WEEK 5- Biological Psychology. Flashcards
Caffeine, alcohol and nicotine changes the way you feel because they:
Change the chemistry of the brain.
Biological Psychology
Is the study of the cells and organs of the body, and the physical and chemical changes involved in behavior and mental processes.
The nervous system contains billions of cells that make up the brain, spinal cord and other nerve fibres. The combined activity of these cells tells you:
what is going on inside and outside your body and allows you to make appropriate responses.
The nervous system
- Is the combination of the Central Nervous System and the Peripheral Nervous System.
- Detects information and execute responses.
- Is made up of cells that communicate with each other.
The key function of the nervous system and body is:
The processing of information.
The nervous system’s three main functions are:
To receive information and gather information from the environment (input), integrate that information with past experiences (processing) and guide actions (output).
The nervous system is made up of two cells:
Neurons and Glial Cells.
Neurons
- Are cells that are specialized to rapidly respond to signals and to quickly send signals of their own, are anatomical structures.
- Nurons contains organelles such as mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus that support the daily functioning of the cell. Neurons are a special type of cell for neurotransmission.
Glial Cells
Are non-neuronal cells that performs important communication too, they are also specialized cells. They provide essential nutrients and growth factors needed for neurogenesis, as well as neuronal repair and maintenance. So, without glial cells, neurons could not function. Furthermore, glial cells are capable of the signature functions of neurons, including releasing chemicals that influence neurons, responding to chemicals from neurons, and changing in response to experience.
The human brain contains:
86 billion neurons
Soma
- Is the neuron cell body which is surrounded by a permeable cell wall and a nucleus holding the hosts DNA.
- All the information goes first to the soma (cell body) then it decides whether that neuron is sending information through the axon into its terminals.
Glial cells produce
Myelin.
There are 3 features that neurons share with almost every other kind of cell in the body which are:
- Neurons have an outer membrane that acts like a fine screen, letting some substances pass in and out while blocking others.
- Nervous system cells have a cell body which contains a nucleus (only red blood cells have no nucleus). The nucleus carries the genetic information that determines how a cell will function.
- Nervous system cells contain mitochondria, which are structures that turn oxygen and glucose into energy. This process is especially vital to brain cells.
Both neurons and glial cells are in charge of:
Processing chemical and electrical transmission of information within the nervous system.
The neuron structure comprises:
- Cell
- Cell membrane
- Dendrites
- Axons
- Ogliodendrocyte
- Node of Ranvier
- Myelin sheath
- Synapses
Axons
Tube-like structure that propagates the integrated signal away from the cell body and towards specialised endings called axon terminals. Each neuron has only one axon leaving the cell body, but one axon may have many branches.
Axon Terminal
Is where synapses with neighbouring neuron occurs. Located the end of an axon and typically synapse on other neurons, muscles or target organs. Axon terminals contain tiny parcels (vesicles) of neurotransmitters that are released in synapse.
Dendrites
Are fibers that receive signals from the axons of other neurons and carry those signals to the cell body. A neuron can have many dentrites. The dentrites have many branches.
Axons carry signals _____ from the cell body, whereas dendrites _________ from other cells.
Away; detect signals
Axon Hillock
Integrate signals from multiple synapses and serves as a junction between the cell body and an axon.
Synapses
Specialized junctions where transfer of signals occur, usually between the axon of one cell and the dendrite of another.
Neuronal membrane
A barrier that separates the inside of the neuron from the outside, which in cases the entire neuron
Action potential
Is an electrical impulse that travels down the axon and allows neurons to communicate.
Presynaptic neuron
The neuron transmitting the signal
Postsynaptic neuron
The neuron receiving the signal
The release of neurotransmitters which are chemical signals received by dendrites into the synapse is a process called:
Action potentials
The speed of the action potential depends on the
Diameter of the axon (larger ones are faster) and on weather myelin is present.
