PSYC31H3 Week 3 Notes on Chapter 4
Traumatic Brain Injury/ Head Injury:
• One of the most common and severe difficulties for an individual to experience is a
traumatic brain injury (TBI). The peak ages for TBI are in the 15-24 year range. People
older than 64 years and children, younger than the age of 5 are the next groups most at
risk for TBI. Males sustain TBI at a far greater rate than females except in the older-than-
64 age range and children younger than age 5.
• TBI can result from a myriad of causes and the actual TBI tends to be classified as either
an open or a closed head injury.
• The severity of a TBI, whether caused by an open or closed head injury is usually
measured by a combination of the following factors:
(a) Length of posttraumatic amnesia (PTA), the period between receiving a head
injury and regaining continuous day-to-day memory for events.
(b) Depth of unconsciousness usually measured immediately after resuscitation
using the Glasgow Coma Scale (GCS).
(c) Length of unconsciousness and/or presence of neurological signs.
The GCS measures depth of coma through determining the individual’s
responsiveness level in eye opening, motor movement, and verbal
communication. Scores on the GCS range from 3-15, with higher scores
indicating more intact functioning. Scores 3-8 are classified as having a severe
TBI and those scores of 9-12 having moderate TBI.
Open Head Injury:
• Open Head Injury: A brain injury which occurs when an object penetrates the skull and
exposes the brain to the elements.
• The most common cause is a gunshot wound, but any object sharp enough to pierce the
skull and expose the cortex may cause an open head injury. In addition, the force behind
an object can make many nonlethal objects potentially lethal (pens, pencils, keys or any
• The amount of damage in an open head injury is related to the amount of energy exerted
on the brain. An object that penetrates the brain and fragments causing internal ricochet
or debris to be driven durther into the brain is likely to cause more brain involvement.
Clean wounds cause less damage than those with more brain involvement. A clean
wound implies that the damage is mainly along the path of the invading object.
Secondary effects of open head injuries may include hypotension (low blood pressure),
hypovolemia (low blood volume), contusions, and intracranial hematomas. • Neuropsychological difficulties with open head injuries include specific cognitive deficits
and behavioural changes related to the site of the lesion. In addition, patients tend to
show the effects of general diffuse brain impairment, such as difficulties with
concentration, attention, memory, and overall mental slowing.
• Prevention and treatment of infection I also crucial because the brain has been exposed
to the elements. Open head injury is highly related to epilepsy, with estimates of 80% of
patients experiencing seizures within the first 24 hours.
Closed Head Injury:
• Closed Head Injury: Impact from an accident or injury causes brain damage but does not
penetrate the skull.
• Coup: The initial impact in a traumatic brain injury as an object or event impinges on the
skull covering the brain.
• Contrecoup: Secondary impact in a traumatic brain injury as the brain ricochets back
and forth or side to side within the skull.
• Stronger force applied to the brain has the potential for greater damage. Primary
difficulties include diffuse white matter damage, contusion (bruising), and hemorrhage.
Diffuse axonal injury is caused by the acceleration and deceleration of the brain
impacting against the skull. Contusions often occur under the frontal and temporal poles
where the shearing forces of the brain are impacting on the sharpest and most confined
parts of the skull. Contusions can also occur under the point of impact or at the
contrecoup. Hemorrhages occur when blood vessels supplying oxygen to the brain are
• Secondary damage includes injuries resulting from hematomas, cerebral hemorrhage,
infection hydrocephalus, and anoxic damage caused by breathing difficulties or low
blood pressure. All of these difficulties may begin at the initial time of injury and lead to
secondary damage to the brain. In addition, there may be neurochemical difficulties such
as changes in neuropeptides, electrolytes, and excitatory amino acids.
• The most common causal factors are moving vehicle accidents, including automobiles,
motorcycles, boats, and all-terrain vehicles (ATVs) as the source. Another major source
of closed head injury is participating in athletics and, more specifically, in sports that do
not require protective headwear such as professional boxing or soccer.
