Biological Bases of Behavior Unit 1 AP Psych (Nervous System & Hindbrain)

Central Nervous System (CNS)

The brain and spinal cord

Peripheral nervous system

Sensory and motor neurons that connect the CNS to the rest of the body

What is the PNS divided into?

• Somatic Nervous System

• Autonomic Nervous System

Somatic Nervous system

Controls voluntary muscle movement

• motor cortex

The somatic nervous system uses?

Uses motor neurons

• The neurons that carry outgoing information from the CNS to the muscles and glands

Autonomic Nervous System

• Part of the peripheral nervous system that controls the glands and muscles of the internal organs

• Controls the automatic functions of the body

What categories is the autonomic nervous system divided into?

• Sympathetic

• Parasympathetic

Sympathetic nervous system

Division of ANS that arouses the body, mobilizing its energy in stressful situations

What does the sympathetic nervous system do?

Automatically accelerates heart rate, breathing, dilates pupils, slows down digestion

Parasympathetic nervous system

• Division of the autonomic nervous system that calms the body, conserving its energy

• Automatically slows the body down after a stressful event

What does the parasympathetic nervous system do?

Heart rate and breathing slow down, pupils constrict and digestion speeds up

The nervous system

The brain

Made up of neurons (which are made throughout lifetime) and glial cells

Glial cells

Structural support for neural cells

Cerebrospinal fluid

Provides nourishment & cushion for brain

Ways of studying the brain

• Accidents

• Lesions

• Electroencephalogram (EEG)

• Computerized axial tomography (CAT/CT scan)

• Magnetic resonance imaging (MRI)

• Positron emission tomography (PET) scan

• Functional MRI (fMRI)

Accidents

Think Phineas Gage

Lesions

The removal or destruction of part of the brain

Electroencephalogram (EEG)

Detects brain waves

Computerized axial tomography (CAT/CT scan)

Uses x-rays to produce a three dimensional picture of the brain

Magnetic resonance imaging

Uses magnetic fields to create a more detailed image than a CAT scan

Positron Emission Tomography (PET) Scan

Lets research see what areas of the brain are most active during certain tasks

Functional MRI (fMRI)

Can tie brain structure to brain activity during cognitive tasks

What are the 3 parts of the brain?

• Hindbrain

• Midbrain

• Forebrain

Brainstem includes?

• Midbrain

• Pons

• Medulla Oblongata

Brainstem

Involved in the autonomic control of salivation, respiration, heartbeat, digestion

Hindbrain

• Medulla oblongata

• Pons

• Cerebellum

Where is the medulla oblongata located?

Located at the base of the brainstem

What does the medulla oblongata do?

Involved in heart rate, breathing, & BP

Pons

• Connects hindbrain, midbrain and forebrain, together

• Involved in facial expressions

• Effects REM

Where is the cerebellum located?

Located in the back of our head “little brain”

What is the cerebellum responsible for?

Responsible for muscle control including balance and movement

Midbrain

Coordinates simple movements with sensory information

Midbrain

• Reticular activating system

Reticular activating system

Involved in arousal, alertness, and sleep-wake cycles

Forebrain

• Thalamus

• Limbic System

• Hippocampus

• Amygdala

• Hypothalamus

Thalamus

• Receives sensory information and sends them to appropriate areas of forebrain

  • Then transmits replies to cerebellum and medulla

• Everything but smell!

Limbic System

Neural structures at border of brainstem and cerebral hemispheres (doughnut-shaped)

The limbic system is?

The emotional control center of the brain

What is the limbic system made up of?

• Hypothalamus

• Amygdala

• Hippocampus

Hippocampus

Involved in memory processing

Amygdala

Vital for our basic emotions

Hypothalamus

• Controls:

  • Body temp

  • Hunger

  • Thirst

  • Sexual Arousal (libido)

  • The endocrine system

Endocrine System

The body’s “slow” chemical communication system

What does the endocrine system include?

• Pituitary gland

• Adrenal gland

• Ovaries & testes

Hormones

Chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues.

Adrenaline

• Secreted in large amounts when an individual is stimulated by fear, anxiety, or a similar stress-related reaction

  • Released mainly thru the activation of nerves connected to the adrenal glands

Leptin

• Manufactured & secreted by fat cells

• Leptin receptors have been found in the hypothalamus

• Food intake is reduced when the receptors are stimulated

Ghrelin

• Secreted by endocrine cells in the stomach

• Binds to growth hormone receptors in the hypothalamus and pituitary gland

• Stimulates appetite and the release of growth hormone.

Melatonin

• Produced by the pineal gland

• Implicated in the initiation of sleep and in the regulation of the sleep wake cycle

Oxytocin

• Produced in the hypothalamus

• Facilitates social affiliation

• Promotes good feelings such as trust and bonding