Neurology Exam 1

Neuroplasticity

The brain’s ability to reorganize

Upper motor neuron cell body locations

Cerebral cortex, brainstem or cerebellum

Frontal Lobe function

Controlling Voluntary Movement and Thinking/ Problem Solving

Parietal Lobe function

Perception and processing of sensation

Occipital Lobe function

Visual Perception

Temporal Lobe function

Contains portions of the limbic system (emotion, memory), auditory system, olfactory system, area for recognizing faces

Limbic System function

Responsible for memory and emotion

Insula

Involved in awareness of sensation and emotion

Basal Ganglia

Involved in generating movement, thought and emotions

Brainstem

Basic life functions (such as breathing and heart rate)

Gray matter composition

Neuron cell bodies and dendrites

White matter composition

Myelinated axons

Hemorrhagic stroke

Artery rupture (brain bleed)

Ischemic stroke

Occluded artery

Blood brain barrier

Controls passage of substances from the blood to the fluid that surrounds the neurons

Ventricles

Contain cerebrospinal fluid (CSF)

Neurons

Generate and transmit information to control body functions and allow for thought, emotions and memories

Glial Cells

Surround and support the neurons

Dendritic spines

Where nerve cells receive input from other neurons

Astrocytes

Form blood-brain barrier

Oligodendroglial cells

Form the myelin sheath that insulates axons in the brain and spinal cord

Microglia

Act like phagocytes to remove and degrade damaged cells

Ependymal Cells

Line ventricles of the brain and central canal of the spinal cord. Produce CSF

Schwann Cells

Surround and protect the peripheral nerve fibers, form myelin sheath, assist in regeneration by forming guiding tunnels for regrowth

Association axons

Connect with different parts of the brain in the same hemisphere

Commissural axons

Run between hemispheres (ex: corpus collosum)

Projection fibers

Connect cortex with different parts of the CNS (ex: internal capsule)

Primary Motor Cortex location

Precentral gyrus

Primary Motor Cortex lesion effect

Paralysis on the contralateral side of the body and muscles of facial expression on the bottom portion of the face

Premotor Cortex location

Just anterior to primary motor cortex

Premotor Cortex function

Control action of trunk and limb muscles

Premotor Cortex lesion

Unilateral neglect

Supplementary Motor Area location

Medial to the premotor cortex

Supplementary Motor Area function

Stores motor memories, directs activity of the primary motor cortex

Supplementary Motor Area lesion

Apraxia, motor planning deficit

Broca’s Area location

For most people located in the left hemisphere only. (Left-handed people may have a right Broca’s area)

Broca’s Area function

Contains motor programs for speech and language

Non-dominant hemisphere of Broca’s area function

Controls nonverbal communication

Ataxia

Uncoordinated movement that manifests when voluntary movements are attempted

Apraxia

An impairment of voluntary learned movement that is characterized by an inability to perform purposeful movements

Orbitofrontal Cortex function

Impulse control, inhibition of inappropriate behaviors and carrying out plans

Orbitofrontal Cortex lesion

Can’t make realistic plans, or carry out plans. Trouble with focus, organization and inhibition of impulses (prefrontal syndrome)

Ventromedial Frontal Cortex function

Connects emotions with thought, attaches emotional meaning to life experiences

Ventromedial Frontal Cortex lesion

Flat emotional affect

Anterior Cingulate Gyrus function

Integrates thought, motivation, attention and behavior

Somatosensory Cortex location

Postcentral gyrus

Somatosensory Cortex function

Perceives sensations such as pain, temperature, pressure, touch, vibration and proprioception

Somatosensory Association Area function

Interpretation of somatosensory information

Somatosensory Association Area dysfunction

Body image disorders, such as anorexia nervosa and unilateral neglect

Parietotemporal Association Cortex function

Abstract thought, reasoning, reading and writing, mathematics and spatial perception

Angular Gyrus function

Understanding written language

Primary Visual Cortex function

Visual perception

Primary Visual Cortex lesion

Loss of vision in the opposite visual field ( hemianopsia

Visual Association Cortex function

Interpreting visual stimuli

Visual Association Cortex location

Anterior to primary visual cortex

Visual Association Cortex lesion

Can see objects or faces, but not recognize (visual agnosia)

Primary Auditory Cortex function

Sound perception

Auditory Association Cortex location

Posterior to the primary auditory cortex

Auditory Association Cortex function

Interpretation and understanding of sounds

Wernicke’s Area location

Usually located only on left side

Wernicke’s Area function

Understanding language

Wernicke’s Area lesion

Receptive aphasia

Inferotemporal Lobe function

Recognition of faces, objects, colors

Inferotemporal Lobe lesion

Inability to recognize faces of people they know (Prosopagnosia)

Olfactory Cortex function

Perceiving odor

Olfactory Cortex location

The medial part of the temporal lobe

Olfactory Cortex lesion

Loss of sense of smell (anosmia)

Amygdala location

Medial side of temporal lobe

Amygdala function

Involved in strong negative emotion

Hippocampus location

Medial side of temporal lobe

Hippocampus function

Creation of new long-term memories

Hippocampus lesion

Inability to create new long-term memories and have anterograde amnesia

Diencephalon components

Thalamus, Hypothalamus, Epithalamus, Subthalamus

Thalamus function

Relay station of incoming motor and sensory information

Association Nuclei function

Receives action potentials from CNS and sends projections to limbic regions of the cortex where they connect sensory input to emotional response

Intralaminar Nuclei function

Maintaining conscious awareness

Intralaminar Nuclei lesion

Coma

Reticular Nucleus of Thalamus function

Determines which signals will be conveyed to the cerebral cortex and controls the relay nuclei

Reticular Nucleus of Thalamus dysfunction

Linked to disorders such as Autism in which the ability to modulate sensory input is limited

Thalamic (Pain) Syndrome cause

Compromise of blood supply from the posterior cerebral artery

Thalamic (Pain) Syndrome symptoms

Hemianesthesia, sensory ataxia (motor incoordination due to loss of proprioceptive information from muscles, joints and tendons) and thalamic pain

Thalamic pain

Intense and unpleasant. Is often not treated effectively with pain medications. Caused by abnormal pain modulation when the thalamus is damaged

Hypothalamus function

Controls the autonomic nervous system

Vasopression

Controls water balance; causes constriction of blood vessels -> increase BP

Oxytocin

Causes constriction of smooth muscles in uterus and mammary gland

Central Autonomic Fibers

Neurons that descend directly from hypothalamus to the brainstem and spinal cord in the reticulospinal tracts

Epithalamus function

Secretes melatonin