Localisation of Function (LoF)
The theory that specific parts of the brain are responsible for specific behaviours/mental processes
Hemispheres
• LoF splits the forebrain (cerebral cortex) into 2 hemispheres
• Left: verbal processes
• Right: non-verbal processes
Lobes
• Each has 4 lobes with specific functions:
• Frontal, parietal, occipital, temporal
Frontal Lobe
Executive functioning and motor control
Parietal Lobe
Integrating sensory information
Occipital Lobe
Visual processing
Temporal Lobe
Memory and auditory processing
Hippocampus
• Eg; hippocampus within spatial memory
• 'Seahorse shaped' structure that forms part of the limbic system and is situated in the medial temporal lobes
• Becomes active during tasks involving spatial navigation
fMRI
Functional magnetic resonance imaging
• Shows function as opposed to just structure
• When a brain region is active during the performance of a task, the organism supplies it with oxygenated blood
• Oxygenated blood emits pulses of energy when placed in an external magnetic field - response dedpends on flow and level of oxygen
• fMRI places the brain in an external magnetic field and detects the energy pulses emitted by the blood - allows us to see which brain areas are most active during the performance of a task
BOLD signal
Signal that is analysed by the fMRI scanner to reconstruct brain activity = BOLD (blood-oxygen-level-dependent) signal
Major Depressive Disorder (MDD)
is diagnosed when an individual experiences 2 weeks of depressed mood or a lost of interest and pleasure
MDD symptoms
• At least 4 symptoms must be present across a range of categories:
• Affective (guilt)
• Behavioral (passivity)
• Cognitive (suicidal thoughts)
• Somatic (loss of energy)
Gene
• Considered the basic unit of inheritance
• Contain the information needed to specify physical and biological traits
• Humans have 2 copies (alleles) of each gene, one inherited from each biological parent
• 2 copies can be the same (homozygous) or different (heterozygous)
• Sometimes a gene's DNA sequence changes (mutates)
• Allele combinations determine our genotype and our resulting traits are our phenotype
• Psychologists argue that some genes can give rise to physiology that gives rise to specific behaviours
5-HTT gene
• Eg; inheriting mutations of the 5-HTT (serotonin transporter) gene increases vulnerability to MDD
Serotonin
Neurotransmitter involved in controlling mood
Serotonin Hypothesis
Dysfunctional serotonergic neurons can affect sensitivity to stress and difficulties with emotional regulation
Diathesis Stress Model
Proposes that genetic vulnerability combined with environmental stressors can cause MDD
Genetic similarity
Biological psychologists propose that a trait has an underlying genetic component (is heritable) when the probability of 2 people sharing that trait increases with their proportion of shared genes
Twins
• Provide a unique way to investigate this as there are 2 types of twins with different levels of genetic similarity:
• Monozygotic (MZ) twins share ~100% of DNA
• Dizygotic (DZ) twins share ~50% of DNA
Concordance rates
• Twins studies measure the concordance rates of a particular trait across the 2 different types of twins
• Concordance rate: refers to the chance that one twin will have a particular trait, given that the other twin has it
• If MZ twins raised tgt have a significantly higher concordance rate for MDD than DZ twins raised together, it is assumed that the development is partly due to genetics/'nature'
• Higher concordance rates of 100 are rare for any trait, suggesting that the development of most traits is also partly due to the environment/'nurture'
Diffusion of Responsibility
• When there are other people present, we assume that someone else will help
• More people present = less likely one is to help
Informational Social Influence
• A form of conformity in which we figure out how to behave by watching the behaviour of others
• If others don't help, we won't either
Evaluation Apprehension
The fear of social criticism for helping in a situation where helping was unnecessary
Priming
It is suggested that if one is aware of these factors, they are able to be primed into showing more prosocial behaviors
Social Norms
• If social norms - actions considered typical within a group - determine helping behvaiour, it can be argued that changing norms may decrease bystanderism and increase prosocial behaviour
• Priming can be done through media such as video games promoting prosocial behaviour
Vulnerability Models
explain that MDD develops as a result of the interaction between...
