biopsych Flashcards
What is the localisation of function theory?
The theory that different areas of the brain are responsible for different behaviours.
What is hemispheric lateralisation?
The brain consists of two hemispheres connected by the corpus callosum with each hemisphere contributing to different functions.
What is the left hemisphere responsible for? [Bonus: What areas does it contain?]
The left hemisphere is responsible for language based functions. It contains Brocas area: Speech production and Wernickes area: Language processing.
What is the right hemisphere responsible for?
The right hemisphere is responsible for the recognition of emotions and spatial awareness functions.
What is the frontal lobe responsible for and what does it contain?
The frontal lobe is responsible for voluntary movement and higher executive functions.
It contains the motor cortex which regulates voluntary movements in logical order.
What is the temporal lobe responsible for and what does it contain?
The temporal lobe contains the primary auditory centre associated with processing sensory information.
What is the parietal lobe responsible for and what does it contain?
The parietal lobe contains the somatosensory centre where sensory information is processed to produce sensations such as pressure and pain.
What is the occipital lobe responsible for and what does it contain?
The occipital lobe contains the primary visual centre where it receives and processes visual information to understand things such as shapes and colours.
Where is Brocas and Wernickes area located?
Brocas area [speech production] is located in the frontal lobe [voluntary movement] and Wernickes area [language comprehension] is located in the temporal lobe [processing auditory information] .
How is localisation and lateralisation of the brain studied? Discuss how.
The brain is studied through case studies which are in-depth examinations of an individual or group.
Pros: Allows the study of unethical situations and more ecologically valid compared to laboratory experiments as it is conducted in real life situations.
Cons: Hard to generalise as they are often specific cases and therefore difficult to replicate and lack reliability.
Paul Broca & Leborgne [Evaluation support for localisation]
+Leborgne suffered from epilepsy and could only say the word TAN.
+His frontal lobe was damaged therefore an area was identified to be responsible for speech production.
+Modern time research identified more specific regions but the cause remained the same.
GR [Evaluation support for localisation + latersaliation]
+Developed blindness in her right visual field however had no damage in her eyes but only to the brain.
+When asked to detect a letter on the screen she could not identify what it was but was aware something was there.
+Concluded that she damaged her left visual centre in the occipital lobe. (Hemispheric lateralisation)
Karl Lashley 1950 [Evaluation challenge for localisation]
+Removed brain areas of the cortex in rats however found no specific area involved in learning, the function was spread around the brain.
+Looks at the brain holistically rather than each area being localised.
Herasty 1997 {Evaluation challenge for localisation theory]
Females have larger Brocas area and Wernickes area than in males meaning that they may have larger language capabilities.
+Localisation fails to take account of individual differences [ suffers from beta bias ]
+Suggests that more research needs to be conducted on separate genders
Neurosurgery {Evaluation support for localisation and lateralisation]
Neurosurgery is a positive application of the localisation and lateralisation theory as they take into account it for their procedures as it suggests that mental disorders are localised in the brain.
Economical implications involves providing more jobs for people and allowing more people to return to work via effective treatment.
How did Sperry 1968 investigate split brain research and what were the results?
He projected an image to the right visual field of a split brain individual and they were able to explain what they saw due to there being language centres in the left hemisphere however could not in the left visual field.
He asked participants to draw with the left hand and drew more accurately compared to the left as the right hemisphere is responsible for processing spatial information.
Gazzaniga [Evaluation support for split brain research]
Woman had a severed corpus callosum and was presented a nude woman in her left visual field and giggled however could not explain why. This is because her right hemisphere processed emotions but do not contain language centres to verbalise her emotions.
Outline and evaluate post mortem examinations
Post mortem examinations are the analysis of a deceased persons brain and comparing it to a neurotypical brain to establish a cause of mental disorders.
Pro: Broca and Wernicke relied on this technique before neuro- imaging to establish links between the brain and behaviour.
Cons: Correlation does not aways mean causation and it does not take into account of individual differences and has ethical issues.
Outline and evaluate fMRI
Also known as functional magnetic resonance imaging will track the energy released when haemoglobin binds to oxygen. Active parts of the brain will consume more O2 therefore can be identified during certain mental processes.
Pros: Produces dynamic 3D images to map how different parts of the brain interact during behaviours to understand localisation. Activity + Physiology.
Cons: Relies primarily on blood flow and does not consider electrical activity in the brain which is a important component in understanding the brain. Also very expensive and requires high expertise.
Outline and evaluate EEGs
EEGs measure general electrical activity of the brain by attaching electrodes directly to the brain to generate general wave patterns.
Pros: Contributed to the understanding of sleep cycles by being used in sleep laboratories and diagnosis of epilepsy.
Cons: Generates very general and non specific data therefore you cannot pinpoint the exact location of neural activity.
Outline and evaluate ERPS
ERPs are a type of EEG which can filter out extraneous brain activity to leave responses to a specific stimuli. This is linked to the identification of cognitive processes and used by cognitive neuroscientists.
Pros: Useful in testing research that suffer from social desirability. For example Costa, Brauna + Birbaumer used ERP to record male and female responses to nudes of opposite genders. Women stated they felt nothing however they had higher brain response when shown a nude of a male.
Cons: Not always easy to eliminate extraneous variables and can be difficult to conduct as it requires minimal movement.
What is plasticity in the brain?
Plasticity is the brains ability to change and adapt from experience and new learning. Often found to be the strongest during childhood, however recent research has found that even mature brains will continue to show plasticity.
Maguire et al [Evaluation support for plasticity]
Conducted MRI scans of taxi drivers vs non-taxi drivers and discovered that the area for spatial awareness and the amount of gray matter in the posterior hippocampus was larger in taxi drivers.
There was positive correlation between time in job and difference in brain structures.
