Assessment 3 BIOPSYCHOLOGY Flashcards
Autonomic and somatic nervous system
1
What are the two components of the nervous system?
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
What is the PNS split into?
Somatic nervous system
Autonomic nervous system
What is the autonomic system then split into?
Sympathetic NS
Parasympathetic NS
What is the voluntary and conscious control system?
Somatic nervous system
What does the somatic nervous system contain?
- Made up of 12 pairs of cranial nerves and 31 pairs of spinal nerves.
- Contains sensory + motor neurons that control skeletal muscles like joints.
- Involved in reflex actions without the involvement of the CNS, which allows the reflex to occur very quickly.
What is the autonomic nervous system and what does it contain?
-Unconscious thought/actions.
For example controls heartbeat
Adjusts and maintains body’s internal environment
Fight or flight response
1
What does the amygdala do in fight-or-flight responses?
The part of the brain that is triggered in fight-or-flight responses. Associates sensory signals with emotions associated with fight-or-flight such as fear.
How does the amygdala communicate with the hypothalamus in the fight-or-flight response?
Sends a distress signal to hypothalamus which then communicates to the rest of the body via the sympathetic NS for a response.
What are the two major stress reponses? and their meanings..
Acute (sudden) stressors such as a personal attack.
Chronic (ongoing) stressors such as a stressful job.
What does the SNS then do after hypothalamus has called it because of the amygala? and then what does the adrenaline do?
Adrenaline Sends signal to adrenal medulla to release adrenaline into blood.
Circulates body, affecting target cells, heart beats faster to push blood to the muscles and heart. Blood pressure and breathing rate increases. Release of glucose + fats to provide supply for energy
What does the PNS do after the fight-or-flight response?
Once the threat has gone, autonomic nervous system dampens down stress responses causing a decrease in heart rate and blood pressure and digestion begins again.
How does the brain respond to chronic stressors?
If brain continues to perceive something threatening the second system kicks in. Hypothalamus activates the HPA axis.
What does the abbreviation HPA stand for?
Hypothalamus
Pituitary gland
Adrenal glands
What does the H P A axis do?
Hypothalamus - stimulates (CRH) into the blood.
Pituitary gland - CRH causes pituitary to produce + release ACTH targetting cells in adrenal glands
Adrenal gland - ACTH stimulates adrenal cortex to release various stress hormones including cortisol causing a positive effect - a burst of energy.
What is the ‘tend and befriend’ evaluation point in fight or flight response
Taylor et al (2000) suggests for females, responses to stress are due to tend and befriend than fight or flight.
Involves protecting themselves/young ones through nurturing behaviours (tending) and forming protective alliances (befriending).
They may have a different strategy to coping with stress because of the context of being the caregiver of the child.
What are the negative consequences of the fight or flight response - eval point.
Stress of modern life rarely require such levels of physical activity - problem arises when response is repeatedly activated eg: increased B.P, a characteristic of SNS activation can lead to physical damage.
Fight or flight does not tell the whole story - eval point.
Gray (1988) aruges first phase of reaction to a threat is not to fight or flee but to avoid confrontation - animals often display ‘freeze responses’ - not included.
Localisation of function
1
What is localisation of function?
Localisation of function means that specific functions (language, memory, hearing, etc) have specific locations within the brain.
What is the motor cortex’s primary function?
Responsible for generation of voluntary motor movement.
Where is the motor cortex located in the brain? (what does each bit control?)
Frontal lobe in both the left and the right hemisphere - With the motor cortex on one side of the brain controlling the muscles on the other side of the body.
What is the somatosensory cortex’s primary function?
Detects sensory events arising from different regions of the body
Where is the somatosensory cortex located in the brain?
Again is on the opposite side of the brain to the side of the body affected
Parietal lobe.
What is the visual cortex’s primary function?
Colour / shape of movement
Where is the visual cortex located in the brain?
Occipital lobe of the brain.
Visual cortex spans both hemispheres, receiving information from opposite sides of the body again e.g. right hemispheres receives impulse from left retina.
Begins in retina.
What is the visual cortex’s primary function?
concerned with hearing.
Where is the auditory cortex located in the brain?
Temporal lobes on both sides of brain.
Pathway begins in the cochlea in the inner ear where sound waves are converted into nerve impulses, which travel up auditory nerve.
Who was Broca and what did he do?
Broca’s area name after Paul Broca, French neurosurgeon who treated a patient who he referred to as ‘Tan’ as that is the only syllable this patient could express.
