Lesson 7 – Lateralisation of Function Flashcards
What is Lateralisation of Function?
Lateralisation of function- idea that 2 hemispheres of 🧠 have different specialisations
- right hemisphere of 🧠 responsible for left side of body and left hemisphere responsible for right side of body (hemispheric laterisation)
What is the corpus callosum?
Corpus callosum- nerve fibres which connects the 2 hemispheres
What is the left hemisphere mainly responsible for?
Left hemisphere dominant for language (Broca and Wernicke Areas)
What is the right hemisphere mainly responsible for?
Right hemisphere dominant for recognising faces
What are the evaluation points of Lateralisation of Function?
👍- increases ⬆️ neural processing capacity- using 1 hemisphere to engage in particular task leaves other hemisphere free to engage in another function
Rogers et al. (2004)- found lateralisation in 🐓 associated with ability to perform 2 tasks simultaneously (finding food and being vigilant for predators)
👎- individual differences- JW developed capacity to speak using right hemisphere- could speak about info presented to left or right hemisphere
Who are split-brain patients?
Patients who have their corpus callosum cut in order to prevent the violent ⚡️ activity caused by epileptic seizures (neurons 🔥) crossing from 1 hemisphere to the other
Who investigated split brain patients and when did they do so?
Sperry and Gazzaniga (1968)
What did Sperry and Gazzaniga (1968) do?
1) Patients asked to stare at dot in centre of screen and then info presented in either left or right visual field.
2) Then asked to make responses with either left 🖐(right hemisphere), right 🤚 (left hemisphere) or verbally 👄(left hemisphere) without being able to 👀 what their 🖐🤚 doing
3) If flashed image of 🐕 in right visual field and asked what they saw- able to answer ‘dog’ because info gone into left hemisphere where language centres are
4) BUT if 🐈 shown in left visual field and asked what they saw- ✖️ able to say because info gone to right hemisphere- has ✖️ language centres- BUT can draw picture of 🐈 with left 🖐 because right hemisphere controls this hand
Why did Sperry and Gazzaniga (1968) find what they did?
Because investigated split-brain patients where corpus callosum been severed- … ✖️ way for info presented to 1 hemisphere to travel to other
What are the evaluation points of Split-Brain Research?
👎- findings of split-🧠 research ✖️ be generalised to 🎯 population- disconnection between hemispheres greater in some patients than in others- ALSO some patients have drug therapy for epilepsy for much longer than others- may affect way in which 🧠 works
👎- many studies using split-🧠 patients have as few as 3 pps- … hard for results to be generalised
👎- in real world severed corpus callosum compensated for by unrestricted use of both visual fields (can look 👀 around) … research lacks ecological validity