Brain Structure and Nervous System

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

Somatic

Controls voluntary movement (skeletal) Receives sensory information Sends motor messages for voluntary innervation of skeletal muscles and glands

Parasympathetic

rest or digest Collectively, does rest and digest Calms body functions down; slowly return to normal functioning Maintain and conserve energy

Autonomic

Controls involuntary responses (organs and glands) Sends involuntary motor messages to the internal organs and glands of the body Two divisions: Sympathetic + Parasympathetic

Frontal Lobe

Broca's Area - Primary Motor Cortex

Motor neurons

CNS to muscles and glands

Two types of nervous system

Central (CNS) and Peripheral (PNS)

Spinal cord

Conducts signals to and from the brain and controls reflex activities.

Central Nervous System (CNS)

Consists of the brain and spinal cord and is responsible for integrating, processing, and coordinating sensory data and motor commands.

Four Lobes

Frontal, Temporal, Parietal and Occipital

Peripheral Nervous System (PNS)

Includes all the neural tissue outside the CNS.

Wernicke's Area

Linked to Broca's area Carl Wernicke (1874) Hypothesised that there was a link between this region and reflexive mimicking of words and meanings Receptive aphasia Wernicke's aphasia Unable to understand language-written or spoken Speech seems nonsense Lack of meaning region of the brain that contains motor neurons involved in the comprehension of speech. This area was first described in 1874 by German neurologist Carl Wernicke. The Wernicke area is located in the posterior third of the upper temporal convolution of the left hemisphere of the brain. Thus, it lies close to the auditory cortex. This area appears to be uniquely important for the comprehension of speech sounds and is considered to be the receptive language, or language comprehension, centre. Damage to the temporal lobe may result in a language disorder known as Wernicke aphasia. An individual with Wernicke aphasia has difficulty understanding language; speech is typically fluent but is empty of content and characterized by circumlocutions, a high incidence of vague words like "thing," and sometimes neologisms and senseless "word salad."

Temporal Lobe Function

Memory (especially new and emotional) Auditory perception -Hearing -Speech production -Memory Language recognition

Parietal Lobe

Primary Sensory Cortex

Occipital Lobe

Primary Visual Cortex

Parietal Lobe Function

Process and integrate sensory information touch, temperature, pain contralateral Spatial awareness and navigation Language processing Read, write and solve mathematical problems Damage: -loss of imagery -spatial issues -left lobe - issues with mathematics

Brain

Receives and processes sensory information, initiates responses, stores memories and generates thoughts and emotions.

Sensory neurons

Sensory organs to CNS

Receptors

Sensory structures that detect changes in the internal or external environment.

Effectors

Target organs whose activities change in response to neural commands.

Motor division

The motor division of the PNS carries motor commands from the CNS to peripheral tissues and systems.

Primary motor cortex

The role of the primary motor cortex is to generate neural impulses that control the execution of movement. At the primary motor cortex, motor representation is orderly arranged (in an inverted fashion) from the toe (at the top of the cerebral hemisphere) to mouth (at the bottom) along a fold in the cortex called the central sulcus. However, some body parts may be controlled by partially overlapping regions of cortex. Each cerebral hemisphere of the primary motor cortex only contains a motor representation of the opposite (contralateral) side of the body. The amount of primary motor cortex devoted to a body part is not proportional to the absolute size of the body surface, but, instead, to the relative density of cutaneous motor receptors on said body part. The density of cutaneous motor receptors on the body part is generally indicative of the necessary degree of precision of movement required at that body part. For this reason, the human hands and face have a much larger representation than the legs. There is a broadly somatotopic representation of the different body parts in the primary motor cortex in an arrangement called a motor homunculus (Latin: little person). These areas are not proportional to their size in the body with the lips, face parts, and hands represented by particularly large areas. Following amputation or paralysis, motor areas can shift to adopt new parts of the body.

Sensory Division

The sensory division of the PNS brings information to the CNS from receptors in peripheral tissues and receptors.

Frontal Lobe Function

Thinking, decision making, feeling and behaviour Social behaviours and regulations Non-task based memories Posterior aspect of the frontal lobe Plan and control the execution of movement Contralateral Left hemisphere controls right side of the body

Broca's Area

Usually found in the left hemisphere Production of speech Named after Paul Broca (1861) Studied brains of dead individuals who lost speechImpairment of Broca's Area Stuttering - underactive Broca's area Expressive Aphasia -know what they want to say but can't say it Broca's area or the Broca area /broʊˈkɑː/ or /ˈbroʊkə/ is a region in the frontal lobe of the left hemisphere (the dominant hemisphere) of the hominid brain with functions linked to speech production. Language processing has been linked to Broca's area since Pierre Paul Broca reported impairments in two patients. Damage to a discrete part of a the brain in the left frontal lobe (Broca's area) of the language-dominant hemisphere has been shown to significantly affect use of spontaneous speech and motor speech control. Broca's area is usually formed by the pars triangularis and the pars opercularis of the inferior frontal gyrus (Brodmann areas 44 and 45). It follows Wernicke's area, and as such they both are usually located in the left hemisphere of the brain. Broca's area is involved mostly in the production of speech. egion of the brain that contains motor neurons involved in the control of speech. This area, located in the frontal part of the left hemisphere of the brain, was discovered in 1861 by French surgeon Paul Broca, who found that it serves a vital role in the generation of articulate speech.Damage to the frontal lobe can result in a speech disorder known as Broca aphasia, which is characterized by deliberate, telegraphic speech with very simple grammatical structure, though the speaker may be quite clear as to what he or she wishes to say and may communicate successfully. The Broca area lies specifically in the third frontal convolution, just anterior to the face area of the motor cortex and just above the Sylvian fissure. It is made up of two areas: the pars triangularis (Brodmann area 45) and the pars opercularis (Brodmann area 44). The Broca area is connected to other regions of the brain, including the Wernicke area, by a neuronal tract known as the arcuate fasciculus. In addition to serving a role in speech production, the Broca area also is involved in language comprehension, in motor activities associated with hand movements, and in sensorimotor learning and integration.

Occipital Lobe Function

Vision -Perception -Colour Damage: -Visual problems -total blindness -blindsight -Cannot consciously see but can respond to objects -motion blindness -hallucinations

Temporal Lobe

Wernicke's Area - Primary Auditory Cortex

Aphasia

acquired language dysfunction with significant impact on life

Sympathetic

fight or flight The 'Flight and Fight' division Known as the stress response Generally, arouses bodily functions Helps you to deal with emergencies and stress Associated with anxiety

Information processing

includes the integration and distribution of information of the CNS

visceral sensory receptors

monitor internal organs

Somatic sensory receptors

provide position, touch, pain and temperature sensations.

Special sensory receptors

provide sensations of smell, taste, vision, balance and hearing.

Homunculus man

sections of cortex in brain designated to each body part latin for little man looks like a grotesque man in diagrams primary motor cortex (frontal lobe)


Ensembles d'études connexes

Chapter: 44 Written Communication and Mail

View Set

4.01 workshop: independent, dependent, and noun clauses

View Set

Extensor muscles in the hand/wrist

View Set

International Business - CHAPTER 2

View Set