Myelin
Is a fatty substance that wraps around some axons and increases the speed of action potentials. Larger myelinated cells are usually found in parts of the nervous system that carry the most urgently needed information.
The disease Multiple Sclerosis is based on damaged
Myelin
A neurological disease affecting the output stage of processing is:
Parkinson disease
Nodes of Ranvier
Are gaps in the myelin sheath that allow the action potential to be propagated and regenerated (this is called saltatory conduction), here the signal is recharged as it travels along the axon.
The Saltatory Conduction
Allows for the action potential to travel extremely quickly along the axon – much faster than without the myelin sheath, where the action potential is required to be regenerated the whole way along the axon and is therefore slower and less energy-efficient
Refractory period
Is a short rest period between action potentials.
For communication to occur between cells, a signal must be transmitted across
The synapse, or gap, between neurons.
Neurotransmitters
Specialised neural chemicals released by neurons that are designed to cross the synaptic gap and bind onto cell receptors on another cell. These chemicals that assist in the transfer of signals from one neuron to another. These chemicals are stored in little bags called “vesicles“ at the tip of the axons.
Neural receptors
Cell surface proteins located within the cell wall that receive chemical signals.
______________ are involved in every aspect of behaviour and mental processes.
Neurotransmitters
Postsynaptic potential
Is the change in the membrane potential of a neuron that has received stimulation from another neuron.
Excitatory postsynaptic potential
Is a postsynaptic potential that depolarises the neuronal membrane, making the cell more likely to fire an action potential.
Inhibitory postsynaptic potential
Is a postsynaptic potential that hyperpolarises the neuronal membrane, making a cell less likely to fire an action potential.
For one neuron to communicate with another, a _____________has to cross the ____________between them.
Neurotransmitter; synapse.
In the brain and spinal cord, neurons are organized into groups called
Neural networks
Sensory system or senses
The groups of neurons in the nervous system that provide information about the environment (hearing, vision, taste, smell and touch).
Motor systems
Are parts of the nervous system that the brain uses to influence muscles and other organs to respond to the environment.
Central Nervous System (CNS) is composed of:
The brain and the Spinal Cord.
Brain in the CNS:
Interprets and stores information and send orders to muscles, glands and organs.
Spinal Cord in the CNS:
- Connects the brain and the Peripheral Nervous System.
- Relays signals from peripheral senses to the brain and conveys messages from the brain to the rest of the body
Cells of the spinal cord can direct some simple behaviours without instructions from the brain, these behaviours are called:
Reflexes, which are simple involuntary and unlearned. Ex, withdrawal of heat and knee jerk.
The surface of the brain is called:
Cerebral cortex
Parallel distributed processing
Is when information is processed by a number of brain regions at the same time.
A feedback system
- Are series of processes in which information about the consequences of an action goes back to the source of the action so that adjustments can be made. Ex, when you touch something hot, the arm contracts, if this does not happen, the feedback system appears.
- It also serves in the endocrine system as it regulates hormone secretion to keep it within a certain range. If a hormone rises above a certain level, feedback about this situation signals the brain and pituitary to stop stimulating that hormone’s secretion.
Limbic system
Is a complex set of brain structures that lies on both sides of the thalamus, just under the cerebrum. It deals with 3 key functions that are: emotions, memories and arousal (or stimulation).
The brain divides in:
Forebrain, Midbrain and Hindbrain.
Forebrain
Is the most highly developed part of the brain; it is responsible for the most complex aspects of behaviour and mental life. The forebrain has grown out of proportion to the rest of the brain as well as the cerebellum. The forebrain is a sensory relay for the brain. All of our senses, with the exception of smell, are routed through the thalamus before being directed to other areas of the brain for continued processing.
