in brain activity *relative to white murderers*.
39
another difference was head injuries. describe and discuss the effect, if any, it had on findings.
* Regarding head injuries,
* **twenty-three** of the murderers had a **history of head injury**,
* however there was **no difference in murderers** between murderers without a history of brain injury.
40
CONCLUSIONS
41
what did concurrent findings establish?
* In conclusion, **past research** within *human* and *animal studies*
* has **identified links between areas of the brain and aggression**.
42
give an example of an area of the brain associated with violence.
For instance,
* the **amygdala is associated with aggressive behaviour** in *animals* and *humans*,
* whereby the **destruction of which** results in **fearlessness**,
* in turn **associated with violent activity**.
43
what did the findings of raine et al contribute to existing literature?
| like did their findings support this?
* Raine et.al’s **findings have concurrent validity** relative to these findings,
* which **provide preliminary evidence** that **murderers pleading NGRI have different brain functioning to normal **individuals.
44
raine et als conclusion can be broken down into 7 key points. what are these?
1. Not a single brain mechanism
2. Predisposition not cause
3. Potential confounding variables
4. Interactionist explanation
5. Not deterministic
6. PET Cannot diagnose violence
7. Cannot be generalised
45
describe the first conclusion that not a single brain mechanism causes violence.
That said, violent behaviour can best be explained by
* the disruption of a **network of interacting** brain mechanisms,
* **rather than any single structure**.
46
describe the second conclusion of predisposition not cause.
* Such disruption would **not cause violent behaviour**,
* but would **predispose** an individual to violent behaviour.
47
describe the third conclusion of potential confounding variables.
* Furthermore, whilst the study was **carefully designed**, consisting of a **large sample matched controls**,
* the investigators acknowledge that **head injury **and **IQ cannot be eliminated as confounding variables**.
48
describe the fourth conclusion of an interactionist explanation
of predisption to violence.
* Additionally, researchers emphasised that it *is important to recognise *that these **results do not demonstrate that violent behaviour is determined by biology alone**.
* There are **social**, **psychological**, **cultural** and **situational factors** that play an *important role in predisposition to violence*.
49
describe the fifth conclusion of free will
in committing crime.
The results ***do not*** demonstrate that murderers pleading NGRI are **not responsible** for their actions,
50
describe the sixth conclusion of PET is not a diagnostic tool +direction of association .
* **nor** that PET can be used as a **diagnostic tool for violent individuals**.
* The results **do not show that brain dysfunction causes violence**; it may even be **an effect of it**.
51
describe the seventh conclusion of findings not being generalised to violent behaviour.
**Nor** do the results show that these results, related to criminal behaviour, **can be generalised to violence** wholly.
52
All in all, what can be concluded from the findings?
Nevertheless, the findings evidence
* **an association between brain dysfunction and a predisposition towards violence**
* amongst **this specific group of NGRI** murderers .
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EVALUATION
54
METHODOLOGY
55
identify and describe the experimental design.
Foremost, in evaluating the *methodology* of the study,
* this study is an **experiment**,
* as there is an **independent variable,** not guilty through reason of insanity **(NGRI) or not**,
* and a **dependent variable**, **activity of brain regions**, *operationalised as fluorodeoxyglucose metabolism *.
56
more specifically though, what did NGRI mean for the design?
* However the **independent variable, criminal status **of the participant,
* was an **existing condition**, *not manipulated by the researcher *– a **quasi-experimental design**.
57
how does this effect the conclusions drawn?
* Therefore **causal conclusions**,
* like that **violent behaviour is determined **by biology alone,
* are **not justified**, as *acknowledged by Raine et al*.
58
why is this quasi-experiment methodology limited?
* Yet, there is the** risk that readers misinterpret **the findings,
* and **adopt a hard biological determinist perspective** to criminal behaviour
* - concerning given that **crime is often sensationalised in the media**.
59
on the other hand, the quasi-experimental design was advantageous because...
Conversely, this is advantageous in that it allowed Raine et al. to
1. investigate this **pertinent social issue **
2. that can **improve the understanding**, and thereby **rehabilitation of violent offenders**,
3. as well as **advance Lombroso’s (1976) biological theories of criminality **with greater validity via brain scans.
60
PROCEDURE
61
describe + identify the procedure.
* Secondly, in evaluating the procedure of the study,
* the **data was collected using PET scans**.
62
why is this advantageous?
* This offers a **novel, greater internally valid** method of *studying brain activity*.
* *Prior to this*, **researchers relied on post-mortem examinations **where **physiology could no longer be linked to behaviour**.
63
why does it have greater internal validity?
* PET scans are advantageous,
* as it permits Raine et al. to **examine detailed regions of the brain** and their **corresponding activity**, in **real-time**.
* Moreover, this** enabled associations to be drawn**,*presupposed* by the *knowledge of localisation of brain function*.
64
what does greater internal validity allow?
* Consequently, Raine et al. could **account for individual differences in neurocognitive processing**.
* This **increases generalisability** to an *external NGRI population*.
65
whats
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ALTERNATIVE EVIDENCE
67
identify and describe alternative evidence, including its findings.
* Furthermore, alternative evidence, namely **Yang & Raine (2009**)
* in a** meta-analysis of 43 imaging studies** examined both **antisocial** and **violent** behaviour,
* *concluding* that there is **significantly reduced prefrontal activity**
in *antisocial and/or violent individuals*.
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