Neurobio Final 2

Front 1

structures involved in speech production

Back 1

-Broca’s area is a part of premotor cortex in humans.

-It is responsible for movements important for speech.

--Patients with lesions understand language perfectly well, but they only speak haltingly and agrammatically.

-- In the following passage, a Broca's aphasic patient is trying to explain how he came to the hospital for dental surgery: “Yes... ah... Monday... er... Dad and Peter H... (his own name), and Dad.... er... hospital... and ah... Wednesday... Wednesday, nine o'clock... and oh... Thursday... ten o'clock, ah doctors... two... an' doctors... and er... teeth... yah.”

Front 2

structures involved in memory

Back 2

Hippocampus: Brain area involved in the formation and retrieval of episodic memory (memory of autobiographical events)

Front 3

What happens if there is too much basal ganglia activity?

Back 3

Huntington’s disease: MSNs that project to the GPe degenerate.

Front 4

How would Huntington’s disease affect movement?

Back 4

-The striatal neurons in indirect pathway are lost.

-As a result, the inhibition of neurons in the external palladium is reduced, causing excessive discharge of these neurons.

-The rigidity and akinesia in advanced Huntington’s disease are associated with the loss of the striatal neurons that project to the internal pallidal segment.

Front 5

Symptoms of Huntington’s disease

Back 5

Jerky, random, uncontrollable movements

-Progresses until there is trouble chewing, speaking, and swallowing

-Later, neurons in other parts of the brain degenerate as well, leading to gradual cognitive decline and dementia.

Front 6

Thalamus and emotion

Back 6

-The hypothalamus is an important structure that innervates the reticular formation.

-It integrates information from the body and the rest of the brain to control emotional responses.

-It is particularly important in anger.

Front 7

Prosopagnasia

Back 7

-Prosopagnosia: Inability to recognize faces.

--Including, sometimes, the patient’s own face.

-Patients can recognize that they are faces, and they can derive other information from the face such as the age and sex of the person, but they cannot identify a person from a face.

--Patients are usually able to function in daily life using other cues to identify people.

-Caused by lesions in a specific part of the temporal lobe.

Front 8

hemineglect

Back 8

-Hemineglect is the inability to attend to objects or one’s own body in a portion of space.

--This happens even though visual acuity, somatic sensation, and motor ability are fine.

-Usually accompanied by apraxia on that side: inability to do complex motor actions.

-Some patients:

--Will not eat food from one side of a plate.

--Get lost in familiar places because they will not make left-hand turns or choose doors on the left.

--Only shave or do their makeup on one side of their face.

- Patients act as though the left sides of objects do not exist.

Front 9

Hemineglect is not a visual deficit

Back 9

-Patient was asked to draw lines from each of the dots in this figure:

--Only marked the dots on the right sides.However, the patient could tell the doctor what the entire shape wasIe, “E” or “H” or “circle”.

- Lesions that cause hemineglect

--People with lesions in the right hemisphere in the region of parietal lobe near the occipital lobe all have a very similar pattern of deficits:

-Hemineglect is usually of the left side

--Hemineglect is usually associated with a lesion in the right hemisphere, causing neglect of the left side.

--The left parietal lobe seems to only pay attention to the right side of the world, but the right parietal lobe pays attention to the whole world:

Front 10

balint’s sign

Back 10

-Bilateral lesions of large parts of the parietal lobe causes Balint’s sign:

--Inability to perceive the visual field as a whole (simultanagnosia)- act as if they only see one object at a time.

-- Difficulty in fixating the eyes (ocular apraxia)

-- Inability to move the hand to a specific object by using vision (optic ataxia).

-Balint’s sign combines spatial and attentional deficits.

--Spatial: Ocular apraxia and optic ataxia

--Attentional: Simultanagnosia

Front 11

Facial paresis

Back 11

-Emotion is also associated with muscle movements, particularly of the facial muscles.

-Not wholly controlled by motor cortex.

--Patients with M1 lesions (voluntary facial paresis) can still make emotional expressions.

--Patients with emotional facial paresis can make conscious facial movements but not emotional expressions.

Front 12

depression

Back 12

Depression is associated with abnormal blood flow patterns in the prefrontal cortex, amygdala, and thalamus.

Front 13

Basal Ganglia

Back 13

-The basal ganglia are a large and diverse set of nuclei:

-Caudate, putamen, and the globus pallidus

--The substantia nigra and the subthalamic nucleus (in the ventral thalamus) are also associated with the basal ganglia.

Front 14

D1 and D2 pathway

Back 14

The nigrostriatal projection

-Direct pathway striatal neurons have D1 dopamine receptors, which depolarize the cell in response to dopamine.

-In contrast, indirect pathway striatal neurons have D2 dopamine receptors, which hyperpolarize the cell in response to dopamine.

- Dopaminergic inputs:

--Excite neurons expressing D1 dopamine receptors, which are the ones that project to the GPi.

--Inhibit neurons expressing D2 dopamine receptors, which are the ones that project to the GPe.

Front 15

Nucleus accumbens

Back 15

The basal ganglia in reward

-The important part of the striatum for reward is the ventral and anterior part, called the nucleus accumbens.

-It receives dopaminergic inputs from the ventral tegmental area (VTA).

-Nucleus accumbens neurons project to the ventral pallidum.

Front 16

Dorsal and Ventral Streams of Vision

Back 16

-Dorsal stream: analysis of motion and spatial relationships between objects.

-Ventral stream: recognition and identification of objects.

Front 17

Dorsal Stream & Ventral stream

Back 17

-Dorsal: the "Where Pathway" or "How Pathway"

-Is associated with motion, representation of object locations, and control of the eyes and arms,

- Ventral: the "What Pathway",

- is associated with form recognition and object representation. It is also associated with storage of long-term memory.

Front 18

Parietal Association Cortex

Back 18

-Includes the “dorsal” stream of vision that is concerned with vision for spatial relationships and movement.

-Many areas are concerned with attention.

Front 19

Temporal Lobe

Back 19

-Includes auditory cortex.

-Medial temporal lobe, close to and connected to the hippocampus, seems to be concerned with memory formation.

-Many areas, particularly the inferior temporal lobe, form the “ventral stream” of the visual system, concerned with object identification and classification.