PSYC*2650 Chapter 2: The Neural Basis for Cognition Flashcards
What is Capgras Syndrome?
Disorder resulting in an individual being able to recognize people in their world, although convinced that they are not who they appear to be (ex. replaced by a fraud who looks like them)
Damage to which brain regions are associated with Capgras?
- Temporal lobe, disrupts circuits involving the amygdala
- Prefrontal cortex
What is the neural basis for Capgras Syndrome?
- People with Capgras experience an intellectual identification when seeing a familiar face, but lack the emotional appraisal (created by amygdala) that typically accompanies it
- They also lack reasonable thinking and the ability to keep track of reality (prefrontal cortex)
Which brain disorder was influential in coming to the conclusion that many different brain areas are needed for simple achievements?
Capgras Syndrome
What is localization of function?
The study of what specific job is performed by a particular region of the brain
What is neuropsychology?
The study of the brain’s structures and how they relate to brain function
What is clinical neuropsychology?
- A specialty within neuropsychology
- Seeks to understand the functioning of undamaged brains by studying cases involving brain damage
What are neuroimaging techniques?
Non-invasive methods for examining either the structure or activation pattern within a living brain
What are the two types of images that can be produced by neuroimaging techniques?
- Structural imaging
- Functional imaging
How is a computerized axial tomography (CT scan) performed?
- Detectors placed around a person’s head
- Data is interpreted by computer to create 3D map of brain anatomy
Do CT scans provide structual or functional images?
Structural
How is a positron emission tomography (PET scan) performed?
- Low dose of radioactive glucose is injected into patient
- Detectors placed around the head track which brain areas use the glucose
- Computer creates a 3D map of activation levels
Do PET scans provide structural or functional images?
Functional
How is magnetic resonance imaging (MRI scan) performed?
Uses magnetic fields created by radio waves to construct a 3D representation of the brain
Do MRI scans provide structural or functional images?
Structural
What does functional magnetic resonance imaging measure (fMRI scan)?
Measures oxygen content in blood flowing through each brain region
Do fMRI scans provide structural or functional images?
Functional
Does fMRI imaging provide high or low spatial resolution?
High
Does fMRI imaging provide high or low temporal resolution?
Low
Communication between neurons involves what type of signalling?
Chemical signals
T or F: Communication within neurons involves chemical signals.
False. Involves Electrical pulses.
What do electroencephalograms (EEG) record?
The voltage changes occurring at the scalp, which reflect brain activity underneath.
Do EEGs provide high or low spatial resolution?
Low
Do EEGs provide high or low temporal resolution?
High
What neuroimaging technique is often used to study broad rhythms in brain activity?
EEGs
What are the three main types of broad rhythms recorded by EEGs?
- Alpha rhythms
- Delta rhythms
- Gamma rhythms
Which type of EEG rhythm is usually detected when awake and calm?
Alpha rhythms
Which type of EEG rhythm is usually detected when deeply asleep?
Delta rhythms
Which type of EEG rhythm is suggested to play a key role in creating conscious awareness?
Gamma rhythms
What are event-related potentials?
Changes in an EEG in the brief period just before during, and after an explicitly defined event
What are three ways in which the brain can be manipulated to observe how changes affect functioning?
- Chemicals
- Stimulation of specific sites
- Manipulation of genes
Do neuroimaging techniques provide information on correlation causation?
Correlation
Which brain area that is especially active when a face is being perceived?
The fusiform face area
What is often argued about the fusiform face area?
Whether it is needed for facial perception, or simply a by-product
What “other data” is needed to determine if a brain site actually causes a function?
Brain lesions
What is transcranial magnetic stimulation (TMS)?
Technique using strong magnetic pulses at a specific location to temporarily disrupt the brain region underneath
What are two ways transcranial stimulation can be used to observe brain function?
- Stimulate certain neurons
- Disrupt certain neuron and cause temporary lesions
What is included in the central nervous system?
The brain and spinal cord
What is included in the peripheral nervous system?
All aspects of the nervous system, excluding the brain and spinal cord
What are the two subcategories of the peripheral nervous system?
- Autonomic nervous system
- Somatic nervous system
What is the difference between the autonomic and somatic nervous systems?