What is Broca’s area primary function?
concerned with speech
Where is Broca’s area located in the brain?
Posterior portion of frontal lobe - mainly left hemisphere
Who was Wernicke and what did he do?
Carl Wernicke, German neurologist, discovered area involving the understanding of language.
What is Wernicke’s area primary function?
understanding of language.
Where is Wernicke’s area located in the brain?
posterior portion of left temporal lobe.
What are the challenges to localisation: equipotentiality in the localisation of function.
Not all researchers agree with the view that cognitive functions are localised in the brain. Lashley (1930) believed basic motor and sensory functions were localized - but following injury the intact areas of the cortex could take over responsibility.
What is the support for language centres from aphasia studies in localisation of function Eval point.
Broca’s and Wernicke’s areas come from the discover that damage to these different areas results in different types of aphasia.
Expressive (Broca’s) aphasia, an impaired ability to produce language. Most cases caused by brain damage.
Receptive (Wernicke’s) aphasia impaired ability to understand language. Usually result from stroke.
What is communication may be more important than localisation in localisation of function. Eval point.
Research suggests what might be more important is how brain areas communicate with each other, rather than what controls each specific process. Dejerine describes a case where there was a loss of the ability to read in a patient because of damage to connection between visual cortex and Wernicke’s area.
Ways of studying the brain
1
What is a post-mortem examination?
Used to establish the cause of death
Establish the underlying neurobiology of a particular behaviour
Give an example of a post-moterm examination - how it can help study the brain.
Broca’s work with patient, Tan, who displayed speech problems when alive and was subsequently found to have a lesion in the area of the brain now known as the Broca’s area.
1 strength of a post-mortem examination.
- Allow for more detailed examination of anatomical neurochemical aspects of the brain.
- Harrison (2000) claims post-mortem studies have played a central part in our understanding of the origins of schizophrenia.
1 weakness of a post-mortem examination.
- People die in a variety of circumstances, varying stages of disease - factors that can influence post-mortem.
- Limited as the person is dead - Tf researcher unable to follow up on anything from post-mortem.
What is a functional magnetic resonance imaging (fMRI)
technique for measuring changes in brain activity while a person performs a task.
-It does this by measuring changes in blood flow in particular areas of the brain, which indicates increased neural activity in those areas. -If a particular area of the brain becomes more active, there in an increased demand for oxygen in that area. -The brain responds to this extra demand by increasing blood flow, delivering oxygen in the red blood cells. -As a result of these changes in blood flow, researchers are able to produce maps showing which areas of the brain are involved in a particular mental activity.
Give 1 strength of an fMRI scan.
- Noninvasive, does not involve insertion of instruments into body.
- More objective + reliable measure than verbal reports
Give 1 weakness of an fMRI scan.
- Changes blood flow in brain
- Overlooks networked nature of brain activity
What is an electroencephalogram (EEG)
Measures electrical activity in the brain.
Electrodes placed on scalp detect small electrical charges resulting from the activity activity of brain cells. When electrical signals from the different electrodes are graphed over a period of time - result is an EEG.
EEG data is useful for: detecting brain disorders (epilepsy)
4 basic EEG patterns are alpha, beta, delta and theta waves:
Awake but relaxed = Rhythmical Alpha. Psychologically aroused and sleep when eyes move back and forth rapidly = Low Amp / Fast frequency Beta
Delta + Theta are also sleep
Give 1 strength of an EEG.
- Provides a recording of the brains activity in real time, therefore a researcher can accurately measure a particular task
- It is useful in clinical diagnosis
Give 1 weakness of an EEG.
- It cannot reveal what is going on in deeper regions of the brain because it only detects the superficial regions
- Electrical activity can be picked up by neighbouring electrodes, therefore the EEG signal is not always that exact
What is an event-related potential?
Event-related potentials (ERPs) are very small voltage changes in the brain that are triggered by specific events or stimuli. ERPs are difficult to pick out from all other electrical activity being generated within the brain at a given time. To establish a specific response to a target stimulus requires many presentations of the stimulus and these responses are then averaged. Any other neural activity that is not related to the specific stimulus will not occur consistently, whereas activity linked to the stimulus will.
Give 1 strength of an event-related potential (ERP).
Can measure the processing of stimuli even in the absence of a behavioural response. ERPs can record covertly
Give 1 weakness of an event-related potential (ERP).
- ERPs are so small and difficult to pick out from the other electrical activity in the brain. Requires a large number of trials to gain meaningful data.
- Only sufficiently strong voltage changes across the scalp are recordable.