The major structures of the Forebrain are:
- Hypothalamus
- Corpus callosum
- Cerebral Cortex
- Striatum
- Thalamus
- Septum
- Amygdala
- Hippocampus
Midbrain
Is a small structure between the hindbrain and forebrain that relays information from the eyes, ears and skin an that controls certain types of automatic behaviors that control simple movements
The major structures of the Mindbrain are:
- Brain Stem
- Substantia nigra
Hindbrain
Lies just inside the skull and is actually a continuation of the spinal cord. So, signals coming from the spinal cord reach the hindbrain first. Blood pressure, heart rate, breathing and many other vital autonomic functions are controlled by nuclei in the hindbrain.
The major structures of the Hindbrain are:
- Reticular formation
- Locus coeruleus
- Cerebellum
- Medula oblongata
Thalamus
Is a brain structure responsible for relaying motor and sensory signals to other parts of the brain. Also, It relays pain signals from the spinal cord, as well as signals from the eyes and most other sense organs, to upper levels in the brain.
Hypothalamus
The hypothalamus regulates a number of homeostatic processes, including the regulation of body temperature and blood pressure. It regulates hunger, thirst and sex drive.
Amygdala
Is part of the limbic system that is involved in our experience of emotion and in binding emotional value to our memories and is associated with reward learning and regulates fear and arousal.
Structure of the limbic system
- Amygdala
- Hypothalamus
- Septum
- Portions of the cerebral cortex
Hippocampus
Is a part of the limbic system and is associated with the formations of new memories and is essential for the process of learning.
Septum
Regulates memories and emotions.
Brain Stem
Connects the cerebrum with the spinal cord. It coordinates and relays motor control signals sent between the brain and the body and controls life supporting functions of the nervous system.
The ____________nervous system transmits information from the senses to the_____________nervous system and then carries signals from the __________nervous system to the muscles that move the skeleton.
Somatic, central, central.
The _________nervous system carries messages back and forth between the __________nervous system and the heart, lungs and other organs and glands.
autonomic; central
Substantia nigra
Is an area of the midbrain involved in the smooth beginning of movement.
Striatum
A structure within the forebrain that is involved in the smooth beginning of movement.
What is the difference between the substantia nigra and striatum?
Substantia nigra is located in the midbrain and the striatum on the forebrain.
Reticular formation
Are collections of cells and fibres in the hindbrain and midbrain that involves the regulation of arousal and attention
Locus coeruleus
Is a small nucleus in the reticular formation that is involved in directing attention towards particularly important stimuli in the environment, and abnormalities have been linked to depression, attention deficit hyperactivity disorder, sleep disorders and post-traumatic stress disorder.
Cerebellum
Is the part of the hindbrain whose main functions include controlling finely coordinated movements and storing memories about movement. Its also involved in impulse control, pain, emotion, language and high order cognitive processes. It controls motor movement coordination, balance, equilibrium and muscle tone. It relays information between body muscles and areas of the cerebral cortex involved in motor control.
Damage to the cerebellum can result in:
Slow and uncoordinated movements and an inability to perform basic tasks such as walking.
Syndrome of cerebellar mutism
Is when surgery affects the cerebellum, in which patients become unable to speak for periods ranging from a few days to several years.
Medula oblongata
Is an area in the hindbrain that controls blood pressure, heart rate, breathing and other vital functions.
Peripheral nervous system (PNS):
Extends throughout the body and, like an email or instant messaging service, relays information to and from the brain. The PNS sends sensory information from the eyes, ears and other sense organs to the CNS. Also, it sends messages from the brain and spinal cord to the muscles, glands, and other parts of the body. The PNS is responsible for collecting sensory information processing in the CNS and also for enacting the motor commands received from the CNS.
For the PNS to accomplish his tasks, it has 2 subsystems that are:
Somatic and the Autonomic subsystem
The somatic subsystem of the PNS.
Transmits information from the senses, skin and muscles to the CNS and carries signals from the CNS to the muscles that move the skeleton.
It involves the sensory neurons that bring information into the brain. and the motor neurons that carry information from the brain to direct motion. These motor neurons extend from your spinal cord to the muscles.