Experience in taxi driving meant more information of routes and therefore different brains.
Kuhn [Evaluation support for plasticity]
Playing video games for 30 minutes per day increased the brain matter in the cortex, hippocampus and cerebellum.
This is because video games require complex cognitive requirements such as decision making and spatial navigation.
What is function recovery and how can it be boosted?
Functional recovery refers to the brains ability to recover after trauma as the unaffected areas of the brain will compensate for loss and damage. It is heavily induced by intensive rehabilitation by promoting the brains plasticity.
What happens during functional recovery?
During functional recovery, neural regeneration can occur where new nerve endings will grow and will connect to undamaged neural pathways to form new ones.
Homologous areas of the brain will be recruited to preform specific tasks, e.g opposite hemispheres.
Bezzola et al [Evaluation support for plasticity]
Plasticity is not limited to childhood. Receiving 40 hours of golf training in participants aged 40-60 years, by using an fMRI it was discovered that they had reduced motor cortex activity by creating more effective neural pathways.
What are the practical applications of functional recovery?
Has practical applications in neurohabilitation by professional being able to help with brain trauma through intensive rehabilitation as the brain cannot fully recover by itself.
Economic implications include providing for jobs for specialists in this field and more effective treatment for individuals with brain trauma.
Elbert et al [Evaluation challenge for functional recovery]
Found that capacity for neural regeneration is much greater in children than in adults meaning that it becomes less effective as you get older and therefore individual difference of age is very important when studying plasticity and functional recovery.
What are biological rhythms?
Biological rhythms are physiological processes of living organisms which occur in a cyclic manner that have implications in behaviour and mental processes.
What is the circadian rhythm?
The circadian rhythm is rhythm that follows a 24 hour cycle and is able to respond to light and darkness [ exogenous zeitgabers ].
What is an endogenous pacemaker and what are some examples in the sleep-wake cycle?
An endogenous pace maker are internal biological structures which maintain biological rhythms, for example..
The suprachismatic nucleus is a bundle of nerves located in the hypothalamus monitors the sleep wake cycle by acting as a biological body clock.
The pineal gland is another EP which secretes melatonin in the blood to induce sleepiness during the night.
Ralph et al [Evaluation support for EPs]
Removed the SCN out of genetically abnormal hamsters which had a circadian sleep wake cycle of 20hours and placed them into healthy rats and discovered that this disrupted their circadian rhythm.
Siffre [Evaluation support for EP and EZ]
He stayed in a cave in isolation in darkness with no EZ for 7 months. His 24 hour sleep-wake cycle increased by one hour suggesting that EZs do have an implications in biological rhythms but the body was aware when to sleep and eat without the regulation from EZ.
Artic sleep [Evaluation support for EP]
In the artic during the summer months the sun does not set however people living there still demonstrate a regular sleeping cycle. If primarily controlled by EZ they should technically not be able to sleep at all.
Campbell and Murphey [Evaluation support for EZ]
Monitored the body temperature of 15 volunteers who slept in a laboratory and found that when shining a light on their body it was able to disrupt their circadian rhythm by up to 3 hours showing the importance of EZ’s.
What are some strengths and weaknesses from the research of circadian rhythms?
Strengths: It gives us understanding of adverse consequences from disruption and desynchronisation of the sleep cycle. Economical implication include providing a better work environment for workers so they can work for longer and choosing peak times to take medicine.
Weaknesses: Sleep/Wake studies are usually done on small groups of individuals or one person making their generalisability bad.
Does not consider individual differences [ Night owl and Larks ]
Monitoring sleep patterns can affect research [ Campbell and Murphey ]
Krutsson et al [Evaluation implication of night shift workers]
Found that participants who did night shift work for more than 15 years were 3x more likely to develop a heart disease than non-shift workers due to the desynchronisation of rhythms leading to growth hormones not working as well.
What is an infradian rhythm? Give an example.
A biological cycle which lasts longer than 24 hours which could be weekly, monthly or yearly. For example the menstrual cycle.
What is SAD? How can you treat SAD?
SAD, season affective disorder, is a type of infradian depression which occurs during winter months, linked to the shorter days meaning less light. This means that more melatonin is produced and less serotonin is released. You can treat SAD by light therapy to imitate morning light.
What are pheromones?
Pheromones are a chemical substance released by an animal which affect the behaviour/physiology of another animals. They can affect infradian rhythms.
Reinberg 1967 [Evaluation support for EPs effect on infradian rhythms]
Had female participants spent 3 months in a cave with a small lamp as a light source. Their circadian rhythm lengthened however the menstrual cycle was reduced by a few days meaning that light may have an affect in monitoring infradian rhythms.
McClintock & Stern [Evaluation for pheromones] What does it show?
Females who had smelled the pheromones acquired from the armpits from other women who where near the end of their cycle had their menstrual cycle shortened and vise versa with the opposite effect.
This research helps us understand menstrual synchronicity for example uni flats and in tribes which provide an evolutionary advantage [sharing motherly responsibilities]
What are ultradian rhythms?
Biological rhythms that last less than 24- cycles, e.g the sleep cycle not to be confused with the sleep-wake cycle.
What are the stages of the sleep cycle and how are the stages of sleep monitored?
The five stages of the sleep cycle are separated by different types of waves and associated with different types of activities.
The stages of sleep are studied by EGGs and conducted in sleep laboratories.
1-4 Stages are NREM associated with the gradual less activeness of the brain where brain activity and blood pressure is decreased.
REM is stage 5 with the highest brain activity and where dreams are most active [Dement & Kleitman]
Dement and Kleitman [Evaluation for sleep cycle]
Dement and Kleitman monitored sleep patterns in 9 individuals using EEGs and found that the REM stage was the highest associated with dreaming.
