Key Studies and Vocabulary - BIOLOGICAL Flashcards
Why is Phineas Gage important to understanding the structure and functioning of the brain?
Phineas Gage was a railway worker who received a substantial brain injury when an explosion caused a metal bar to be shot through his head. He survived, but suffered damage to the right frontal lobes of his brain. Gage’s personality changed following the injury. He became more impulsive and there was some memory impairment. This led later researchers to conclude that specific brain areas were responsible for specific psychological functions, an idea we now know as ‘localisation of function’.
Why is Broca (1861) important to understanding the structure and functioning of the brain?
Broca (1861) studied a patient (‘Tan’) who was unable to speak. ‘Tan’ died, and during post-mortem examination, Broca discovered that Tan had an area of brain damage in his left frontal lobe. He concluded that the ability to speak is linked to that specific region, adding weight to the idea that function is localised in the brain. This region is still referred to as ‘Broca’s area’ and patients who understand language but cannot speak are said to have ‘Broca’s aphasia’.
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define neuron
one of the cells that make up the nervous system.
define nervous system
the network of signalling cells throughout the body, responsible for organising behaviour.
define central nervous system
the brain and the spinal cord.
define hind brain
a set of brain structures at the top of the spinal cord, mainly dealing with survival functions like breathing, heartbeat and consciousness.
define midbrain
a set of brain structures above the hindbrain, mainly responsible for movement and for homeostasis (keeping the internal environment stable).
define limbic system
a set of brain structures linking the midbrain and the forebrain, mainly responsible for emotional responses including fear and anger. It plays an important role in aggression.
define forebrain
a set of brain structures in the upper and outermost parts of the brain. It includes areas important for ‘higher’ mental functions like thinking, language and memory.
What research methods are used to understand the structure and functioning of the brain?
Brain scanning
Studies using animal models
Why is Raine et al. (1997) important when using scanning to understand the brain?
Raine et al. (1997) used PET scans to compare murderers with ordinary people. They found that the murderers had different patterns of brain activity in the forebrain and the limbic system.
Why is Hirvonen et al. (2011) important when using scanning to understand the brain?
Hirvonen et al. (2011) used PET scans to show that long-term users of cannabinoid drugs show changes to the brain.
Why is Gazer et al. (2000) important when using scanning to understand the brain?
Gazer et al. (2000) used MRI scans to show that schizophrenia patients had reduced volumes of brain tissue compared to a comparison group
Why is Carlsson et al. (2000) important when using scanning to understand the brain?
Carlsson et al. (2000) used a range of studies, including brain imaging to show that schizophrenia is related to abnormalities in brain systems that use dopamine and glutamate as their main neurotransmitter.
Define brain scanning/imaging
using technology to produce images of brain structure and/or activity without needing to open up the skull.
Define CAT scan
an imaging technology that uses X-rays to generate pictures of brain structure.
Define PET scan
an imaging technology that generates images of brain activity by tracing the uptake of glucose in different brain areas.
Define fMRI scan
an imaging technology that generates images of brain structure and activity by tracking the movement of water/blood in different brain areas.
Define spatial resolution
how much fine detail is presented in the scan image. A scanner with a higher spatial resolution shows a more detailed image.
Define temporal resolution
how well the scanner tracks changes in brain activity over time. A scanner with a higher temporal resolution is more responsive to short-term changes in brain activity.
What research methods are used when trying to understand how brain scanning is used to understand the brain?
Brain-scanning techniques (CAT, PET and fMRI)
Why is Ramon-y-Cajal (1894) used to understand neural transmission?
Ramon-y-Cajal (1894) was the first scientist to describe the structure of neurons in detail. It had previously been believed that the brain consisted of a continuous network of tissue. Ramon-y-Cajal discovered that each neuron was a separate cell, not joined directly to any others. He concluded that each neuron must be capable of both (1) transmitting signals within itself; and (2) sending signals to other neurons. This discovery underpins all of modern biopsychology and neuroscience.
define neuron
the main cell of the nervous system
define action potential
the electrical signals that are sent from the dendrites to the terminals of a neuron.
define dendrites
the tree-like structures that receive signals from other neurons.
define axon
the long, branching structure that transmits the action potential to the terminal, allowing neural signals to be sent over (potentially) long distances.
define terminal
the structure where action potentials finish, and chemical signals are sent to other neurons.
define myelin sheath
a fatty substance wrapped around the axons of some neurons. It allows action potentials to travel faster.
define ions
charged particles. The movement of ions allows the action potential to happen.
define firing rate
the frequency with which a neuron produces action potentials. A neuron’s firing rate increases or decreases in response to the signals it receives from other neurons at its dendrites.
What research methods are used to understand neural transmission?
The use of animals in psychological research: most of what we know about neurons and neural transmission we learned by experimenting on the neurons of giant squid.
define synapse
the junction between two neurons
define synaptic transmission
the process in which one neuron signals to another neuron to increase or decrease its firing rate.
define presynaptic membrane
the end structure of a neuron, where action potentials stop, and chemical signals are sent out.
define postsynaptic membrane
the areas on a neuron’s dendrites, where chemical signals are received from other neurons.
define synaptic gap
the space between the presynaptic and postsynaptic membrane. It is filled with fluid.
define neurotransmitters
chemicals that convey a message from the presynaptic to the postsynaptic neuron
define vesticles
tiny ‘bubbles’ inside the presynaptic terminal where neurotransmitter is held before release.
define reuptake
a process in which excess neurotransmitter it taken back into the presynaptic terminal and recycled.
what research methods are used to understand synaptic transmission?
Studies using non-human animals have been used to understand the basic processes of synaptic transmission.
Why are Olds and Milner (1954) considered in recreational drugs and synaptic transmission?
Olds and Milner (1954) wired rats to an apparatus which, when the rat pressed a level, would deliver electrical stimulation to part of the rat’s brain (the septal area). They found that the rats would repeatedly press the button, ignoring other possible rewards (e.g. food and drink) until they collapsed from exhaustion. This led to the discovery of the reward pathway, which we now know to be involved in why people take recreational drugs. Much of the reward system relies on dopamine as its main neurotransmitter
define drug
a substance put into the body deliberately in order to change its functioning.
define psychoactive drug
a substance that changes the functioning of the brain, bringing about changes in thinking, feeling and behaviour.
define recreational drug
a psychoactive drug taken for non-medical reasons, because the user wants or needs to feel the effect.