Protective Factors
Factors which protect against the development of MDD in spite of vulnerability factors
Vulnerability Factors
Factors which, on their own, don't cause MDD, but increase the risk of developing MDD
Provoking Agents
• Factors which contribute to acute and ongoing stress
• Whether these trigger the onsent of MDD depends on the number of protective and vulnerability factors
Distributive Processing
Although some brain structures play very specialised roles, it is generally accepted that many cognitive functions involve multiple brain structures
Amygdala
• Eg; amygdala in the medial temporal lobe plays a role in regulating emotions
• Suggested that psychopaths - those who show less altruistic behaviours - have reduced amygdala responsiveness to fearful expressions and reduced amygdala volume
Twins
• Provide a unique way to investigate this as there are 2 types of twins with different levels of genetic similarity:
• Monozygotic (MZ) twins share ~100% of DNA
• Dizygotic (DZ) twins share ~50% of DNA
Concordance Rates
• Twins studies measure the concordance rates of a particular trait across the 2 different types of twins
• Concordance rate: refers to the chance that one twin will have a particular trait, given that the other twin has it
Nature vs Nurture
• If MZ twins raised tgt have a significantly higher concordance rate for MDD than DZ twins raised together, it is assumed that the development is partly due to genetics/'nature'
• Higher concordance rates of 100 are rare for any trait, suggesting that the development of most traits is also partly due to the environment/'nurture'
Cognitive Vulnerability Model for Depression
• Proposes that people who have certain cognitive characteristics are more likely to become depressed
• Makes an individual more vulnerable
Beck's Cognitive Theory
Composed of 3 components: Negative cognitive biases, Negative self-schemas, Negative triad
Negative Cognitive Biases
They are more likely to focus on negative aspects of a situation, being prone to illogical thinking patterns by distorting and misinterpreting information
Negative Self-Schemas
Interpreting information about themselves in a negative way which could lead to cognitive biases
Negative Triad
A negative and irrational view of ourselves, our future, and the world around us
6 Types of Faulty Thinking
• Arbitrary Inference: drawing conclusions based on little/no evidence
• Dichotomus Thinking: an all-or-nothing approach to viewing the world
• Magnification: overestimating the significance of negative events
• Overgeneralisation: applying the outcome of a single incident to all similar incidents
• Personalisation: sssuming that others' behaviour is done to hurt ot humiliate you
• Selective Abstraction: drawing conclusions by focusing on a single part of a whole
Negative Response Styles Theory (rumination)
Focused attention on the symptoms of distress and worrying about the meaning of it
Negative Responses
• Low confidence in decision-making
• Over-analysis and over-interpretation of events
• Vacillation between uncertainty and hopelessness
• Thoughts aligned with Beck's negative cognitive triad and negative self-schemas
Prevalence Rates
Are a statistical concept referring to the percentage of individuals within a population who are affected by a specific disorder at a given time
Period Prevalence
Proportion of people in a given population who have the disorder within a given time interval (Eg; 12 month prevalence/lifetime prevalence)
Point Prevalence
Where the proportion of people in a given population are currently diagnosed with the disorder
Problematic prevalence rates
• Prevalence rates can be problematic because a diagnosis is not always reliable across cultures
• Symptoms may be different for the same disorder in different cultures
Reasons prevalence rates differ
• There may be real differences in rate of depression - in some countries and demographics people are truly more likely to get depressed
• Eg; theory of vulnerability models suggests prevalence differs between genders due to different risk and protective factors for different groups
• There may be differences in how often depression is reported
• Eg; theory of explanatory models suggests prevalence differs between cultures due to differences in manifestations of symptoms between cultures/cultural attitudes towards depression
Informational Social Influence
• A form of conformity in which we figure out how to behave by watching the behaviour of others
• If others don't help, we won't either
Evaluation Apprehension
The fear of social criticism for helping in a situation where helping was unnecessary
Arousal Cost Reward Model
• We are motivated to help people not because of empathy, but as a way of reducing negative feelings
• "Arousal" = negative emotional state such as fear or sympathy
• When recognising this negative state, we then weigh the costs of helping vs not helping
• If the costs are higher than the rewards for helping, then we are unlikely to help someone in need of help
Thinking
The process of using knowledge and information to make plans, interpret the world, and make predictions about the world in general
Decision-making
The process of identifying and choosing alternatives based on the values and preferences of the decision-maker
Anchoring Bias
• When we base our decisions too heavily on an initial piece of information where the following judgements are based around that intial anchor
• Eg; if you first see a T-shirt that costs $1000, then see a second one that costs $100, you're prone to see the second shirt as cheap
Dual Process Model (DPM)
• Occurs due to heuristics within the DPM
• System 1: Quick and intuitive way of thinking therefore uses...