- Autonomic: Regulates involuntary bodily processes
- Somatic: Controls voluntary movements
What are the two subcategories of the autonomic nervous system?
- Sympathetic nervous system
- Parasympathetic nervous system
What is the difference between the sympathetic nervous system and the parasympathetic nervous system?
- Sympathetic: Prepares the body for action and stress (fight or flight)
- Parasympathetic: Calms the body and helps conserve energy
What are the three main structures of the brain?
- Hindbrain
- Midbrain
- Forebrain
What are the three main components of the hindbrain?
- Cerebellum
- Pons
- Medulla
What is the cerebellum mainly responsible for?
Coordination of body movements and balance
What is the role of the pons?
Provides the main connection between the cerebellum and the rest of the brain
What is the role of the medulla?
Control of vital functions like breathing and heart rate
What are three major functions of the midbrain?
- Coordination of eye movement
- Relay of audio information from ears to forebrain
- Regulation of pain experiences
What large structure is contained in the forebrain?
Cerebrum
What is wrapped around the forebrain?
Cerebral cortex
What are the four lobes of the cerebrum?
- Frontal
- Parietal
- Temporal
- Occipital
Which lobe contains the primary motor projection area?
Frontal
What is the prefrontal cortex crucial for?
Planning behaviours and executive functioning
The parietal lobe lies between which two other lobes?
Frontal and occipital
Which lobe contains the primary sensory projection area?
Parietal
Which lobe contains circuits crucial for the control of attention?
Parietal
What is subcortically included in temporal lobes?
The limbic system (includes the amygdala and hippocampus)
Which lobe contains the primary auditory projection area and Wernicke’s area?
Temporal
Which lobe contains the primary visual projection area?
Occipital
What are subcortical structures?
Identified structures of the brain underneath the cortex
Is the thalamus located in the forebrain, midbrain, or hindbrain?
Lower potion of the forebrain
What is the primary role of the thalamus?
To act as a relay station for all nearby sensory information going to the cortex
Where is the hypothalamus located?
Directly below the thalamus in the forebrain
What is the primary role of the hypothalamus?
To control behaviours serving as biological needs/ motivated behaviours (ex. eating, drinking, sex)
What five things is the limbic system involved in?
Emotion, behaviour, motivation, learning, and memory
What are the two main structures of the limbic system?
Amygdala and hippocampus
What is the primary role of the amygdala?
Emotional control and stimulus evaluation
What is the primary role of the hippocampus?
The creation of long-term and spatial memory
What is the primary role of the basal ganglia?
Regulating habitual behaviours
What are the three distinct regions the cerebral cortex is traditionally divided into?
- Motor areas
- Sensory areas
- Association areas
What are convolutions?
The wrinkles visible in the cerebral cortex that allow it to fit into the skull
What is the longitudinal fissure?
- The deepest groove in the cortex
- Divides the left and right central hemispheres
What does the lateral fissure divide?
The frontal lobes on each side of the brain from the temporal lobes
what does the central fissure divide?
The frontal lobes on each side of the brain from the parietal lobes
What is the primary motor projection area?
The departure point for nerve cells that send their signals to genrate a motor output
Do areas with great precision of movement have more or less cortical area devoted to them?
More
T or F: Each region within the primary motor projection area controls the movement of a specific body part.
True
What are the three primary sensory projection areas?
- Primary somatosensory projection area
- Primary auditory projection area
- Primary visual projection area
What will happen if the primary somatosensory projection area is stimulated?
The patient will report a tingling sensation is the associated body part
What will happen if the primary auditory projection area is stimulated?
The patient will hear clicks, buzzes, and hums
What will happen if the primary visual projection area is stimulated?
The patient will see flashes of light or visual patterns
What is the first cortical receiving area of sensory input?
The primary sensory area
Are adjacent areas of visual space represented by adjacent brain sites?
Typically, yes
What is included in the association cortex?
Any portions of the cortex outside the motor and sensory projection areas
What are apraxias?
Disruptions in the initiation or organization of voluntary action
Lesions in areas of which lobe typically cause apraxias?
Frontal
What are agnosias?