The autonomic subsystem of the PNS.
Automatically regulates glands, internal organs, blood vessels, pupil dilation, digestion and blood pressure. It carries messages back and forth between the CNS and the heart, lungs and other organs and glands. This subsystem is influenced by the brain, and it controls activities that are normally outside conscious control such as digestion and perspiration (sweating). Disorders of the autonomic nervous system can make people sweat uncontrollably or faint whenever they stand up; they can also lead to other problems, such as an inability to have sex.
The autonomic subsystem of the PNS exercises his control through 2 subdivisions:
Sympathetic and Parasympathetic nervous system.
Sympathetic nervous system of the Autonomic (PNS).
Prepares the body to react and expend energy in times of stress. It mobilizes the body for action in the face of stress.
Fight-or-flight syndrome or fight–flight reaction.
The responses that result from intense activity of the sympathetic system. It readies the body for vigorous activity. Ex, animal encounter, in such a situation the sympathetic nervous system dilates the pupils, increases the heart rate and blood pressure, relaxes the bladder, signals the liver and adrenal glands to release more glucose and adrenaline (respectively) into the bloodstream. These physiological reactions in the body are designed to improve our body’s energy reserves and heighten our sensory capacity so that we can flee from danger or fend off a predator as required for our survival. The strength and speed of the sympathetic response helps an organism avoid danger.
Parasympathetic nervous system
Maintains body functions under ordinary conditions, saves energy. It allows someone to “rest and digest.” This system is associated with returning the body to routine, day-to-day operations.
Homeostasis
Is a state of equilibrium, in which biological conditions (such as body temperature) are maintained at optimal levels.
Thee Parasympathetic and Sympathetic nervous system have complementary functions how?
Maintaining the body’s homeostasis.
Cerebral Cortex
Is located on the forebrain. It is
divided by the cerebral hemispheres, anatomical and functional areas. Analyses sensory information; controls voluntary movements, abstract thinking and other complex cognitive activity
Cerebral Hemispheres
Are the left and right halves of the rounded, outermost part of the brain.
The ridges of the brain are called gyri and the valleys or grooves are called sulci or fissures. These gyri and sulci form important landmarks that allow us to separate the cerebral cortex into
Anatomical areas (Four lobes: the frontal, temporal, parietal and occipital lobe).
The most prominent sulcus, known as the longitudinal fissure is:
The deep groove that separates the brain into two halves or hemispheres: the left hemisphere and the right hemisphere.
Frontal lobe
Is involved in reasoning, motor control, emotion, and language. It contains the areas such as the motor cortex, the primary motor cortex. The frontal lobe also involves the prefrontal cortex, and the Broca area.
Motor cortex
Is involved in planning and coordinating movement.
Primary motor cortex
Commands all voluntary movements. it is highly specialised structure that localizes motor control for each body part and has an involved in movement, decision-making, problem solving and planning.
Broca Area is located in
The frontal lobe, specifically in the prefrontal cortex, which is responsible for for higher-level cognitive functioning and a language centre. The Broca area is essential for speech production.
The frontal lobe is divided by:
The prefrontal cortex, which is responsible for personality expression and the planning of complex cognitive behaviors; and the premotor and motor areas, which control the execution of voluntary muscle movement.
An injury to the frontal lobe can cause
Drastic changes in personality and social behavior such as becoming impulsive, irritable, aggressive, passive or withdrawn. Other symptoms include depression, lack of interest in activities and loss of the ability to judge what behaviors are socially inappropriate.
Temporal Lobe
Play an important role in organizing and combining what we see and hear, language and speech production, as well as memory association and formation. Structures of the limbic system, including the olfactory cortex, amygdala and the hippocampus are located within the temporal lobes.
Damage or injury to the temporal lobe
May alter behaviour and intellect rather than gross motor skills.
