Biological psychology

Techniques in cognitive neuroscience

The brain and mental illness

functional Magnetic Resonance Imaging (fMRI)

Diffusion Tensor Imaging (DMT)

Issues with neuroimaging

Reverse inference (Poldrack, 2006)

Esp. where specificity is unknown or weak

afforded "golden status" unjustifiably

Electroencephalography (EEG)

Techniques for treatment

Deep Brain Stimulation (DBS)

Parkinson's

brain surgery

treatment resistant OCD

depression

poorly understood despite neuroimaging

changes in cortical thickness

Atrophy in prefrontal cortex, amygdala and hippocampus (Pinel et al, 2022)

OCD

Fouche et al (2022) found no difference in subcortical structures for OCD patients

only when comorbid w anxiety and when taking meds

Bipolar Depressive Disorder

Type 1 and 2

lithium can be effective

reasons unclear but may be HPA axis dysregulation

disruptions in circ. rhythm and GABA; glutamate and dopamine transmission

Maletic & Raison (2014) found lower BDNF when depressed or manic

reward hypersensitivity suggests reward system issues which links with increased activity in prefrontal cortex and striatal reward circuits

neurally, appears that there is reduced gray matter

Socioeconomic Factors and neuro

Storrs et al., (2917) has found that malnutrition associated with poverty is sufficient to impact neurodevelopment

Neuroplasticity

700 new neurons per day in hippocampus in adults (Kempermann, 2013)

Kempermann and Gage (1999) studied rodents in enriched environemnts. Enriched environments -> neurogenesis in hippocampus as partly mediated by exercise.

Ma et al, (2017) suggest enriching environments may reduce or delay memory problems

hippocampus

well studied due to plasticity due to glucocorticoid receptor density

antipsychotics

believed to bind to dopamine receptors

effective against positive symptoms of psychotic disorders (hallucinations etc) as these are associated with overacitivity of dopamine in the mesolimbic area

not effective against negative symptoms (social withdrawal, numbing) as these are associated with UNDERactvitiy of dopamine in mesocortical areas.

Environmental psychology

Cohen et al., (1980) children in school under airport = higher blood pressure gave up easier

Brain damage studies

Phineas Gage (1848) frontal lobe and connetions between frontal lobe and subcortical structures affected

Wernicke's area (1874) damafge upper left temporal lobe

Broca's area (1861) damage left frontal lobe

Roger Sperry's split brain patients 1913-1994

electrical activity in the brain different levels of consciousness - also learning and perception and remembering

characterises microstructural changes measur

it is a diffusion weighted form of MRI that looks at diffusion of water to measure alterations in microstructure. Sensitive enough to see changes at cellular and microstructural level

Transcranial Direct Current Stimulation (tDCS)

uses electrodes, not as effective as ECT but may be used for those unfit for ECT

ECT

Transcranial Magnetic Stimulation (TMS)

powerful magnet over scalp to change neruonal activity in the brain

in depression, over right and left eyebrow

Janicakl (2002) TMS as effective as ECT

Luber et al., (2017) low effectiveness fix

FDA approved a "5 cm from x" approach

actually, fMRI better to localise individual target areas

Sack et al., (2005) found increased effectiveness when using fMRI

Luber et al., (2013) found using working memory tasks during several sessions of rTMS improved working memory performance

Computerised Axial Tomography (CT scan)

mild seizure by electric shock

extreme treatment resistant depression

Perrin et al (2012) found with fMRI that ECT had altered the connectivity in the forntal systems by downregulating the activity in the dorsal lateral prefrontal cortex, found to be part of the circuitry implicated in people with depression

Vagus Nerve stimulation

new trreatment that stimulates VN resulting in changing blood flow to brain. Marangell et al (2007) says similar effect as antidepressants

Phototherapy

for SAD

lots of X rays of brain from different angles to show density of different tissues in brain. Good for tumour checking etc

MRI

powerful magnet causes charge molecules to realign produce measurble field distoritions. Better view of soft tissue than CT

active brain areas need more energy when activited in the form of blood flow. fMRI measures changes in blood flow when patient is in action