Disruption in the ability to identify familiar objects
Lesions in areas of which two lobes typically cause agnosias?
Occipital or the rearmost part of parietal
What is unilateral neglect syndrome?
Patients seem to ignore half of the visual world
Lesions in areas of which lobe typically cause unilateral neglect syndrome?
Parietal
What are aphasias?
Disruptions in language capacities
Lesions in the groove between which two brain areas typically causes aphasia?
The frontal and temporal lobes
Which brain areas are lateralized?
Virtually all of them
What makes integration between cerebral hemispheres possible?
Commissures
What are commissures?
Thick bundles of white matter that transmit information between hemispheres
What is the largest commissure?
Corpus callosum
What is the corpus callosum?
The main commissure linking the two hemispheres
What is a split brain patient?
Patient whose corpus callosum is severed, so there is no communication between hemispheres
Language processing is ______ hemisphere dominant.
Left
Spatial processing is _______ hemisphere dominant.
Right
What is contralateral control?
Pattern in which the left half of the brain controls the right half of the body and vice versa
T or F: Visual projection areas are not contralateral with regard to physical space.
False
What are three things glial cells are responsible for?
- Repair of damaged neural connections
- Guiding the initial development of neural connections
- Provide electrical insulation for some neurons
T or F: Some research suggests that glia may constitute their own signalling system in the brain, separate from information flow provided by neurons.
True
How is electrical insulation provided by glia beneficial for transmission of neuronal signals?
It makes signal transmission faster
What are neurons?
Nerve cells that send messages throughout the body
What are the three main components of a neuron?
- The cell body
- Dendrites
- Axon
What part of the neuron contains the nucleus and metabolic machinery needed to sustain the cell?
The cell body
Which region of the neuron detects incoming signals?
Dendrites
Which region of the neuron sends neural impulses to other neurons?
Axon terminals
What is the myelin sheath?
Layer of tissue surrounding the axon formed by specialized glial cells
What does the myelin sheath do?
Insulates the axon and allows for faster signal transmission
Why does the myelin sheath make signal transmission faster?
- Because of myelin sheath, ions can only flow in or out of axon at gaps between myelin cells
- Makes the signal travelling down the axon have to jump from gap to gap, overall increasing speed
What three things are included in the synapse?
- The presynaptic membrane of one neuron
- The post synaptic membrane of another neuron
- The tiny gap between those neurons
What is the presynaptic membrane?
The cell membrane of the neuron “sending” information across the synapse
What is the postsynaptic membrane?
The cell membrane of the neuron “receiving” the information across the synapse
T or F: The strength of a synaptic connection cannot be altered by experience
False
What are neurotransmitters?
Chemicals released by neurons to stimulate adjacent neurons
When are neurotransmitters released?
When a neuron is sufficiently stimulated
What is a neuron threshold?
The activity/stimulation to which a postsynaptic cell responds by producing an action potential
What is an action potential?
The brief change in the electrical potential of an axon
Does an excitatory post-synaptic potential make the cell more or less likely to achieve action potential?
More likely
Does an inhibitory post-synaptic potential make the cell more or less likely to achieve action potential?
Less likely
What is the all or none law?
A principle stating that a neuron either fires completely or doesn’t fire at all
What causes the graded response of a neuron?
The frequency or length of time a neuron fires
What is coding?
The way in which activity in neurons manages to represent particular ideas or thoughts
What are the two proposals for how neurons code?
- A specific group of neurons represents a specific thought
- Specific thoughts are represented by a distinct broad pattern of neuronal activity (pattern coding)
What type of coding is involved in planning and executing particular motions?
Pattern coding
What are the three proposals about the relationship between the mind and the brain?
- Dualism
- Reductionism
- Dual-aspect theory
What does dualism propose about the relationship between the mind and the brain?
That they have no, or a very limited, relationship
What does reductionism propose about the relationship between the mind and the brain?
That all aspects of the mind can be explained by (or reduced to) biological constructs of the brain
What does the dual-aspect theory propose about the relationship between the mind and the brain?
That the mind and brain are real and separate entities and both deserve to be studied
T or F: Even simple processing in the brain involves multiple regions.
True
