Brain Neurochemistry Explanation

Smoking Addiction and the Brain Neurochemistry Explanation

Smoking can cause many harmful effects like emphysema or cancer, but people still smoke because of an addiction to a chemical in the cigarette called nicotine.

Cigarettes

For decades now, the harmful effects of smoking have been made known to the public.
- Cancer, bronchitis, and emphysema are all serious diseases caused by smoking.
But people still smoke. Addiction to cigarettes is due to a chemical called nicotine.

Nicotine

Nicotine alters brain neurochemistry.
It triggers the release of dopamine in the brain, which causes higher levels in the brain as well as increased dopamine stimulation on neurons.
Dopamine is a neurotransmitter that creates feelings of relaxation and pleasure.
Once a neurotransmitter has been sent across a synapse to stimulate the next neuron, they are removed from the synapse through a process called reuptake.

Neurotransmitter

Once the neurotransmitters are removed, the feelings associated with that particular neurotransmitter also disappear.
- For example, once dopamine reuptakes, the feelings of relaxation and pleasure diminish.
So for people to regain these feelings, they need more dopamine and consume more of the drug that caused it. In this case, cigarettes.

Dopamine

If people smoke regularly, then people’s bodies regularly expect the dopamine released caused by the nicotine.
The body will also start to reduce the amount of dopamine it releases naturally, so people rely on the nicotine as a source of dopamine.
People need to smoke regularly to maintain a normal level of dopamine.
Smoking behaviour is reinforced because of this biological need. Consequently, an addiction develops.

Withdrawal

It is very hard on the body to quit smoking as people need the levels of dopamine maintained.
When a person quits smoking, their body lacks dopamine, causing unpleasant withdrawal symptoms.
- These symptoms include irritability, anxiety, nausea, and sleep issues.

Olds and Milner (1954)

Olds and Milner (1954) studied the effects of brain neurochemistry in addiction; specifically the effects of dopamine in rats. It could potentially explain the importance of dopamine.

Condition 1

Method:
- Rats had an electrode directly connected to the hypothalamus, which when stimulated, releases dopamine.
- Rats could step on a lever that caused an impulse to be sent to the hypothalamus, thereby releasing dopamine.
Results:
- Rats were found to voluntarily (did not have to be forced) press the lever.

Condition 2

Method:
- Rats with the electrode in place in the hypothalamus had to walk across an area of a cage where a painful electric shock was given in order to press the lever.
Results 2:
- Even with the electric shock, rats chose to walk over to press the lever.

Conclusion

The rats voluntarily chose to press the lever, even if they had to endure a painful shock first, to receive a dosage of dopamine.
This shows the effect of dopamine as being a reward and the fact that it was addictive.

Weaknesses of study

There are several critiques to this study.
The first is that it was unethical. The rats were purposefully hurt to complete the study. Many argue that this is animal cruelty.
Secondly, the study was conducted on rats, not on humans, so the findings cannot necessarily be generalised to humans.

Strengths of study

A strength of the study was that it was a laboratory study, so highly controlled.
This increases the reliability of the results.

Evaluation of the Brain Neurochemistry Explanation of Addiction

The explanation states that addiction is caused by organisms wanting to maintain levels of dopamine (pleasure neurotransmitter) by consuming substances.

Strength - proven

There are three main strengths to this explanation:
Firstly, Olds and Milner (1954) and other researchers have provided evidence of this theory through scientific research.
- They have proven that dopamine plays a role in addiction.

Strength - cause and effect

Secondly, because the studies were done in a laboratory setting, this means that they can be highly controlled.
In these circumstances, extraneous variables are limited and causal relationships can be established.
- For example, maintain dopamine levels in the brain is a cause of addiction.

Strength - Zhang et al. (2012) support

Finally, another study conducted by Zhang et al. (2012) also supported the notion that nicotine plays a part in smoking addiction.
They found that those that had quit smoking had abnormal levels of dopamine after they had quit.
The study was conducted on mice who were given nicotine for several weeks.
They stopped giving them nicotine suddenly and found that dopamine productions were lower than normal.