Positron Emission Tomography (PET)

uses radioactive markers to measure brain blood flow. higher amounts of radioactivity in parts of brain that are active and needing more blood flow.

still needs to be validated with self report measures a lot of the time

Biopsychology of stress and health

The brain

hippocampus

involved in new memory formation and integration of memories into cerebral cortex

amygdala

situatated at each horn of the hippocampus. When in an emotionally arousing situation, the amygdala triggers the hippocampus to remember as many details as possible (Kensinger and Schacter, 2005)

Case of S.M with amygdala removed for epilepsy (Feinstein et al., 2012)

damage to other amuygdalae so bilateral damage in effect

not scared of anything except suffocation

consists of several nuclei. Lateral nucleus

receives info from all sensory systems (Pinel et al., 2022)

involved when there is emotional component (Pinel et al., 2022)

evaluates emotional significance of situations (Pinel et al., 2022)

Affect reward system (controversial) oiversue in kids in the USA (Van Der Kolk, 2014)

may affect pleasure seeking and relationships

no robust evidence for impact on development in children

loneliness

Holt-Lunstad et al., 2010) loneliness sme impact on health as obesitiy and inactivity

Anders Hansen (2021) like smoking a pack per day. Evolutationary explanation

mechanism:

shown to effect rates of herpes viral infetion and immune response to influenza vaccine (Pressman et al., 2005)

how lonely you FEEL (Hansen, 2021)

dysregulation of immune system by stress leading to inflammation (Jaremka et al., 2013)

white blood cells in lonely adults show different levels of gene expression compared to connected adults, making them more vulnerable to disease as their immune systems are less effective

prefrontal cortex

Stress

Fight or flight by Cannon (1929)

interpretation

primary: is it a threat

secondary: can I deal with it

in control associated with less intense fear response

hypothalamus (brain activation in response to threat)

stimulates pituitary gland to release adrenocorticotropic hormone (ACTH)

ACTH travels through bloodstream and stimulates adrenal glands at the top of kidneys. This HPA activation triggers release of adrenaline and noradrenaline from adrenal glands. Also cortisol from adrenal glands

increases sympathetic nervous activation: blood pressure, respiration rate, heart rate. Decreases parasympathetic nervous system.

more oxygenated blood to muscles.

cortisol increases blood glucose in the blood

more glucose to muscles for energy

stress and immunity

Cohen et al., (1998) cold viruses up the nose. The students with chronisc stress more infected

high levels of pronlonged stress can lead to HPA axis damage (Schacter et al., 2020)

chronic stress linked to depression with overactivation of HPA axis

hippocampus regulating stress response

hippocampus high density glucocorticoid receptors

monitors levels of cortisol and glucose in the blood. When critical signal to Hypothalamus to switch off HPA axis activiation

overuseof HPA over time lead to over- or underreacting to stress (Schacter et al., 2020)

Socioeconomic status and stress

study on civil servants showed low rank = higher mortality (Marmot et al., 1991)

stress of low SES impacts immunioty. Cohen et al., (1999) found those who perceive themselves as SES have higher rates of respiratory infection,

metacogntiion

believed to act on the lateral nucleus of amygdalae to suppress conditioned fear response (Pinel et al., 2022)

interacts with lateral nucleus of amygdalae complex by mediating learning about the context of fear related events

Turkheimer et al., (2013)

compared heritibility of intelligence in high, middle and low SES. Found only 10% heritability of SES in low income families. The gene may be there but expression no due to impoverished environment and other factors.

Turkheimer looked at 7 year olds but findings have been extended to babies and adolescents.

Stress from SES on immunity

self identified low SES = more respiratory illness (Cohen et al., 1999)

Childhood neglect -> reduced corpus callosum (Teicher et al., 2004)

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Stamoulis et al., (2015) early psychosocial neglect appears to impact neuronal maturation

Attachment

Dynamic Maturational Model of attachment (Crittenden, 2006)