• Neuropsychological difficulties for individuals with closed head injury are similar to those
with open head injury except they may be less severe. Typical symptoms include
impaired speed of information processing, difficulties with concentration and attention,
memory deficits, and problems with reaction time.
• Closed head injury patients often experience behavioural and/or personality changes
subsequent to the injuries. In addition, most closed head injury patients experience
some form of depression or other emotional difficulty usually because of changes in their life circumstances. Another difficulty is posttraumatic stress disorder (PTSD) if the closed
head injury was caused by a trauma.
• Treatment for closed head injuries is similar to open head injury in terms of the medical
needs being prominent. Very important is the need to prevent or control brain swelling.
Next, because of the myriad of psychosocial difficulties, it is often helpful to enlist the aid
of a therapist or support group. Psychoactive medications may also be necessary for
some individuals. Antidepressants have been used to alleviate the depression which
may often occur secondary to closed heard injury. A typical antipsychotics and
anticonvulsants have been used to help with anger management and behavioural
• Postconcussion syndrome: Constellation of physical and psychological symptoms that
may occur as a result of a medically verifiable concussion.
• This involves the traits and behaviours that exist after an individual has received a TBI
caused by a concussion. Not currently listed in the DSM-IV-TR as a disorder, it is
considered a syndrome under study and will probably be included in DSM-V along with
mild neurocognitive disorder.
• A concussion is primarily caused by diffuse axonal injury, where axons are damaged or
destroyed because of the forces of acceleration and deceleration acting on them and on
• Symptoms of concussion include loss of consciousness, PTA, and sometimes seizures.
In the spectrum of TBI, a concussion is considered mild compared to open or closed
• Neuropsychological deficits in postconcussion syndrome include attention deficits,
impaired verbal retrieval, and forgetfulness. Other symptoms reported by patients
include headaches, dizziness, irritability, sleep disturbances, and fatigue.
• Other researchers suggest that the residual symptoms seen in mild TBI exist due to the
significant stress the individual was under at the time of the TBI.
• Finally, genetic studies also have identified the E4 allele of ApoE thought to relate to the
risk for Alzheimer’s disease as a contributor to the severity of damage of TBI. The
supposition is that identification of E4 allele in the patient may point to a more sever
• Patients are typically given pain relievers such as nonsteroidal analgesics for headaches
and medications to relieve depression, nausea, or dizziness. Rest is advised but is only
• There have been numerous instances where individuals, particularly young people and
athletes, have chosen not to seek medical help and have tried to return directly to their daily lives. At times, the results of returning too early to one’s activities involve
unexpected failures or inability to perform as one could before the concussion.
• Studies have shown that alcohol, especially wine, in moderation has protective effects
from cardiovascular and cerebrovascular disease. Drinking in moderation or social
drinking is usually defined as one or two drinks in a day.
• Alcohol, however, when not used in moderation may cause moderate to severe
difficulties for the central nervous system. There are many varied definitions and
descriptions of alcohol abuse and dependence usually based on the frequency and
chronicity of drinking.
• Alcohol abuse, as described in the DSM-IV-TR, is defined as the excess use of alcohol
for a period of 12 months. During this time, the use of alcohol has been shown to have a
negative impact on the individual’s social or occupational functioning.
• Alcohol dependence is defined in the DSM-IV-TR as the same pattern with the inclusion
of tolerance and/or withdrawal.
Tolerance: Usually associated with alcohol consumption but can relate to other
drugs; the need for more and more of substance to achieve the same level of
intoxication or “high”.
Withdrawal: Symptoms that occur after the cessation of us of substance; each
drug has its own symptoms of withdrawal.
• Binge Drinking: The drinking of an excessive amount of alcohol within a short period
often with the intent of becoming quickly intoxicated.
However, drinking large quantities of alcohol within a short period of toxic. The
body is not able to metabolize the substance when it is consumed so quickly, and
there have been accounts of alcohol poisoning sometimes leading to coma and
What little information that does exist suggests that binge drinkers appear to be
less prone to alcohol-related cognitive deficits than those with a heavy daily
• Drug Abuse Resistance Education (DARE): A program developed to assist children and
adolescents to respond against peer pressure to consume alcohol or other drugs.
