Biopsychology

found in receptors such as the eyes, tongue and skin. carry impulses from the pns to the spinal cord and the brain. impulse translated into sensations when reach brain such as touch. have long dendrites short axon AND CELL BODY. not all sensory neurons reach brain, some stop at spinal cord allowing quick reflex actions

only found in the brain/visual system/spinal cord connect sensory neurons to motor or other relay neurons. have short dendrites and short axon.

carry messages from cns to control muscle movements. when stimulated, these neurons release neurotransmitters that bind to receptors on the muscle triggering muscle movement long axon short dendrites.

Sensory neurons send information from the senses to the brain – here receptors in x would sense x and send that information via the peripheral nervous system to the brain/CNS. Relay neurons connect with other neurons, mostly found in the brain/CNS - here they would be involved in analysis of the sensation, what it means, deciding about how to respond to it, thus acting between the sensory and motor neurons. * Motor neurons send messages via long axons from the brain to the muscles or effectors – here the message from the brain instructs x

(process of transmitting msgs from neuron to neuron.) electrical impulse travels down the axon of a presynaptic neuron, reaching presynaptic terminal. electrical impulse triggers release of neurotransmitters from vesicles within presynaptic neuron. neurotransmitters cros the synapse from vesicles by diffusing between gap. neurotransmitters combine with receptors on the post synaptic membrane, stimulating post synaptic neuron to transmit electrical impulse down its axon to next neuron. results in either excitation or inhibition of the post synaptic membrane.

neurotransmitters can be excitatory or inhibitory. if the neurotransmitter is excitatory then the post synaptic neuron is more likely to fire an impulse as it increases its positive charge. if a neurotransmitter is inhibitory, then the post synaptic neuron is less likely to fire as it makes it more negatively charged.

Nervous system (provides biological basis of psychological experience) ^ ^ peripheral NS central NS (transmits info to concernedw and from centralNS)lifefunctions psychprocesses ^ ^ spinal cord brain recieves/transmits info)maintain to and from brain) life,psychproc ^ somatic ns transmits sensory info from body receptors to brain transmits ifno from brain to muscles. controls skeletal muscles ^ autonomic transmits info to and from internal organs to sustain life processes. controls muslces ^ ^ sympathetic parasympathetic increases bodily maintains/ activites decreasesbodily activities

made up of brain and the spinal cord. brain involved in psychological processes. outer layer cerebral cortex distinguishes our higher mental functions from animals. spinal cord extension of brain. responsible for relaying information between the brain and the rest of the body

function is to relay nerve impulses from the cns to the rest of the body and from thee body back to the cns. subdivided into somatic nervous system - transmits information from the brain to muscles to produce voluntary movements controls controls skeletal muscles. integrates the brain with the outside world autonomic nervous system - governs vital functions in the body such as breathing, digestion. subdivided into sympathetic - increases bodily activites parasympathetic - maintains/ decreases bodily activites.

helps regulate cell and organ activity within the body and control vital physiological processes in the body releases hormones from glands into the bloodstream which then bind with specific receptors in order to regulate the activity of cells or organs in the body major glands Pituatory, pineal, adrenal, reproductive organs(testes ovaries) and thyroid. imbalance in hormones might lead to dysfunction for example, high levels of cortisol causing Cushing’s disease.

Pituitary gland - the master gland which releases ACTH. causes other glands to secrete their hormones or directly produces effects Pineal gland - melatonin - regulates the sleep wake cycle. high levels of melatonin causes drowsiness when daylights low. Adrenal gland - adrenaline - causes physiological changes such as increased heart rate by triggering the fight or flight mode in response to a stressful situation. Ovaries - oestrogen/progesterone- helps regulate menstrual cycle. oestrogen thickens uterus lining pro maintains it Testes - testosterone- secondary sexual characteristics eg facial hair, deeper voice. Thyroid - thyroxine - increases metabolic rates and affects growth

when we experience an acute stressor, hypothalamus prepares the body for emergency response by activating the sympathetic branch of the ANS to send neurotransmitters to the adrenal medulla. this releases adrenaline. this increases blood flow and pressure and glucose for respiration. decreases digestion. switches from parasympathetic to sympathetic activity and back again. enables a quick reaction to fight the threat or run away from it