Weakness - reductionist

There are three weaknesses to the brain neurochemistry explanation.
Firstly, the approach is reductionist.
The explanation tries to pare down addictive behaviour to differences in neurotransmitter levels.
The approach ignores other factors such as learning theory or other psychological factors.

Weakness - genetics

Secondly, the role that genetics plays is also ignored.
A study conducted by Doweiko (2002) examined adoption records.
They found that among 3,000 people, biological children of alcoholics were more likely to become alcoholics themselves.
Even if the children were raised by non-alcoholic adoptive parents, there was little to no effect.
This means there must be a genetic influence to addiction.

Weakness - generalisability

Finally, Zhang (2012) and Olds and Milner (1954) used animals in their studies.
Scientists cannot necessarily generalise these findings to humans.

1Social Influence

1.1Social Influence

1.1.1Conformity

1.1.2Asch (1951)

1.1.3Sherif (1935)

1.1.4Conformity to Social Roles

1.1.5BBC Prison Study

1.1.6End of Topic Test - Conformity

1.1.7Obedience

1.1.8Analysing Milgram's Experiment

1.1.9Agentic State & Legitimate Authority

1.1.10Variables of Obedience

1.1.11Resistance to Social Influence

1.1.12Minority Influence & Social Change

1.1.13Minority Influence & Social Impact Theory

1.1.14End of Topic Test - Social Influences

1.1.15Exam-Style Question - Conformity

1.1.16Top Grade AO2/AO3 - Social Influence

2Memory

3Attachment

3.1Attachment

3.1.1Caregiver-Infant Interaction

3.1.2Condon & Sander (1974)

3.1.3Schaffer & Emerson (1964)

3.1.4Multiple Attachments

3.1.5Studies on the Role of the Father

3.1.6Animal Studies of Attachment

3.1.7Explanations of Attachment

3.1.8Attachment Types - Strange Situation

3.1.9Cultural Differences in Attachment

3.1.10Disruption of Attachment

3.1.11Disruption of Attachment - Privation

3.1.12Overcoming the Effects of Disruption

3.1.13The Effects of Institutionalisation

3.1.14Early Attachment

3.1.15Critical Period of Attachment

3.1.16End of Topic Test - Attachment

3.1.17Exam-Style Question - Attachment

3.1.18Top Grade AO2/AO3 - Attachment

4(2026 Exams) Psychopathology

4.1Psychopathology

4.1.1Abnormality

4.1.2Abnormality 2

4.1.3Phobias, Depression & OCD

4.1.4Phobias: Behavioural Approach

4.1.5Evaluation of Behavioural Explanations of Phobias

4.1.6Depression: Cognitive Approach

4.1.7OCD: Biological Approach

4.1.8Evidence for the Biological Approach

4.1.9End of Topic Test - Psychopathy

4.1.10Exam-Style Question - Phobias

4.1.11Top Grade AO2/AO3 - Psychopathology

4.1.12Diagnostic Misconceptions - Phobia vs Fear

4.1.13Diagnostic Misconceptions - Depression & Self-Harm

4.1.14Diagnostic Misconceptions - Desensitisation

5Approaches in Psychology

5.1Approaches in Psychology

5.2Comparison of Approaches (A2 only)

5.2.1Psychodynamic Approach

5.2.2Cognitive Approach

5.2.3Biological Approach

5.2.4Behavioural Approach

5.2.5End of Topic Test - Comparison of Approaches

6Biopsychology

6.1Biopsychology

6.1.1Nervous System Divisions

6.1.2Neuron Structure & Function

6.1.3Neurotransmitters

6.1.4Endocrine System Function

6.1.5Fight or Flight Response

6.1.6The Brain (A2 only)

6.1.7Localisation of Brain Function (A2 only)

6.1.8Studying the Brain (A2 only)

6.1.9CIMT (A2 Only) & Postmortem Examinations

6.1.10Biological Rhythms (A2 only)

6.1.11Studies on Biological Rhythms (A2 Only)

