Human neuropsychology Exam 1

Trephination

A surgical procedure that involves removing a circular piece of bone from the skull. Many people say this was done to release demons however looking at the number of holes and the placement this idea is not supported

Egpytians early records of man shuffling foot after brain injury shows early evidence of what?

A knowledge of ipsilateral vs. contralateral brain injuries as well as contra-coup vs coup brain injuries

Ipsilateral

a particular area or function is located in the same hemisphere of the brain as the affected body part. 

Contralateral

A particular area or function is located in the opposite hemisphere of the brain as the affected body part. 

Contra-coup

a type of traumatic brain injury (TBI) that occurs when the brain strikes both the initial impact site (coup) and the opposite side of the skull (contrecoup) due to the force of the impact. 

Hemorrhagic stroke

occurs when a blood vessel in or around the brain ruptures, causing bleeding into the brain tissue. 

Ischemic stroke

occurs when a blood clot blocks an artery in the brain, cutting off blood flow and oxygen to the affected area. 

Medieval cell doctrine

A model of brain function that lasted over 1000 years, located cognitive faculties—like sensing, thinking, and memory—in the fluid-filled cavities of the brain, known as cerebral ventricles

Poseidonus

Believed that the three cells identified by the medieval cell doctrine (the ventricles) has unique functions, the anterior cell was for imagination, the posterior cell was for memory and the middle cell was for reasoning

Mind-Body dualism

Proposed by Rene Descartes, says that there is a split between the mind and the body

Thomas Willis

Identified the circle of willis, saw the emergence of functional systems in the brain

The circle of willis

a ring-like structure of arteries at the base of the brain that connects the anterior and posterior blood supply, it connects the internal carotid arteries and the vertebrobasilar system through anterior and posterior communicating arteries.

Franz Gall

The creator of phrenology, began to localize functions to different areas of the brain

Phrenology

a 19th-century pseudoscience that claimed to understand a person's mental faculties and character by analyzing the "bumps" and contours of the skull

Broca’s aphasia

an expressive language disorder that results from damage to the Broca's area in the frontal lobe, causing difficulty speaking, writing, and forming grammatically complex sentences. Patients are unable to speak but can understand what other are saying.

Broca’s area

the left inferior frontal gyrus, located on the motor strip, meaning damage can result in paralysis

Wernicke’s aphasia

a language disorder caused by damage to the Wernicke's area of the brain, leading to severe difficulty in understanding spoken and written language. Patients can speak but make no sense and are unable to understand others

Wernicke’s area

a region of the brain located in the posterior portion of the left temporal lobe, close to the occipital lobe meaning damage can result in comprehension problems.

Hemiplegia

Paralysis of one side of the body.

Hemiparesis

muscle weakness on one side of the body, affecting the arm, leg, hand, or face, often due to a stroke, brain injury, or tumor

Equipotentiality

Intact cortical areas will pick up the functions of the damaged areas

Karl Lashley

Created the 3 principles:

1. Mass action principle

2. Equipoteniality principle

3. Vicarious principle

Mass action principle

Brain functions as whole, entire brain involved in all activities, relation between dysfunction and extent of damage.

Equipotentiallity principle

All brain cells have potential to carry out any of the functions.

Vicarious functions principle

If one area damaged the other areas will pick it up.

Alexander Luria

Created the three principle functional units

1. Regulation of muscle tone (brain stem)

2. Reception, analysis, and storage (Auditory and visual reception areas)

3. Programming, regulation, and verification (Frontal lobes)

Functional systems

No single area exclusively associated with any given behavior

Tuber’s principle of double dissociation

Declares the conditions for knowing what brain areas are involved with what functions.

1. Destruction of an area causes a specific behavioral deficit

2. Destruction of other areas does not cause that behavioral deficit

Hebb’s law

Neurons that fire together wire together

Dorsal/superior

The top/outer area of the brain

Rostral/anterior

The front area of the brain

Caudal/posterior

The back of the brain, curves down to the lowest part of the brain stem

Ventral/inferior

The bottom/inner area of the brain

Humans neuraxis is…

Bent :(

Medial

Towards the middle

Lateral 

Towards the side

Proximal

Close to the middle

Distal

Away from the middle

What view is this?