issue with this explanation is that it doesn’t fully explain the stress response in females. Taylor et al. suggest that females adopt a ‘tend and befriend’ response in stressful/dangerous situations: Women are more likely to protect their offspring (tending) and form alliances with other women (befriend), rather than fight an adversary or flee. This highlights a beta bias within this area of psychology: psychologists assumed that females responded in the same way as males until Taylor suggested otherwise. Therefore, while the original fight or-flight explanation may have been limited in its application to females, it has prompted more recent research which has provided an alternative explanation more relevant to females, which is actually a strength. A strength is that the fight or flight response allows us to be more wary of our environment during dangerous situations. This was seen in Yuille and cutshalls study, where they interviewed 13 ps 4-5 months after a real shooting in Canada. they found they had good ewt, especially w high anxiety- 88% comapred to 75%. shows that the fight or flight One limitation to the fight-or-flight explanation is that human behaviour is not limited to only two responses.Gray (1988) suggests that the first response to danger is to avoid it altogether, which is demonstrated by a ‘freeze’ response. During the freeze response, humans are hyper￾vigilant while they appraise the situation to decide the best course of action. This suggests that the fight-or-flight explanation of behaviour is limited and doesn’t fully explain the complex cognitive and biological factors that underpin the human responses to stress/danger

the idea that specific functions have specific locations in the brain. therefore if specific area damaged, associated function affected.

auditory centre in each hemisphere. receives info from both ears about sound. damage ,may produce partial hearing loss, more extensive damage more extensive loss. LEFT TEMPORAL lobe- wernicks area- comprehending language.

movement centres on the motor cortex which sends msgs to muscles. generates voluntarily motor movements. next to this is somatosensory which perceives touch. LEFT FRONTAL LOBE- brocas area- speech production damage - slow slurred speech

visual cortex. back of the brain. responsible for processing visual information. each eye sends info from right visual field to the left visual cortex and opposite.

strength supporting evidence. a man could only say the word tan. his autopsy showed a lesion in a region of his brain in left frontal lobe. Broca concluded tans inability to speak was caused by damage to this region and this particular area controlled speech. this region now renamed as brocas area. inc validty neg is that theres evidence to show hemispheric lateralisation in the brain. Fink used pet scans to identify which brain regions were active during a visual processing task. wheen ps were asked to attend to global elements of an image regions of the right hemisphere were more dominant. when asked to focus in on the finer detail specific areas of the left hemisphere were more dominant. suggests tasks such as visual processing are feature of connected brain. supports idea that cognitive functions involve coordination between different regions of the brain rather than strict localisation as diff aspects of the task activate diff areas across both hemispheres. neg- evidence from brain plasticity fails to support localisayion of a function. when brain dmaged through an illness/accident and particular function lost, the rest of brains able to reorganise itself to recover the function. Turk et al discoverede p who suffered damage to his left hemisphere but developed capacity to speak in the right hemisphere. suggests that functions arent localised, brain can adapt following damage to certain areas. challenges theory of localisation showing brain can adapt following damage to certain areas

idea that the 2 halves of the brain are functionally different and that mental processes and behaviours are mainly controlled by one hemisphere rather than the other. 2 hemispheres bridged by corpus callosum(bridge, bundle of fibres, is a communication pathway so both hemispheres can exchange info) contralateral. - left hemisphere deal w right side of body rigth hemisphere left

left - mainly language processing. logic. broca and wernicke ereas found ehre, which is y ppls speech affected if they have stroke on left side of their brain right - creativity. dominant for facial recognition

strenght theres evidence to show hemispheric lateralisation in the brain. Fink used pet scans to identify which brain regions were active during a visual processing task. wheen ps were asked to attend to global elements of an image regions of the right hemisphere were more dominant. when asked to focus in on the finer detail specific areas of the left hemisphere were more dominant. suggests tasks such as visual processing are feature of connected brain. supports idea that cognitive functions involve coordination between different regions of the brain rather than strict localisation as diff aspects of the task activate diff areas across both hemispheres. neg- evidence from brain plasticity fails to support lateralisation of a function. when brain dmaged through an illness/accident and particular function lost, the rest of brains able to reorganise itself to recover the function. Turk et al discoverede p who suffered damage to his left hemisphere but developed capacity to speak in the right hemisphere. suggests that functions arent laterialised, brain can adapt following damage to certain areas. challenges theory of lateralisation showing brain can adapt following damage to certain areas neg- lateralisation may be complicated by age. research has shown lateralisation of function may change throughout an individuals lifetime. Evidence for this comes from Szflarski who found that language became more lateralised to the left hemisphere as children developed into adolesents but after 25 lateralisation decreased with each decade of life. problem as suggests more hemispheric lateralisation much more complex process than many realise.

Sperry studied 11 split brain patients who had their corpus callosum cut due to severe epilepsy. verbal recognition- picture was presented to the left visual field which processed by right hemisphere. ps asked to describe what they saw. repeated using right visual field. touch recognition- patients hands screened so they couldnt see objects infront of them. ps asked to pick up and object with their right hand, processed left hemisphere, asked to describe what theyd felt. repeated using left hand.

verbal recognition - when picture of object shown to patient right visual field the patient could decribe what they had seen. left visual field - could not describe what they saw and reported nothing. bc language processed left hemisphere, not processed right hemisphere. touch - ps couldnt verbally describe objects projected in their left visual field, able to select a matching object from a grab bag using left hand, left hand selecting object most closely assosciated to original.