6.1.12End of Topic Test - Biopsychology

6.1.13Top Grade AO2/AO3 - Biopsychology

6.1.14Diagnostic Misconceptions - Plasticity & Recovery

6.1.15Diagnostic Misconceptions - Endogenous Pacemakers

7(2027 Exams) Clinical Psychology & Mental Health

7.1Clinical Psychology & Mental Health

7.1.1Deviation from Social Norms

7.1.2Deviation from Social Norms 2

7.1.3Phobias, Depression & OCD

7.1.4Phobias: Behavioural Approach

7.1.5Evaluation of Behavioural Explanations of Phobias

7.1.6Depression: Cognitive Approach

7.1.7OCD: Biological Approach

7.1.8Evidence for the Biological Approach

7.1.9End of Topic Test - Psychopathy

7.1.10Exam-Style Question - Phobias

7.1.11Top Grade AO2/AO3 - Psychopathology

7.1.12Diagnostic Misconceptions - Phobia vs Fear

7.1.13Diagnostic Misconceptions - Depression & Self-Harm

7.1.14Diagnostic Misconceptions - Desensitisation

8Research Methods

8.1Research Methods

8.1.1Experimental Method

8.1.2Observational Techniques

8.1.3Covert, Overt & Controlled Observation

8.1.4Self-Report Techniques

8.1.5Correlations

8.1.6Exam-Style Question - Research Methods

8.1.7End of Topic Test - Research Methods

8.1.8Diagnostic Misconceptions - Sign Test

8.1.9Diagnostic Misconceptions - Content & Thematic

8.1.10Diagnostic Misconceptions - Valid vs Reliable

8.1.11Diagnostic Misconceptions - Confounding Variable

8.2Scientific Processes

8.2.1Aims, Hypotheses & Sampling

8.2.2Pilot Studies & Design

8.2.3Questionnaires

8.2.4Variables & Control

8.2.5Demand Characteristics & Investigator Effects

8.2.6Ethics

8.2.7Limitations of Ethical Guidelines

8.2.8Consent & Protection from Harm Studies

8.2.9Peer Review & The Economy

8.2.10Validity (A2 only)

8.2.11Reliability (A2 only)

8.2.12Features of Science (A2 only)

8.2.13Paradigms & Falsifiability (A2 only)

8.2.14Scientific Report (A2 only)

8.2.15Scientific Report 2 (A2 only)

8.2.16End of Topic Test - Scientific Processes

8.3Data Handling & Analysis

8.3.1Types of Data

8.3.2Descriptive Statistics

8.3.3Correlation

8.3.4Evaluation of Descriptive Statistics

8.3.5Presentation & Display of Data

8.3.6Levels of Measurement (A2 only)

8.3.7Content Analysis (A2 only)

8.3.8Case Studies (A2 only)

8.3.9Thematic Analysis (A2 only)

8.3.10End of Topic Test - Data Handling & Analysis

8.4Inferential Testing

8.4.1Introduction to Inferential Testing

8.4.2Sign Test

8.4.3Piaget Conservation Experiment

8.4.4Non-Parametric Tests

9Issues & Debates in Psychology (A2 only)

9.1Issues & Debates in Psychology (A2 only)

9.1.1Culture Bias

9.1.2Sub-Culture Bias

9.1.3Gender Bias

9.1.4Ethnocentrism

9.1.5Cross Cultural Research

9.1.6Free Will & Determinism

9.1.7Comparison of Free Will & Determinism

9.1.8Reductionism & Holism

9.1.9Reductionist & Holistic Approaches

9.1.10Nature-Nurture Debate

9.1.11Interactionist Approach

9.1.12Nature-Nurture Methods

9.1.13Nature-Nurture Approaches

9.1.14Idiographic & Nomothetic Approaches

9.1.15Socially Sensitive Research

9.1.16End of Topic Test - Issues and Debates

10Option 1: Relationships (A2 only)

10.1Relationships: Sexual Relationships (A2 only)