• Heuristics: mental shortcuts that are used to make quick decisions by focusing on specific aspects of information and disregarding others
Cognition
Mental process of acquiring and interpreting knowledge
Emotion
The mental state/feelings of humans
Emotion and Cognition
• Emotion and cognition are intertwined
• Emotions are believed to shape the experiences of events in regards to personal relevance - guiding individuals on how to react to certain situations
Flashbulb Memory (FBM)
• Highly detailed, vivid "snapshots" of a moment where extreme emotions were present
• Includes details such as time, place, who a person was with , what they were doing, how they felt, how others felt, and the consequences of the event
• Eg; graduating college may be a vivid, but detailed memory despite it not being purposefully rehearsed
Special Mechanism Hypothesis
There is a biological memory mechanism that creates a permanent record of an experience that exceeded critical levels of surprise
Importance Driven Model
Personal consequences determine intensity of emotional reactions
Reconstructive Memory
When memories are formed but not all of the details are remembered
Schemas
Mental representations that helps us process and interpret information from the world
Schema Processing
When a memory is reconstructed based on the individual's prior knowledge in what aligns with their schemas
Leading Questions
Questions that are suggestive in some way
Post-event Information
Any information that you are exposed to after you have witnessed something
Misinformation Effect
Post-event information facilitate schema processing - influences the accuracy of recall
Endocrine System
Consists of glands that produce and secrete hormones
Hormones
Class of chemicals that affect behaviour
• Are secreted into the bloodstream by glands that make up the endocrine system
• Can only produce reactions in certain cells known as target cells, that have an appropriate receptor site for the hormone
Stress
When the perceived demand of a situation is greater than the individual's perceived ability to cope
Stressor
• Any event that leads to the experience of being stressed
• Includes acute (short-term) and chronic (long-term) stress
Fight or Flight Response
• Endocrine and nervous system produced fight or flight response
• When you experience a stressor, the hypothalamus activates the sympathetic branch in the nervous system
Adrenaline
Is released from the adrenal medulla into the bloodstream and triggers a sympathetic state
• Binds to receptor sites on target cells in the amygdala, increasing its activity
• Causes arousal and fight or flight response
• Plays a role in cognition - enhancing consolidation of declarative memories associated with fear, particularly episodic memories
Beta-Blockers
Chemical substance that is capable of binding to adrenaline receptor sites thus preventing it from activating the amygdala
System 1
Intuitive thinking, fast and effortless in processing
System 2
Rational thinking, slow and effortful in processing
Heuristics
• Mental shortcuts that are used to make quick decisions by focusing on specific aspects of information and disregarding others (employed in system 1 thinking)
• Leads to the formation of biases
Anchoring bias
When we base our decisions too heavily on an initial piece of information, linking to system 1 thinking, where the following judgements are based around that initial anchor
Memory
The process where information is encoded, stored, and retrieved
Multi-Store Model (MSM)
Proposed by Atkinson and Shriffin - proposes that memory is made from 3 stores: sensory memory, short term memory (STM), and long term memory (LTM)
Capacity
How many pieces of information a store can hold
Duration
How long a piece of information can be stored for
Sensory memory
Capacity: unlimited
Duration: 0.3-4 seconds
Uses echoic (sound) and iconic (visual) encoding
STM
Capacity: 7+/-2 items
Duration: 15-30 seconds
LTM
Capacity: unlimited
Duration: lifetime
Uses semantic (meanings) encoding
Process
• Stimuli from environment goes through sensory memory
• If attention is paid, goes to STM
• Rehearsal keeps stimuli in STM - otherwise decay/displacement occurs and it is forgotten
• Elaborate rehearsal transfers stimuli to LTM
• Stimuli from LTM can be retrieved from LTM to STM - otherwise forgotten through interference or retrieval failure
Maintenance rehearsal
Used to memorise information through repetition (improves STM)
Chunking
Technique where information is divided into smaller chunks/sections and then are rehearsed so they can be maintained
Serial position effect
Describes how the position of an item on a list affects memory recall
Primacy effect
Items at the start of a list are recalled greater than in the middle
Recency effect
Items at the end of a list are recalled greater than in the middle
Working Memory Model (WMM)
Proposed by Baddley and Hitch - specific to structure of STM
• Central executive
• Phonological loop
• Visuospatial sketchpad
• Episodic buffer
Central Executive
• Controls all other systems and directs attention to particular tasks
• This information comes from the LTM or sensory store but has limited capacity
Phonological Loop
• Holds auditory information and has limited capacity
• Can be further divded into 2 parts:
• Phonological store: acts as 'inner ear' - holds sound
• Articulatory control system: acts as 'inner voice' - allows maintenance rehearsal
Visuospatial Sketchpad
• Acts as 'inner eye' - holds visual and spatial information and has limited capacity
• Can be further divided into 2 parts
• Visual cache: stores visual information about form and colour
• Inner scribe: deals with spatial relationships
Episodic Buffer
• Extra storage system that has limited capacity
• Explains how we can integrate and make use of information from different memory stores
Schemas
Mental representations that helps us process and interpret information from the world
Schema Theory
Certain ideas (schemas) are used to relate different pieces of information together to help us better understand things
Top-down processing
When pre-exisiting information is used to organise individual features into a unified whole
Bottom-up processing
Analysis of the smaller features to build up to a complete perception
Accommodation
New information can change an exisiting schema