Learning and attention

By now you have a sense of the interwoven roles of dopamine, norepinephrine, and acetylcholine in the control of movement, reward, mood, arousal, and learning and attention. By considering how various drugs manipulate these neurotransmitter systems within the brain, scientists have discovered some consistent patterns that allow us to make predictions about what to expect when specific types of drugs are taken. The same holds true for the neurotransmitter system mentioned several times in this chapter serotonin. What are the consequences of its manipulation in the brain Read on. 

Bushnell PJ, Rice DC. 1999. Behavioral assessments of learning and attention in rats exposed perinatally to 3,3, 4,4, 5-pentachlorobiphenyl (PCB 126). Neurotoxicol Teratol 21(4) 381-392. 

Follow-up children (variable) Children with initial nonencephalopathic clinical Pb poisoning One or more sequelae found as sensory perception and motor coordination impairments, reduced learning and attention span Chisolm (1962, 1968), Kline (1960), Cohen and Ahrens (1959)... 

Many students have difficulty solving chemistry problems, but problem solving is a skill that you can learn and master. To help you, we devote extra attention to setting up and solving problems. Throughout this book, the Examples include information about methods for finding solutions. 

There are three distinct areas of the periodic table—the main group elements, the transition group elements, and the inner transition group elements. We will focus our attention at first on the main group elements, whose properties are easiest to learn and to understand. 

Attention Deficit Hyperactivity Disorder (ADHD) A learning and behavioural disorder characterised by reduced attention span and hyperactivity. ADHD is a diagnosis applied to young children and is typically treated with the amphetamine derivative methylphenidate (Ritalin). 

Cognitive effects Animais Cognitive effects of nicotine have been observed in several species, including humans. Experimental studies have focused primarily on the effects on attention and memory. Cognitive benefits are seen after both acute and chronic administration (Levin et al. 1992). In experimental animals, nicotine improves learning and memory on a variety of tasks. Conversely, the nicotinic antagonist mecamylamine... 

This pretty much sums up the key features of the nervous system of humans and identifies some of the key molecules involved one way or another with its functions. In the next chapter, I turn attention largely to diseases of the nervous system but conclude with a vignette about the mechanisms for learning and memory. 

In this chapter, 1 tnm hrst to a few additional examples of central nervous system diseases. I begin with two examples that have a clear genetic basis and move on to others for which there is clear genetic disposition bnt an nnclear genetic basis. Later, I will provide some examples—good and bad—of the actions of small molecules on the nervous system. Finally, 1 tnm attention to the issnes of learning and memory. 

Some of these compounds are currently undergoing pharmacological studies on models of attention, learning and memory, as well as extensive preclinical evaluation [77]. 

Figure la. Ascending activation from subcortical nuclei (see Fig. 2a) generates a stable platform of consciousness, essential for normal cognitive functions such as selective attention, learning and memory, and higher executive functions (Walker Ballard, 1998). 

The peptide, melatonin, has been implicated in autism. Excess melatonin is thought to decrease learning, memory, attention, emotionality, motivation and pain responses (reviewed Chamberlain Herman, 1990)—all behaviours that are abnormal in autism. Melatonin, released from the pineal gland, is implicated in controlling serotonin and POMC (proopiomelanocortin) peptides, such as beta-endorphin, and an elevation may contribute to, or cause, the serotonin and opioid abnormalities (Chamberlain Herman, 1990). 

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