10.1.1Sexual Selection & Human Reproductive Behaviour

10.1.2Intersexual & Intrasexual Selection

10.1.3Evaluation of Sexual Selection Behaviour

10.1.4Factors Affecting Attraction: Self-Disclosure

10.1.5Evaluation of Self-Disclosure Theory

10.1.6Self Disclosure in Computer Communication

10.1.7Factors Affecting Attraction: Physical Attributes

10.1.8Matching Hypothesis Studies

10.1.9Factors Affecting Physical Attraction

10.1.10Factors Affecting Attraction: Filter Theory 1

10.1.11Factors Affecting Attraction: Filter Theory 2

10.1.12Evaluation of Filter Theory

10.1.13End of Topic Test - Sexual Relationships

10.2Relationships: Romantic Relationships (A2 only)

10.2.1Social Exchange Theory

10.2.2Evaluation of Social Exchange Theory

10.2.3Equity Theory

10.2.4Evaluation of Equity Theory

10.2.5Rusbult’s Investment Model

10.2.6Evaluation of Rusbult's Investment Model

10.2.7Relationship Breakdown

10.2.8Studies on Relationship Breakdown

10.2.9Evaluation of Relationship Breakdown

10.2.10End of Topic Test - Romantic relationships

10.3Relationships: Virtual & Parasocial (A2 only)

10.3.1Virtual Relationships in Social Media

10.3.2Evaluation of Reduced Cues & Hyperpersonal

10.3.3Parasocial Relationships

10.3.4Attachment Theory & Parasocial Relationships

10.3.5Evaluation of Parasocial Relationship Theories

10.3.6End of Topic Test - Virtual & Parasocial Realtions

11Option 1: Gender (A2 only)

11.1Gender (A2 only)

11.1.1Sex, Gender & Androgyny

11.1.2Gender Identity Disorder

11.1.3Biological & Social Explanations of GID

11.1.4Biological Influences on Gender

11.1.5Effects of Hormones on Gender

11.1.6End of Topic Test - Gender 1

11.1.7Kohlberg’s Theory of Gender Constancy

11.1.8Evaluation of Kohlberg's Theory

11.1.9Gender Schema Theory

11.1.10Psychodynamic Approach to Gender Development 1

11.1.11Psychodynamic Approach to Gender Development 2

11.1.12Social Approach to Gender Development

11.1.13Criticisms of Social Theory

11.1.14End of Topic Test - Gender 2

11.1.15Media Influence on Gender Development

11.1.16Cross Cultural Research

11.1.17Childcare & Gender Roles

11.1.18End of Topic Test - Gender 3

12Option 1: Cognition & Development (A2 only)

12.1Cognition & Development (A2 only)

12.1.1Piaget’s Theory of Cognitive Development 1

12.1.2Piaget's Theory of Cognitive Development 2

12.1.3Schema Accommodation Assimilation & Equilibration

12.1.4Piaget & Inhelder’s Three Mountains Task (1956)

12.1.5Conservation & Class Inclusion

12.1.6Evaluation of Piaget

12.1.7End of Topic Test - Cognition & Development 1

12.1.8Vygotsky

12.1.9Evaluation of Vygotsky

12.1.10Baillargeon

12.1.11Baillargeon's studies

12.1.12Evaluation of Baillargeon

12.1.13End of Topic Test - Cognition & Development 2

12.1.14Sense of Self & Theory of Mind

12.1.15Baron-Cohen Studies

12.1.16Selman’s Five Levels of Perspective Taking

12.1.17Biological Basis of Social Cognition

12.1.18Evaluation of Biological Basis of Social Cognition

12.1.19Important Issues in Social Neuroscience

12.1.20End of Topic Test - Cognition & Development 3

12.1.21Top Grade AO2/AO3 - Cognition & Development

13Option 2: Schizophrenia (A2 only)

13.1Schizophrenia: Diagnosis (A2 only)

13.1.1Classification & Diagnosis

13.1.2Reliability & Validity of Diagnosis

13.1.3Gender & Cultural Bias

13.1.4Pinto (2017) & Copeland (1971)

13.1.5End of Topic Test - Scizophrenia Diagnosis

13.2Schizophrenia: Treatment (A2 only)

