PSYCH 240 Lecture Notes - Lecture 3: Basal Ganglia, Cerebral Cortex, Spatial Visualization Ability
Psych Lecture 3 Reading Notes
Cognitive psychologists are especially concerned with how the anatomy and the physiology
of the nervous system affect and are affected by human cognition
Cognitive Neuroscience: studies how the brain and other aspects of the nervous system are
linked to cognitive processing and, ultimately, to behavior
The brain is the organ in our bodies that most directly controls our thoughts, emotions, and
motivations; the brain is reactive and directive
A major focus of brain research is localization of function (referring to the specific areas of
the brain that control specific skills or behaviors)
The nervous system is the basis for our ability to perceive, adapt to, and interact with the
world around us
Cerebral cortex: the part of the brain that controls many of our thought processes
The brain has three major regions: forebrain, midbrain, and hindbrain
Forebrain: the region of the brain located toward the top and front of the brain
Includes the cerebral cortex, the basal ganglia, the limbic system, the thalamus, and the
hypothalamus
Cerebral cortex: the outer layer of the cerebral hemispheres- it plays a vital role in our
thinking and other mental processes
The basal ganglia are collections of neurons crucial to motor function; dysfunction of the
basal ganglia can result in motor deficits
The limbic system is important in emotion, motivation, memory, and learning
Mammals and humans have more developed limbic systems compared to animals
Our limbic system allows us to suppress indistinctive responses and help us adapt our
behaviors flexibly in response to our changing environment
The limbic system comprises of 3 central interconnected cerebral structures: the septum, the
amygdala, and the hippocampus
The septum is involved in anger and fear; the amygdala plays an important role in emotion as
well, especially in anger and aggression
Stimulations of the amygdala commonly results in fear in ways such as palpitations, fearful
hallucinations, or frightening flashbacks in memory
Damage to or removal of the amygdala can result in maladaptive lack of fear
The amygdala also enhances the perception of emotional stimuli
People with autism display limited activation in the amygdala: a theory of autism is that the
disorder involves dysfunction of the amygdala, which leads to the social impairment that is
typical of persons with autism
Two other effects of lesions to the amygdala can be visual agnosia (inability to recognize
objects) and hyper sexuality
The hippocampus is essential in memory formation; it is essential for flexible learning,
seeing relationships among items learned and spatial memory
The hippocampus also appears to keep track of where things are and how these things are
spatially related to each other- it monitors what is wear
People who have suffered damage or the removal of a hippocampus still can recall existing
memories but they cannot form new memories
A disease that produces loss of memory function is Korsakoff’s syndrome
find more resources at oneclass.com
find more resources at oneclass.com
Other symptoms include apathy, paralysis of muscles controlling the eye, and tremor
This loss is believed to be associated with deterioration of the hippocampus and is caused by
a lack of thiamine in the brain; this can result from excessive alcohol use, dietary
deficiencies, or eating disorders
Disruption in the hippocampus appears to result in deficits in declarative memories ( memory
for pieces of information) but not in deficits in procedural (memory for courses of action)
The thalamus relays incoming sensory information through groups of neurons that project to
the appropriate region in the cortex; most of the sensory input into the brain passes through
he thalamus, which is approx. the center of the brain
The thalamus is divided into a number of nuclei; each nucleus receives info from specific
senses; this info is then relayed to corresponding specific areas in the cerebral cortex; the
thalamus also helps in control of sleep and waking
When the thalamus malfunctions the result can be pain, tremor, amnesia, impairment of
language, and disruptions in waking and sleeping
In cases of schizophrenia, imaging and in vivo studies reveal abnormal changes in the
thalamus that result in difficulties in filtering stimuli and focusing attention, which in turn
can explain why people suffering from schizophrenia experience hallucinations and delusions
The hypothalamus regulates behavior related to species survival: fighting, feeding, fleeing,
and mating; it also helps regulate emotions and react to stress; it interacts with the limbic
system; the small size of the hypothalamus belies its importance in controlling many bodily
functions; the hypothalamus plays a role in sleep
Dysfunction and neural loss within the hypothalamus are noted in cases of narcolepsy,
whereby a person falls asleep often and at unpredictable times
The hypothalamus also is important for the functioning of the endocrine system
It is involved in stimulating the pituitary glands, through which a range of hormones are
produced and released; structures in the forebrain, midbrain, and hindbrain perform functions
essential for survival as well as for high-level thinking and feeling
Midbrain: helps to control eye movement and coordination
Reticular Activating System is a network of neurons essential to regulating consciousness,
including sleep; wakefulness; arousal; attention to some extent; and vital functions, such as