Wernicke’s area is located in______ and it involves:
In thee temporal lobe. Wernicke’s area is involved in the interpretation of both speech and written words. Damage to this area can leave a person able to speak, but it disrupts the ability to understand the meaning of words or to speak understandably.
Question: Tell me what to do with a cigarette.
Reply: Uh … uh … cigarette (pause) smoke it’.
Answer:
The person is suffering damage to the Broca area and is enduring Broca Aphasia, were the person has difficulty speaking, and what they say is often grammatically incorrect but the speech is meaningful.
Question: Tell me what to do with a cigarette.
Reply: ‘This is a segment of a pegment. Soap a cigarette’.
Answer:
Damage to the Wernicke’s Area. The person is suffering from Wernicke’s aphasia and what he is saying involves no meaning whatsoever but the speech is fluent.
Parietal Lobe
It is involved in the reception and processing of sensory information from the body. It controls goal directed voluntary movements, manipulation of objects and the integration of different senses that allows for understanding a single concept.
Occipital Lobe
Processes visual information, color recognition, depth and motion perception.
Damage to the occipital lobe can cause
Visual problems
Functional areas of the cerebral cortex
- Sensory Cortex
- Motor Cortex
- Association Cortex
- Visual Cortex
- Auditory Cortex
- Broca Area
- Wernickes Area
Sensory cortex
Lies in the parietal, occipital and temporal lobes. Is the part of the cerebral cortex that receives information from our senses.
Association cortex
is a part of the cerebral cortex that receive information from more than one sense or that combine sensory and motor information to perform complex cognitive tasks (Visual, auditory etc). It involves the Broca and Wernicke’s area.
Left Hemisphere
- When there is damage in this area, it produces impairments in the ability to use or understand language.
- Receives information from and controls movements of the right side of the body.
- Is where the language centers are, such as broca area and wernicke area.
- This hemisphere has better logical and language abilities than the right.
Right Hemisphere
- Receives input from and controls the left side of the body (the connections are contralateral, or opposite sided).
- This hemisphere is superior to the left hemisphere on tasks dealing with spatial relations (Ex, 3D shapes drawings) and recognizing human faces.
- Has better spatial, artistic and musical abilities.
Lateral dominance (lateralization):
Tendency for one cerebral hemisphere to excel at a particular function or skill compared with the other hemisphere. Lateralization is mainly regarding differences in language ability between cerebral hemispheres.
Split-brain patients
Are people who had undergone a surgical procedure in an attempt to control severe epilepsy. Before the surgery, their seizures began in one hemisphere and then spread to engulf the whole brain. As a last resort, surgeons isolated the two hemispheres from each other by severing the corpus callosum.
Corpus callosum
Is a massive bundle of fibres that connects the right and left cerebral hemispheres and allows them to communicate with each other, it consists on 200 m axons.
Neural plasticity
The ability to create new synapses and to change the strength of synapses. The brain’s ability to change, adapt, and reorganise itself. - Plasticity depends partly on neurons and partly on gial cells, and it provides the basis for the learning and memory processes.
Plasticity occurs throughout the:
Central Nervous System
Neurogenesis
Is the process of creating new neurons.
Suprachiasmatic nuclei
Is a part of a hypothalamus which keeps an approx. 24 hour clock that establishes your biological rythims such as walking and sleeping, as well as cycles of the body temperature.
The neurotransmitter system
Consists of a group of neurons that communicates using the same neurotransmitter.
The neurotransmitters used in the nervous system fall into three main categories, based in their chemical structure which are:
- Small Molecules (Acetylcholine, norepinephrine, serotonin, dopamine, glutamate and GABA).
- Peptodes (endorphines)
- Gases (Nitric oxide).
Acetylcholine
A neurotransmitter used by neurons in the peripheral and central nervous systems in the control of functions ranging from muscle contraction and heart rate to digestion and memory.
Norepinephrine/ Noradrenaline
Involved in learning, arousal, sleep and mood regulation.