13.2.1Family-Based Psychological Explanations

13.2.2Evaluation of Family-Based Explanations

13.2.3Cognitive Explanations

13.2.4Drug Therapies

13.2.5Evaluation of Drug Therapies

13.2.6Biological Explanations for Schizophrenia

13.2.7Dopamine Hypothesis

13.2.8End of Topic Test - Schizoprenia Treatment 1

13.2.9Psychological Therapies 1

13.2.10Psychological Therapies 2

13.2.11Evaluation of Psychological Therapies

13.2.12Interactionist Approach - Diathesis-Stress Model

13.2.13Interactionist Approach - Triggers & Treatment

13.2.14Evaluation of the Interactionist Approach

13.2.15End of Topic Test - Scizophrenia Treatments 2

13.2.16Diagnostic Misconceptions - CBT & CBTp

14Option 2: Eating Behaviour (A2 only)

14.1Eating Behaviour (A2 only)

14.1.1Explanations for Food Preferences

14.1.2Birch et al (1987) & Lowe et al (2004)

14.1.3Control of Eating Behaviours

14.1.4Control of Eating Behaviour: Leptin

14.1.5Biological Explanations for Anorexia Nervosa

14.1.6Psychological Explanations: Family Systems Theory

14.1.7Psychological Explanations: Social Learning Theory

14.1.8Psychological Explanations: Cognitive Theory

14.1.9Biological Explanations for Obesity

14.1.10Biological Explanations: Studies

14.1.11Psychological Explanations for Obesity

14.1.12Psychological Explanations: Studies

14.1.13End of Topic Test - Eating Behaviour

15Option 2: Stress (A2 only)

15.1Stress (A2 only)

15.1.1Physiology of Stress

15.1.2Role of Stress in Illness

15.1.3Role of Stress in Illness: Studies

15.1.4Social Readjustment Rating Scales

15.1.5Hassles & Uplifts Scales

15.1.6Stress, Workload & Control

15.1.7Stress Level Studies

15.1.8End of Topic Test - Stress 1

15.1.9Physiological Measures of Stress

15.1.10Individual Differences

15.1.11Stress & Gender

15.1.12Drug Therapy & Biofeedback for Stress

15.1.13Stress Inoculation Therapy

15.1.14Social Support & Stress

15.1.15End of Topic Test - Stress 2

16Option 3: Aggression (A2 only)

16.1Aggression: Physiological (A2 only)

16.1.1Neural Mechanisms

16.1.2Serotonin

16.1.3Hormonal Mechanisms

16.1.4Genetic Factors

16.1.5Genetic Factors 2

16.1.6End of Topic Test - Aggression: Physiological 1

16.1.7Ethological Explanation

16.1.8Innate Releasing Mechanisms & Fixed Action Pattern

16.1.9Evolutionary Explanations

16.1.10Buss et al (1992) - Sex Differences in Jealousy

16.1.11Evaluation of Evolutionary Explanations

16.1.12End of Topic Test - Aggression: Physiological 2

16.2Aggression: Social Psychological (A2 only)

16.2.1Social Psychological Explanation

16.2.2Buss (1963) - Frustration/Aggression

16.2.3Social Psychological Explanation 2

16.2.4Social Learning Theory (SLT) 1

16.2.5Social Learning Theory (SLT) 2

16.2.6Limitations of Social Learning Theory (SLT)

16.2.7Deindividuation

16.2.8Deindividuation 2

16.2.9Deindividuation - Diener et al (1976)

16.2.10End of Topic Test - Aggression: Social Psychology

16.2.11Institutional Aggression: Prisons

16.2.12Evaluation of Dispositional & Situational

16.2.13Influence of Computer Games

16.2.14Influence of Television

16.2.15Evaluation of Studies on Media

16.2.16Desensitisation & Disinhibition

16.2.17Cognitive Priming

16.2.18End of Topic Test - Aggression: Social Psychology

17Option 3: Forensic Psychology (A2 only)

18Option 3: Addiction (A2 only)

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