Coronal view

What view is this?

Sagittal

What view is this?

Horizontal

Meninges

Tissues that protect the brain by holding it in place, has three layers:

1. Dura mater

2. Arachnoid mater

3. Pia mater

Normal pressure hydrocephalus

a condition where excess cerebrospinal fluid (CSF) accumulates in the brain's ventricles, causing enlargement of these spaces without an increase in intracranial pressure

The 4 symptoms of normal pressure hydrocephalus

1. Walking and posture problems

2. Cognitive problems

3. Urinary incontinence

4. Use of spinal tap

Evan’s index

Used for normal pressure hydrocephalus, measure of proportion of ventriculomegaly to cortical atrophy

Ex vacuo ventriculomegaly

a condition where the ventricles (fluid-filled spaces) in the brain appear enlarged on imaging studies, but there is no increase in cerebrospinal fluid (CSF) pressure. Happens due to atrophy

Internal carotids

Enters the skull and makes a sharp curve, branches and forms anterior cerebral and middle cerebral artery. 

Supplies blood to the anterior 2/3 of the brain, most of the 4 lobes, and the basal ganglia and thalamus

Watershed regions

Where overlap exists between ACA, MCA, and PCA

Vertebrobasilar

The two arteries join at lower edge of pons and form the basilar artery, forms the two posterior cerebral arteries.

Supplies blood to the posterior midline

Anterior cerebral artery syndromes

» Contralateral hemiplegia (no strength, no movement).

» Hemiparesis (reduced strength, weak) on lower limbs.

» Left ACA expressive aphasia (highly unlikely).

» Right ACA expressive aprosodia (highly unlikely).

» Personality changes with orbitofrontal.

Middle cerebral artery syndromes

» May affect most of an entire hemisphere.

» Contralesional hemiplegia.

» Contralesional hemianesthesia.

» Expressive and receptive aphasia.

» Expressive and receptive aprosodia.

» Homonymous hemianopia or quadrantanopia.

» Apraxia.

» Neglect (right).

» Anosognosia (right).

» Gerstmann’s Syndrome: finger agnosia, L/R

confusion, acalculia, agraphia.

Posterior cerebral artery syndromes

» Visual deficits.

» Color perception.

» Prosopagnosia.

» Simultanagnosia.

» Alexia without agraphia with involvement of

posterior forceps of corpus callosum.

» Thalamic syndrome.

» Amnesia with mesial temporal involvement

Gerstmann’s syndrome

A rare neurological disorder characterized by the presence of four symptoms: acalculia (difficulty with math), agraphia (difficulty with writing), finger agnosia (inability to identify one's own fingers), and left-right disorientation. It typically results from a lesion in the dominant parietal lobe, often in the angular gyrus.

Reticular activating system

A network of neurons in the brainstem that acts as a filter for sensory information, controlling your sleep-wake cycle, consciousness, and attention.

Medulla

Contains myelinated tracts for sensory and motor information, nuclei for regulation of vital functions

How many cranial nerves are there?

13

Olfactory nerve (CN I)

Responsible for sense of smell. 

Optic nerve (CN II)

Transmits visual information. 

Oculomotor nerve (CN III)

Controls eye movements, pupil dilation, and eyelid elevation. 

Trochlear nerve (CN IV)

Innervates a single eye muscle responsible for downward and outward eye movements. 

Trigeminal nerve (CN V)

Provides sensation to the face and controls facial muscles. 

Abducens nerve (CN VI)

Controls lateral eye movements. 

Facial nerve (CN VII)

Innervates facial muscles and taste buds on the anterior two-thirds of the tongue. 

Vestibulocochlear nerve (CN VIII)

Responsible for hearing and balance. 