• Alcohol is a central nervous system depressant and as such depresses or slows the
functioning of structures within the central nervous system. Alcohol has a paradoxical
effect in that it often procedures a feeling of euphoria before the onset of depressive
feelings. Researchers often find that this paradox is one reason some individuals
develop difficulties with alcohol. The positive feeling or euphoria does not continue as
one continues to drink but the individual who is drinking may demonstrate poor judgement associated with intoxication and conclude that more will make him feel even
better, whereas in reality it leads to depression.
• Alcohol is a neurotoxin and as such could be considered a poison. Alcohol is
metabolized differently than other drugs in a process termed zero-order kinetics. It is
metabolized at a ready state, approximately one drink per hour regardless of the amount
consumed by the person. It is metabolized through several different routes, which
explains its effects on multiple central nervous system areas, as well as on multiple
• Chronic alcohol use may cause multiple cognitive deficits including difficulties with
complex visuospatial abilities and psychomotor speed. Memory deficits, once thought to
be hallmark of chronic alcohol users, can be severe but are not evident in all alcohol
abuser. However, as the memory task increases in complexity there is more of a chance
• Severe difficulties related to alcohol use include alcohol use include alcoholic dementia
and Korsakoff’s syndrome. Alcohol dementia involves widespread cognitive deterioration
similar to other forms of dementia. The dementia is progressive and involves cognitive
and memory abilities along with abstract reasoning. An individual with dementia caused
by alcohol use should recover some abilities with abstinence.
• Korsakoff’s syndrome: is characterized by difficulty with short-term memory and other
memory deficits. The person may appear to have manic confusion and be unable to
clearly state his thoughts. The person also exhibits disoriented eye and limb movements.
The cause of these symptoms is significant alcohol intake over a period with subsequent
vitamin deficiency. Alcohol interferes with gastrointestinal absorption of the vitamin
thiamine. Thiamine deficiency is associated with cognitive and emotional changes.
• It has been shown that this syndrome can be treated if thiamine if given as soon as
possible and alcohol use is curtailed.
• Cannabis or marijuana is the herbal form and hashish is the resinous form of the plant
Cannabis Sativa. The biologically active compound in marijuana is tetrahydrocannabinol
(THC). It has psychoactive and physiological effects which vary based on whether the
substance is smoked, sniffed, or ingested.
• Marijuana’s effects have been described as pleasant and/or unpleasant often related to
variables similar to alcohol, specifically the mental state of the user at the time of use
and the expectations of the user in terms of the effects of the drug.
• Marijuana has the potential to induce hallucinatory experiences and emotional states-
some good, some bad- as well as time distortions and memory loss. The intensity of
these effects is dose dependant. High doses may result in psychotic-like symptoms.
Even lesser doses may result in psychotic symptoms in those individuals who have a
predisposition or vulnerability to schizophrenia. • Cannabis is known to act on the hippocampus, an organ associated with memory and
learning and impact short-term memory and attention. Some studies show personality
changes with heavy usage. The most common symptoms include emotional blunting,
mental sluggishness, apathy, restlessness, mental confusion, and an amotivational
• As can be seen, there are two sides to the question regarding the effects of marijuana.
One side states that there are various cognitive, memory, and emotional effects because
of the use of the drug, whereas the other side states these effects do not exist or are not
as serious as reported.
• The most significant and consistent finding is that marijuana has a deleterious effect on
reaction time and has been implicated in many traffic accidents.
• Considered a central nervous system stimulant, cocaine is highly addictive due to the
“rush” which is experienced through inhalation. The effect is much less when the drug is
taken intravenously. Other effects of cocaine include increased alertness and arousal
and an increased sense of well-being and confidence, which is often interpreted as
positive and may lead to continual use.
