Study Guide for Neuroplasticity

1.4a The Brain: Neuroplasticity and Tools of Discovery

1.4-1 Why are psychologists concerned with human biology?

Biological Psychology - the scientific study of links between biological (genetic, neural, hormonal) and psychological processes. Some biological psychologists call themselves behavioral neuroscientists, neuropsychologists, behavior geneticists, physiological psychologists, or bio psychologists. 

Levels of Analysis - the differing complimentary views, from biological to psychological to social-cultural, for analyzing any given phenomenon. 

1.4-2 The Power of Neuroplasticity

How do biology and experience together enable neuroplasticity?

Neuroplasticity also called Brain plasticity - refers to the brain's ability to change (especially during childhood) and adapt as a result of experience. Neuro refers to neurons, the nerve cells that are the building blocks of the brain and nervous system, and plasticity refers to the brain's malleability.

1.4-3 Tools of Discovery: Having our Head Examined

Lesion - tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue.

EEG - An electroencephalogram is a test used to evaluate the electrical activity in the brain. Brain cells communicate with each other through electrical impulses. An EEG can be used to help detect potential problems associated with this activity. An EEG tracks and records brain wave patterns. Non-invasive.

CAT scan (Computerized Axial Tomography) a sophisticated x-ray of the brain. It gives us a 3D picture of the brain which is great for locating tumors, but it does NOT show brain activity or function.

MRI (Magnetic Resonance Imaging) - a method used for studying the functions of the brain (or any living tissue) without surgery. For example, with a MRI, a psychologist can observe different structures in the brain by having a subject perform certain exercises or tasks.

MRI scan of a healthy individual (left) and a person with schizophrenia (right). Note the enlarged ventricle, the fluid filled brain region at the tip of the arrow in the  image on the right.

PET (Positron Emission Tomography) - Produces visual display of brain activity.  Computer translates signals into map of brain at work enables researchers to see what areas of brain are most active during certain tasks different scans used for different chemicals such as neurotransmitters, drugs, & oxygen flow

!MRI Functional Magnetic Resonance Imaging - Combines elements of MRI and PET scans. shows details of brain structure with info about blood flow in the brain, linking brain structure with brain activity during cognitive tasks.

Common Types of Neural Measures

Phineas Gage - large iron rod was driven through his head destroying much of his left frontal lobe. Known for injury's effect on personality and judgement. (Some skeptical of claim)

1.4b The Brain: Brain Regions and Structures

1.4-4 What are the hindbrain, midbrain and forebrain?

Hindbrain

The hindbrain consists of the structures in the top part of the spinal cord. The hindbrain is our life support system; it controls the basic biological functions that keep us alive. Some of the important specific structures within the hindbrain are the medulla (regulates heart rate and breathing), pons (connects the hindbrain with the midbrain and forebrain. Also involved in the control of facial expressions) and the cerebellum.

• Cerebellum - the part of the brain at the back of the skull, rear of the brainstem. Its functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory.  in vertebrates. Known as little brain.

Hanging at the back of the brain, the cerebellum coordinates our voluntary movements, as when soccer star Cristiano Ronaldo controls the ball.

Midbrain

For purposes of the AP exam, you should know that this area is between the hindbrain and the forebrain and integrates some types of sensory information and muscle movements.  Contains the Reticular Formation.

1.4-5 The Brainstem

Brain stem- keeps you alive and contains the reticular activating system (RAS), which regulates arousal level, the medulla, which regulates heart rate and breathing, and the thalamus, which connects the sensory apparatus and the higher brain. The thalamus directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla. Connects all the portions of the brain.

Forebrain

Areas of the forebrain control what we think of as thought and reason. Contains the thalamus, hypothalamus, amygdala, hippocampus and the cerebral cortex.

1.4-6 The Limbic System

Limbic system- the emotional brain. It contains the hypothalamus, which regulates basic drives (hunger, thirst, sex), the amygdala, which regulates the primitive emotions of anger and fear, and the hippocampus, which is important for short-term memory.   FYI- long-term memory is not localized but it stored throughout the cerebral cortex.  

Amygdala - two lima bean sized neural clusters in the limbic system; linked to emotion.

The Hypothalamus - a limbic system neural structure lying below (hypo) the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system, and is linked to emotion and reward.

Hippocampus - a neural center in the limbic system that helps process explicit (conscious) memories of facts and events for storage.

1.4-7 The Cerebral Cortex

Cerebral Cortex - This is the upper, complex brain, which is larger in humans than other animals. The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information processing centers. It is divided into four parts called lobes, which are divided by fissures:

• Frontal lobe- responsible for complex associations among other brain parts, involved in speaking and muscle movements and making plans and judgement; motor strip is also located here.

• Parietal lobe- holds the sensory cortex (incoming messages to the brain).

• Occipital lobe- where vision is processed, and internal visualizations occur

• Temporal lobe- includes the auditory areas, each receiving information from the opposite ear. responsible for speech and language in Wernicke’s (comprehension of speech) and Broca’s area (production of speech).

Motor Cortex – also found in the frontal lobe. Responsible for outgoing messages from the brain. Controls voluntary movements.

Somatosensory Cortex - an area at the front of the parietal lobes that registers and processes body touch and movement sensations.

Association Areas - areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are  involved in higher mental functions such as learning, remembering, thinking and speaking. 

 Other key brain part:

• Corpus Callosum – the broad band of nerve fibers that connects the two hemispheres of the brain.

1.4c The Brain: Damage Response and Brain Hemispheres

1.4-8 Responses to Damage

Neuroplasticity also called Brain plasticity - refers to the brain's ability to change (especially during childhood) and adapt as a result of experience. Neuro refers to neurons, the nerve cells that are the building blocks of the brain and nervous system, and plasticity refers to the brain's malleability.

Neurogenesis - the formation of new neurons.

1.4-9 The Divided Brain

Corpus Callosum – the broad band of nerve fibers that connects the two hemispheres of the brain.

The brain is divided left to right between hemispheres by the corpus callosum, which allows messages to pass between the two sides. The left side is the sadder, verbal, logical, and reasoning side. The right side is the happier, intuitive, spatial, and artistic side. FYI- long-term memory is not localized but it stored throughout the cerebral cortex.    

Split brain - a condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers  (mainly those of the corpus callosum)  connecting them.

Right-left differences in the Intact Brain - when a person performs a perceptual task, a brain scan often reveals increased activity in the right hemisphere. When the person speaks or does a math calculation, activity increases in the left hemisphere.

Although the left hemisphere is skilled at making quick, literal interpretations of language, the right hemisphere:

• Excels in making inferences

• Helps us modulate our speech

• Helps us orchestrate our self-awareness