The biological approach & Psychosurgery

What are the key terms of behaviour can be explained by neurons and neurotransmitters?

Nervous system composted of neurons, gaps called synapse, neurotransmitters chemicals that pass messages, Dopamine controls bodily movement and imbalance relates to schizophrenia, serotonin impacts the body emotions and motor skills

Cacioppo (2012)

Roots of mate attraction measured by scanning male participants in FMRI whilst viewing unattractive and attractive women, Brain released more dopamine with attractive women and none for unattractive

Aron et al (2008)

Dopamine plays a significant role in arousal and therefore the formation of romantic relationships as it activates reward centres of the brain and amplifies the effect of sex hormones.

Key terms of behaviour can be explained by brain structures and localisation

Cerebral cortex, two hemispheres, Frontal lobe (problem solving and motor skills), Parietal lobe (Sensory like pain , touch and temperature), Occipital lobe (visual information and stimuli), Temporal lobe (auditory information), Orbito cortex involved in response inhibition and mate selection.

Ishai (2007)

Observing beauty in members of the opposite sex raised action of the OFC in males and females, brain localisation does play a role in romantic relationships.

Key terms of Behaviour can be explained through the role of evolutionary influences

Natural selection (Charles Darwin), Survival of the fittest, fertility and reproductive value, mind is shaped to survive and reproduce.

David Buss (1989)

Cross cultural study whether males and females differ in partner choice, mate preference is based on survival to pass on genes. Fertility and reproductive value impacts mate choice, females value industriousness whereas males value reproductivity.

Biological explanation relationship formation

Evolutionary theory, desire to reproduce, women invest more in reproduction so are fussier in mate choice and select base on ability to contribute, males do not invest much as they only impregnate female and do not need to do anything else.

Trivers (1972)

Parental Investment Theory one factor that affects mate selection is parental investment and sex that invests more in offspring will have more preference, choice is driven by evolution females invest more time and energy than men.

Symons

Males look for females who have high reproductive value, a 13 year old girl has a high reproductive value and can produce offspring for around 40 years

Williams

Males do look for females with high fertility but also those who can look after offspring, 13 year old wouldn’t be suitable a more suitable candidate would be a woman aged 23 with high fertility and the ability to care for offspring.

Aim of psychosurgery

To relieve stress, anxiety and depression in patients that have not responded to other treatment, works by destroying parts of the brain by severing connection between areas of the brain.

Egas Moniz (1930)

invented the modern lobotomy called “prefrontal leucotomy“ drilling holes in the skull in order to access the brain and severe nerves with a leucotome.

Dr. Walter Freeman

Amended moniz technique and developed the trans obrital lobotomy, was a blind operation so they weren’t sure if nerves had been severed or not, nerves were severed by placing an icepick through the eye socket and hit with a hammer

Stereotactic psychosurgery

imaging like MRI scans locate precise points in the brain and sever connections, E.g OCD circuit linking teh OFC to structures like thalamus can be severed.

Deep Brain stimulation

alternative to psychosurgery, drill a hole about 14 mm into skull, surgeons insert thin electrode into thalamus and stimulate with electrical signals.

Wilkinson et al (2000)

improvements in 72% patients treatment for chronic pain, however patients left vegetablisized or numb, brain seizures

Pippard (1995)

Reported improvements in 62% of leuctomised depressed patients and 50% with mood disorders

Comer (2002)

Found a 6% fatality rate and severe physical side effects like brain seizures

Cosgrove and Rauch (2001)

Found Cingulotomy was 56% effective of OCD patients and 67% in capsulotomy, 25 patients currently treated annually in the US

Bilateral Cingulotomy

advantages over lobotomies and leucotomies as it is very accurate and doesn’t cut into skull, however it is still a last resort for patients

Bridges et al (1994)

Psychosurgery has no controlled trial against it so difficult to measure effectiveness, psychosurgery is limited in its uses e.g rarely used for phobias, schizophrenia

Szasz (1978)

Criticised psychosurgery as a persons psychological self is not physical and therefore if is illogical to suggest it can be operated on.

Mayberg (2005)

4 out of 6 patients who underwent DBS experienced significant improvements when small area of frontal lobe was stimulated, DBS is the most evolving psychosurgery as it can give precise information about these things.

What is a real life application?

Howard dully- lobotomy at 12 years old by walter freeman to control his behaviour, he didnt consent and has side effects like brain fog and a hole in his frontal lobe, felt 20 years behind and recovered because his brain was still developing.