heartbeat and breathing
The RAS also extends into the hindbrain; both the RAS and the thalamus are essential to our
conscious awareness of our control over our existence
The hindbrain, along with the thalamus, midbrain, and hypothalamus, make up the brainstem,
which connects the forebrain to the spinal cord
Physicians make a determination of brain death based on the function of the brainstem- if it
has been damages so severely that various reflexes of the head are absent for more than 12
hours, or the brain must show no activity or blood circulation
Hindbrain: comprises the medulla oblongata, the pons, and the cerebellum
The medulla oblongata controls heart activity and largely controls breathing, swallowing, and
digestion; the medulla is also the place at which nerves from the right side of the body cross
over to the left side of the brain and nerves from the left side of the body cross over to the
right side of the brain
The medulla oblongata is an elongated interior structure located at the points at which the
spinal cord enters the skull and joins with the brain
find more resources at oneclass.com
find more resources at oneclass.com
The medulla oblongata, which contains part of the RAS, helps to keep us alive
The pons contains neural fibers that pass signals from one part of the brain to another
The pons also contains a portion of the RAS and nerves serving parts of the head/face
The cerebellum controls bodily coordination, balance, and muscle tone, as well as some
aspects of memory involving procedure-related movements
The prenatal development of the human brain roughly corresponds to the evolutionary
development of the human brain with the species as a whole
The hindbrain is evolutionarily the oldest and most primitive and the first to develop
prenatally; the midbrain is a relatively newer and the next part to develop; the forebrain is the
most recent evolutionary addition and the last to develop
The most important of these evolutionary trends is the increasing neural complexity of the
brain; the evolution of the human brain has offered us the enhanced ability to exercise
voluntary control over behavior; it has also strengthened our ability to plan and to
contemplate alternative courses of action
Cerebral Cortex and Localization of Function:
The cerebral cortex is extremely important in human cognition- it allows us to think, plan,
coordinate thoughts and actions, perceive patterns, and use language
The cerebral cortex forms a 1-3 mm layer that wraps the surface of the brain
In humans, the many convolutions, or creases, of the cerebral cortex include three elements:
Sulci: small grooves; fissures: large grooves; gyri: bulges between sulci and fissures; these
folds greatly increase the surface area
The volume of the human skull has more than doubled over the past 2 million years, allowing
for the expansion of the brain, and especially the cortex
The surface of the cerebral cortex is grayish and is referred to as gray matter because it
includes the grayish neural-cell bodies that process the info that the brain receives and sends;
in contrast, the underlying white matter includes mostly white, myelinated axons
The cerebral cortex forms the outer layer of the two halves of the brain-left and right cerebral
hemispheres- these hemispheres function differently
Right hemisphere receptors in the skin generally send info through the medulla to areas in the
left hemisphere; the receptors on the left side transmit info to the right
The left hemisphere directs motor responses on the right hemisphere and vice versa
Not all info transmission is contralateral from one side to another
Some ipsilateral transmission (on the same side) occurs as well
The corpus callosum is a dense aggregate of neural fibers connecting the 2 cerebral
hemispheres and transmits info back and forth
If the corpus callosum is cut, the two cerebral hemispheres cannot communicate with each
other so even though some things (ex. Language) are highly lateralized, most functioning-
even language- depends on integration of both hemispheres
Hemispheric Specialization: the study of hemispheric specialization in the human brain can be
traced back to Marc Dax who treated more than 40 patients suffering from aphasia-loss of
speech- as a result of brain damage
He noticed that damage to the left hemisphere in his patients led to loss of speech
Paul Broca claimed that an autopsy revealed that an aphasic stroke patient had a lesion in the
left cerebral hemisphere so he was convinced that the left hemisphere of the brain is critical
in speech, a view that has held up over time
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Cognitive psychologists are especially concerned with how the anatomy and the physiology of the nervous system affect and are affected by human cognition. Cognitive neuroscience: studies how the brain and other aspects of the nervous system are linked to cognitive processing and, ultimately, to behavior. The brain is the organ in our bodies that most directly controls our thoughts, emotions, and motivations; the brain is reactive and directive. A major focus of brain research is localization of function (referring to the specific areas of the brain that control specific skills or behaviors) The nervous system is the basis for our ability to perceive, adapt to, and interact with the world around us. Cerebral cortex: the part of the brain that controls many of our thought processes. The brain has three major regions: forebrain, midbrain, and hindbrain. Forebrain: the region of the brain located toward the top and front of the brain.