Serotonin
Is involved with the regulation of sleep, mood and eating. Serotonin has also been implicated in aggression and impulse control and depression
Dopamine
Regulates movement and pleasure experience.
Malfunctioning of GABA systems contributes to a variety of disorders, including
Epilepsy, severe anxiety and Huntington’s disease
GABA
Affects sleep and movement
Glutamate
Is the major excitatory neurotransmitter in the central nervous system and affects memory
Which Neurotransmitter is used more by neurons?
Glutamate
Which Neurotransmitter reduces the likelihood that postsynaptic neurons will fire an action potential?
GABA
Cholinergic neurons
are neurons that use acetylcholine
Endorphines
Involves pain control
Nitric oxide neurotransmitter
Involves memory and penile erection.
Depression is associated with _______ and ________ Neurotransmitters
Serotonine and norepinephrine.
Endocrine system
Regulates functions ranging from stress response to physical growth. Made up of glands that communicate with each other via chemicals called hormones.
Glands
Are organs that secrete hormones into the bloodstream.
Hormones
Are chemicals secreted by glands into the bloodstream, which carries them throughout the body.
The norepinephrine and endorphins neurotransmitters act both as ___________ and ___________.
hormones; neurotransmitters.
Neurons release neurotransmitters into
____________ and endocrine organs release ____________, which carries them throughout the body.
synapces; chemicals into bloodstream.
Target organs
Are organs whose cells have receptors for hormones. Hormones, like neurotransmitters, can influence only cells with receptors capable of receiving them.
Major glands of the endocrine system:
- Pituitaty
- Pancreas
- Testes
- Hyphothalamus
- Thyroid
- Adrenal cortex
- Adrenal medulla
- Ovaries
Men have higher concentrations of __________ and women have higher concentrations of ____________.
Androgens; oestrogens.
The brain has ultimate control over the secretion of _________ and is one of the target organs for most endocrine secretions.
Hormones.
- The brain through the hypothalamus, it controls the pituitary gland, which in turn controls endocrine organs in the body.
The brain through the __________, it controls the ___________, which in turn controls ___________ in the body.
Hypothalamus, pituitary glands, endocrine organs.
The endocrine system involves four elements:
The brain, the pituitary gland, an endocrine organ and the target organs.
Adrenocorticotropic hormone (ACTH)
The brain interprets a situation as threatening, the pituitary releases adrenocorticotropic hormone (ACTH), which causes the adrenal glands to release the hormone cortisol into the bloodstream. These hormones, in turn, act on cells throughout the body, including the brain. One effect of cortisol, for example, is to activate the emotion-related limbic system, making it more likely that you will remember stressful or traumatic events.
Cortisol
Affects many different functions in the body. Cortisol can help control blood sugar levels, regulate metabolism, help reduce inflammation, and assist with memory formulation. It has a controlling effect on salt and water balance and helps control blood pressure.
Negative feedback system
After the immediate threat is over, feedback about cortisol’s action in the brain and in the pituitary stops the secretion of ACTH and, in turn, cortisol. Because the feedback suppresses further action, this arrangement is called a negative feedback system.
Neurons and _____________ are communication chemicals used within the human system and affect behaviour and mental processes
Hormones
The pituitary gland releases ___________, which causes the adrenal glands to release the________ hormone into the bloodstream
ACTH ; Cortisol
_______________systems are just one illustration of how the nervous system and the endocrine system are integrated to form the biological basis for a smoothly functioning self.
Feedback
Pituitary gland
The master gland, under control of the hypothalamus, that directs the other glands in the body. It regulates growth, controls the thyroid, ovaries or testes, pancreas and adrenal cortex; regulates water and salt metabolism.
Thyroid
Controls the metabolic rate.
Adrenal glands
Tissues located on top of the kidneys that release adrenaline and cortisol during states of emotional arousal (stress)
The right hemisphere gets information from the ___________ side of the body and has better ___________ abilities than the left hemisphere.
left; spatial