• Cocaine increases the level of dopamine in the reward circuits in the brain, which leads
to craving and a higher threshold for euphoric reaction to the drug. Beginning use of
cocaine may function as an aphrodisiac but with prolonged use lowers libido and may
cause impotence. Other reactions to cocaine include paranoia, delusions, and
hallucinations and panic attacks. Beginning use of cocaine acts as a pleasure inducer
but with repeated use, it damages the brains reward centers.
• Long-term users of cocaine may have many cognitive deficits with memory and
concentration difficulties the most significant. Seizures occur with many habitual as well
as new users. Hypertension and other symptoms of central nervous system
overstimulation such as strokes may occur. Indicate that fMRI imagery shows abnormal
metabolism and hyperfusion both when subjects are using cocaine and in chronic users
when abstinent. The neuroimaging findings are consistent with findings of slowed mental
processing, memory muscle movement have been observed.
• Current information indicates withdrawal from cocaine is neither life threatening nor
terribly painful. However, symptoms of irritability, restlessness, confusion, sleep disorder,
and abnormal muscle movements have been observed.
• Cocaine-addicted individuals made more errors on the Erikson flanker task, cognitive
task, and were less likely to correct errors than were a control group. The researchers
argued that the results were associated with the compromised dopamine system.
Narcotics • The first opiate drugs were derived from the opium poppy. Heroin, morphine, and
codeine are all forms of synthetic derivation. Opiates have been used by many cultures
for centuries to ease pain and produce euphoria.
• Frederick Serturner discovered the synthetic version of opium, which he termed
• Two acetyl groups were attached to the morphine molecule to produce heroin and it was
placed on the market in 1898 by Bayer Laboratories.
• The Harrison Narcotics Tax Act which was more of a taxation law than a way to control
the spread of the substance was passed in 1914. Pharmacists and physicians who dealt
with narcotics were required to register and pay tax. Narcotics now were only available
by prescription. However, this only changed the way that individuals wanting narcotics
were able to obtain them and contributed to the increase in cost.
• The opiates compete with the naturally occurring endorphins for the receptor sites. The
major medicinal use for narcotics is pain control.
• Narcotics also have effects on the gastrointestinal system through the ability to
counteract diarrhea and were another use or narcotics has been in the control of the
cough control center in the medulla through the introduction into cough medicine.
• Tolerance develops for all of the narcotics and is often a problem for individuals who use
the drugs appropriately for pain control. Cross-tolerance also develops; therefore, if an
individual is tolerant for one narcotic he or she will be tolerant to all.
• Narcotics cause physical dependence, which means they cause withdrawal symptoms,
withdrawal is often described as a bad case of the flu or worse. Narcotics also cause
• In addition, the use of needles and other paraphernalia involved with the preparation of
narcotics may cause the person to feel pleasure at the sight of his or her equipment.
Also present when needles are used is the risk of HIV infection or hepatitis.
• Excess opiate use may lead to decreased response and decreased memory storage.
Death may result because of the ability of narcotics to depress the respiratory center of
the brain. Long-term use of opiates may lead to visuospatial and visuomotor difficulties.
Mental and physical neglect are often symptoms specific to the heroin use. Pau, Lee and
Chan found that heroin addicts, in comparison to control subjects, exhibited difficulties
with impulse control whereas, attention and mental flexibility in abstinent recovering
addicts were not affected. Long-term users of opiates who remain abstinent may recover
many lost abilities.
• Methamphetamine (meth) is currently the most visible drug available. It is visible in the
sense that it is readily available, is cheap compared to other drugs, and the target of the
media and law enforcement. The drug is easy to make at home. The ingredients and directions are available on the internet. It causes such a high that “normal” individuals
are willing to risk their jobs, families and friends for the next hit of meth. Meth’s effects
have been described as similar to several simultaneous orgasms. When taken to
excess, meth can give the appearance of psychosis.
• When its medicinal use was replaced by new medications which were not physically
addictive. The new medications which interest the market were methylphenidate (Ritalin)