Glossopharyngeal nerve (CN IX)

Carries taste sensation from the posterior one-third of the tongue, controls swallowing, and innervates the salivary glands. 

Vagus nerve (CN X)

Controls heart rate, digestion, and other involuntary functions

Accessory nerve (CN XI)

Controls neck muscles, important for movement of shoulders, neck, and head

Hypoglossal nerve (CN XII) 

Controls tongue muscles

Nervus terminalis (XIII)

Most rostral of all cranial nerves, associated with stimulation of secretion of the hormone gonadotropin

Superior colliculi

Involved in visual reflexes, receive projections from the retina

Inferior colliculi

Receive projections from the ears

Lateral Geniculate body

Projects to visual cortex

Medial geniculate body

Projects to auditory cortex

The four lobes

1. Frontal

2. Parietal

3. Temporal

4. Occipital

Neocortex

Gray matter that covers the brain

Gyri

Ridges

Sulci

Grooves

Sylvian fissure

The deepest sulcus on the lateral surface of the brain, separating the temporal lobe from the frontal and parietal lobes.

Central sulcus

A prominent groove on the lateral surface of the brain that divides the frontal lobe from the parietal lobe. It is a key landmark in neuroanatomy, separating the primary motor cortex (precentral gyrus) from the primary somatosensory cortex (postcentral gyrus)

Superior temporal sulcus

A groove or furrow on the surface of the temporal lobe in the brain. It runs parallel to the sylvian fissure and plays a role in auditory sense

Supramarginal gyrus

a part of the parietal lobe of the brain, located on the lateral surface of the hemisphere, it is U shaped and sits above the sylvian fissure

Precentral sulcus

A prominent groove on the frontal lobe of the brain, located just anterior (in front of) the central sulcus. It serves as the anatomical boundary for the precentral gyrus which is the primary motor cortex

Fusiform gyrus

A structure in the brain located on the base of the temporal and occipital lobes, primarily known for its role in face perception, object recognition, and reading

Postcentral gyrus

A ridge of brain tissue located in the parietal lobe, behind the central sulcus, it is the primary somatosensory cortex, responsible for processing and interpreting sensory information from the body

Opercula

Portions of the frontal, parietal, and temporal lobes that fold over and cover the underlying insular cortex, forming a "little lid" over the Sylvian fissure

Genu of internal capsule

Controlling muscles of face and neck, facial musculature, masticulation, swallowing

Genu in frontal lobe

Collection of fibers in frontal lobe

Splenium 

Collection of fiber in occipital lobe

Insular cortex

A region of the brain located deep within the lateral sulcus (the groove between the frontal and parietal lobes) in each hemisphere

Functional areas

the four cerebral lobes (frontal, parietal, temporal, and occipital), the cerebellum, and the brainstem, each responsible for specific tasks like movement, sensory processing, memory, balance, and vital automatic functions.

Functional areas of the cortex

1. Motor area: precentral gyrus

2. Somatosensory: Postcentral gyrus

3. Visual area: Occipital lobe

4. Auditory: Superior temporal gyrus

5. Gustatory: Insular cortex

Cortical areas

Luria divided the brain behind the central sulcus into three types of regions

1. Primary

2. Secondary

3. Tertiary

Primary cortical zone

High modal specificity, respond to senses, contain cells that respond to specific sense modality. SENSATION

Secondary cortical zone

Adjacent to the primary zone, information is integrated into meaningful wholes. PERCEPTION

Tertiary cortical zone

Lies at the border of the parietal, temporal, and occipital secondary zones. Integrates information but no modality

Hommunculus

A diagrammatic representation of the human body that shows the relative proportions of the brain cortex dedicated to processing sensory or motor functions for different body parts. VARIABLE!!!!

Area 3,1,2 ?

Somatosensory

White matter fibers

1. Projection

2. Commissural

3. Association

Projection fibers

Carry information from deeper structures to the cortex or vice versa

Commissural fibers

Intercerebral, connect homologous areas (Areas of the brain that are similar in function, can be on opposite sides)